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As filed with the Securities and Exchange Commission on March 31, 2026

Registration No. 333-      

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SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM S-4

REGISTRATION STATEMENT
UNDER

THE SECURITIES ACT OF 1933

VYNE THERAPEUTICS INC.

(Exact Name of Registrant as Specified in Its Charter)

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P.O. Box 125

Stewartsville, NJ 08886

(800) 775-7936

(Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant’s Principal Executive Offices)

Mutya Harsch

Chief Legal Officer and General Counsel

VYNE Therapeutics Inc.

P.O. Box 125

Stewartsville, NJ 08886

(800) 775-7936

(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent For Service)

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Copies to:

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Approximate date of commencement of proposed sale of the securities to the public: As soon as practicable after the effective date of this registration statement and the satisfaction or waiver of all other conditions under the Merger Agreement described herein.

If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box ☐

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

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If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

If applicable, place an X in the box to designate the appropriate rule provision relied upon in conducting this transaction: Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer) ☐

Exchange Act Rule 14d-1(d) (Cross-Border Third-Party Tender Offer) ☐

The Registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

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SUBJECT TO COMPLETION, DATED                   , 2026

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PROPOSED MERGER
YOUR VOTE IS VERY IMPORTANT

To the Stockholders of VYNE Therapeutics Inc. and Yarrow Bioscience, Inc.,

VYNE Therapeutics Inc., a Delaware corporation (“VYNE”), and Yarrow Bioscience, Inc., a Delaware corporation (“Yarrow”), entered into an Agreement and Plan of Merger and Reorganization, dated as of December 17, 2025, which was amended on January 30, 2026 (as amended, the “Merger Agreement”), pursuant to which, among other matters, Yellow Merger Sub Corp., a direct, wholly owned subsidiary of VYNE (“Merger Sub”), will merge with and into Yarrow, with Yarrow surviving as a wholly owned subsidiary of VYNE and the surviving corporation of the merger (the “Merger”). VYNE following the Merger is referred to herein as the “Combined Company.”

At the effective time of the Merger (the “Effective Time”), (i) each then-outstanding share of Yarrow common stock, par value $0.0001 per share (the “Yarrow Common Stock”), and Yarrow Series A Preferred Stock, par value $0.0001 per share (the “Yarrow Preferred Stock” and, together with the Yarrow Common Stock, the “Yarrow Capital Stock”) (including any shares of Yarrow Common Stock issued in the Yarrow Pre-Closing Financing described below), excluding any shares of Yarrow Capital Stock held as treasury stock immediately prior to the Effective Time and any dissenting shares, will be converted into the right to receive a number of shares of VYNE common stock, par value $0.0001 per share (the “VYNE Common Stock”) and/or VYNE Pre-Funded Warrants (as defined below) equal to the exchange ratio described in more detail in the section titled “The Merger Agreement — Exchange Ratio” beginning on page 161 of the accompanying proxy statement/prospectus, referred to herein as the “Exchange Ratio,” (ii) each then- outstanding option (a “Yarrow Option”) to purchase shares of Yarrow Common Stock will be converted into and become an option to purchase shares of VYNE Common Stock on the existing terms and conditions (including with respect to vesting and accelerated vesting), subject to adjustment as set forth in the Merger Agreement, and (iii) each then- outstanding and unexercised pre-funded warrant to purchase shares of Yarrow Common Stock (each, a “Yarrow Pre- Funded Warrant”) will be converted into a pre-funded warrant to purchase shares of VYNE Common Stock on the existing terms and conditions (each, a “VYNE Pre-Funded Warrant”), subject to adjustment as set forth in the Merger Agreement and the form of pre-funded warrant. If any shares of Yarrow Common Stock are unvested or subject to a repurchase option or risk of forfeiture at the Effective Time, then the shares of VYNE Common Stock issued in exchange for such shares will to the same extent be unvested and subject to the same repurchase option or risk of forfeiture.

Each share of VYNE Common Stock that is issued and outstanding at the Effective Time will remain issued and outstanding and such shares, subject to the proposed reverse stock split, will be unaffected by the Merger. Prior to the Effective Time, the VYNE board of directors will accelerate the vesting of all options to purchase shares of VYNE Common Stock (“VYNE Options”) and all restricted stock units (“VYNE RSUs”). Each outstanding VYNE Option with an exercise price per share equal to or less than the volume weighted average closing trading price of a share of VYNE Common Stock on The Nasdaq Stock Market LLC (“Nasdaq”) for the five consecutive trading days ending three trading days prior to the Calculation Date (as defined in the Merger Agreement), as reported by Bloomberg L.P. (the “VYNE Closing Price” and such VYNE Options, “In-the-Money VYNE Options”), will be cancelled at the Effective Time and such holder thereof will receive an amount in cash, without interest, less any applicable tax withholding, equal to the product obtained by multiplying the excess of the VYNE Closing Price over the exercise price per share of the VYNE Common Stock underlying such VYNE Option by the number of shares of the VYNE Common Stock underlying such VYNE Option (“VYNE Stock Option Cash Consideration”). Each VYNE Option with an exercise price greater than the VYNE Closing Price (an “Out-of-the-Money VYNE Option”) will be cancelled for no consideration. Immediately prior to the Effective Time, each holder of an accelerated VYNE RSU will be entitled to receive a number of shares of VYNE Common Stock equal to the number of vested and unsettled shares underlying such VYNE RSU.

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Based on VYNE’s and Yarrow’s capitalization as of December 17, 2025 and taking into account VYNE’s current cash position, each share of Yarrow Capital Stock is currently estimated to be entitled to receive approximately 35.8667 shares of VYNE Common Stock. This estimated Exchange Ratio does not give effect to the proposed VYNE reverse stock split and is subject to adjustment based on VYNE’s estimated Net Cash (as defined herein) at the Closing as described in more detail in the section titled “The Merger Agreement — Exchange Ratio” beginning on page 161 of the accompanying proxy statement/prospectus.

In connection with the execution and delivery of the Merger Agreement, certain institutional and accredited investors entered into a stock purchase agreement, pursuant to which such persons invested in a private placement of Yarrow Preferred Stock for an aggregate purchase price of approximately $100 million. Prior to the closing of the Merger (the “Closing”), certain investors entered into a securities purchase agreement (the “Securities Purchase Agreement”), pursuant to which such persons have agreed to purchase shares of Yarrow Common Stock or Yarrow Pre-Funded Warrants for an aggregate purchase price of approximately $100 million (the “Yarrow Pre-Closing Financing”). The closing of the Yarrow Pre-Closing Financing is conditioned upon the satisfaction or waiver of the conditions to the Closing as well as certain other conditions. The Yarrow Pre-Closing Financing is more fully described in the accompanying proxy statement/prospectus.

Immediately after the Merger, VYNE securityholders as of immediately prior to the Merger are expected to own approximately 3.0% of the outstanding shares of the Combined Company on a fully-diluted basis, former Yarrow securityholders, excluding shares purchased in the Yarrow Pre-Closing Financing, are expected to own approximately 61.5% of the outstanding shares of the Combined Company on a fully-diluted basis, and shares of Yarrow Common Stock and Yarrow Pre-Funded Warrants issued in the Yarrow Pre-Closing Financing are expected to represent approximately 35.5% of the outstanding shares of capital stock of the Combined Company on a fully-diluted basis, subject to certain assumptions.

Shares of VYNE Common Stock are currently listed on The Nasdaq Capital Market under the symbol “VYNE.” VYNE has filed an initial listing application for the Combined Company with Nasdaq. After completion of the Merger, VYNE will be renamed “Yarrow Bioscience, Inc.” and it is expected that the Combined Company common stock will trade on Nasdaq under the symbol “YARW.” On       , 2026, the last trading day before the date of the accompanying proxy statement/prospectus, the closing sale price of VYNE Common Stock was $     per share. Under the Merger Agreement, each of VYNE’s and Yarrow’s obligation to complete the Merger is subject to the satisfaction or waiver by each of the parties of various conditions, including that the shares of VYNE Common Stock to be issued in the Merger have been approved for listing (subject to official notice of issuance) on Nasdaq as of the Closing. In the event that the shares of VYNE Common Stock to be issued in the Merger are not approved for listing on Nasdaq, it is possible that VYNE and Yarrow may mutually agree to waive the applicable condition and nonetheless proceed with completion of the Merger. If such condition is waived, VYNE will not recirculate an updated proxy statement/prospectus, nor will it solicit a new vote of stockholders prior to proceeding with the Merger. Accordingly, you are advised that VYNE stockholders will not have certainty regarding the listing of the Combined Company’s shares at the time you are asked to vote at the special meeting described below.

VYNE stockholders are cordially invited to attend the special meeting in lieu of the annual meeting of VYNE stockholders. VYNE is holding its special meeting in lieu of the annual meeting of stockholders (the “VYNE Special Meeting”), on           2026, at         , Eastern Time, unless postponed or adjourned to a later date, in order to obtain the stockholder approvals necessary to complete the Merger and related matters. The VYNE Special Meeting will be held at         . VYNE stockholders will be able to attend and participate in the VYNE Special Meeting in person where they will be able to ask questions and vote. At the VYNE Special Meeting, VYNE will ask its stockholders to:

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As described in the accompanying proxy statement/prospectus, certain VYNE stockholders who in the aggregate beneficially owned approximately 3.0% of the outstanding shares of VYNE Common Stock as of December 17, 2025, and certain Yarrow stockholders who in the aggregate owned approximately 95.9% of the outstanding shares of Yarrow capital stock as of December 17, 2025, are parties to stockholder support agreements with VYNE and Yarrow whereby such stockholders have agreed to vote in favor of the approval of the transactions contemplated therein, including, with respect to such Yarrow stockholders, adoption of the Merger Agreement and approval of the Merger and, with respect to such VYNE stockholders, Proposal Nos. 1 – 2, subject to the terms of the support agreements. Following the effectiveness of the registration statement on Form S-4 of which the accompanying proxy statement/prospectus is a part and pursuant to the Merger Agreement, Yarrow stockholders holding a sufficient number of shares of Yarrow capital stock to adopt the Merger Agreement and approve the Merger and related transactions will be asked to execute written consents providing for such adoption and approval.

Further, prior to the Effective Time, the VYNE board of directors expects to declare and set aside the aggregate cash amount to be paid in accordance with a pre-Closing special cash dividend (the “Cash Dividend”) to holders of record of outstanding shares of VYNE Common Stock and outstanding VYNE warrants (the “VYNE Warrants”) as of a record date prior to the Effective Time, to be set by the VYNE board of directors as close as reasonably practicable to (but not later than) the anticipated Closing. The ex-dividend date in respect of such Cash Dividend will be determined by Nasdaq. VYNE stockholders of record who continue to hold their eligible shares of VYNE Common Stock or VYNE Warrants until market open on the ex-dividend date will be entitled to payment of the Cash Dividend. The Cash Dividend will be equal in the aggregate to VYNE’s reasonable, good faith approximation of the amount by which VYNE’s Net Cash (as determined pursuant to the Merger Agreement) is expected to exceed $0 as of the Closing. The aggregate amount of the Cash Dividend is expected to be approximately $14.5 million to $16.5 million.

After careful consideration, each of the VYNE and Yarrow boards of directors have approved the Merger Agreement and have determined that it is advisable to consummate the Merger. The VYNE board of directors has approved the proposals described in the accompanying proxy statement/prospectus and recommends that its stockholders vote “FOR” the proposals described in the accompanying proxy statement/prospectus.

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More information about VYNE, Yarrow, the Merger Agreement and transactions contemplated thereby and the foregoing proposals is contained in the accompanying proxy statement/prospectus. VYNE urges you to read the accompanying proxy statement/ prospectus carefully and in its entirety. IN PARTICULAR, YOU SHOULD CAREFULLY CONSIDER THE MATTERS DISCUSSED UNDER “RISK FACTORS” BEGINNING ON PAGE 27 OF THE ACCOMPANYING PROXY STATEMENT/ PROSPECTUS.

VYNE and Yarrow are excited about the opportunities the Merger brings to VYNE’s and Yarrow’s stockholders and thank you for your consideration and continued support. Sincerely,

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Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of the accompanying proxy statement/prospectus. Any representation to the contrary is a criminal offense.

The accompanying proxy statement/prospectus is dated         , 2026, and is first being mailed to VYNE’s stockholders on or about         , 2026.

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VYNE THERAPEUTICS INC.

P.O. Box 125

Stewartsville, NJ 08886

(800) 775-7936

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS IN LIEU OF ANNUAL MEETING OF STOCKHOLDERS

To the stockholders of VYNE Therapeutics Inc. (“VYNE”):

NOTICE IS HEREBY GIVEN that a special meeting in lieu of the annual meeting of stockholders (the “VYNE Special Meeting”), will be held on          , 2026, at          , Eastern Time, unless postponed or adjourned to a later date. The VYNE Special Meeting will be held at          . You will be able to attend and participate in the VYNE Special Meeting in person where you will be able to ask questions and vote.

The VYNE Special Meeting will be held for the following purposes:

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Record Date: The VYNE board of directors has fixed          , 2026 as the record date for the determination of stockholders entitled to notice of, and to vote at, the VYNE Special Meeting and any adjournment or postponement thereof. Only holders of record of shares of VYNE Common Stock at the close of business on the record date are entitled to notice of, and to vote at, the VYNE Special Meeting. At the close of business on the record date, VYNE had       shares of common stock outstanding and entitled to vote.

Your vote is important. The affirmative vote of a majority of the votes properly cast for and against by the holders of VYNE Common Stock at the VYNE Special Meeting, assuming a quorum is present, is required for approval of Proposal Nos. 1, 2, 3, 4, 5, 7, 8, 9 and 10. The affirmative vote of a plurality of the votes properly cast by the holders of VYNE Common Stock entitled to vote at the VYNE Special Meeting, assuming a quorum is present, is required for the election of the director nominated via Proposal No. 6. Approval of each of Proposal No. 1 and Proposal No. 2 is a condition to the completion of the Merger. Therefore, the Merger cannot be consummated without the approval of Proposal Nos. 1 and 2. The approval of Proposal Nos. 3, 4, 5 and 8 are not conditions to the completion of the Merger, however, each of these proposals are conditioned on the consummation of the Merger and will not be implemented if the Merger is not consummated. Approval of Proposal Nos. 2, 6, 7, 9 and 10 are requested whether or not the Merger is consummated.

Even if you plan to attend the VYNE Special Meeting, VYNE requests that you sign and return the enclosed proxy or vote by mail or online to ensure that your shares will be represented at the VYNE Special Meeting if you are unable to attend. You may change or revoke your proxy at any time before it is voted at the VYNE Special Meeting.

VYNE’S BOARD OF DIRECTORS HAS DETERMINED AND BELIEVES THAT EACH OF THE PROPOSALS OUTLINED ABOVE IS FAIR TO, IN THE BEST INTERESTS OF, AND ADVISABLE TO VYNE AND ITS STOCKHOLDERS AND HAS APPROVED EACH SUCH PROPOSAL. VYNE’S BOARD OF DIRECTORS RECOMMENDS THAT VYNE STOCKHOLDERS VOTE “FOR” EACH SUCH PROPOSAL.

Important Notice Regarding the Availability of Proxy Materials for the Stockholders’ Meeting to Be Held on          , 2026 at              , Eastern Time at             .

The proxy statement/prospectus and annual report to stockholders in connection with the special meeting in lieu of annual meeting are available at https://materials.proxyvote.com/92941V.

By Order of the VYNE Board of Directors,

David Domzalski

Chief Executive Officer

           , 2026

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EXPLANATORY NOTE

The issuances of (i) all shares of VYNE Common Stock and/or VYNE Pre-Funded Warrants, as applicable, in exchange for each share of Yarrow Capital Stock (including shares of Yarrow Common Stock issued in the Yarrow Pre-Closing Financing), (ii) all shares of VYNE Common Stock issuable upon exercise of VYNE Pre-Funded Warrants issued in exchange for Yarrow Pre-Funded Warrants sold in the Yarrow Pre-Closing Financing and/or existing shares of Yarrow Capital Stock, as applicable, (iii) all VYNE Pre-Funded Warrants in exchange for each Yarrow Pre-Funded Warrant and (iv) all options to purchase shares of VYNE Common Stock issued in exchange for options to purchase shares of Yarrow Common Stock are intended to be covered by this registration statement on Form S-4 of which this proxy statement/prospectus is a part.

There is no difference between (A) the shares of VYNE Common Stock that will be issued in exchange for each share of Yarrow Common Stock issued in the Yarrow Pre-Closing Financing, (B) the shares of VYNE Common Stock that will be issued in exchange for each other share of Yarrow Capital Stock not exchanged for a VYNE Pre-Funded Warrant, (C) the shares of VYNE Common Stock that will be issuable upon the exercise of VYNE Pre-Funded Warrants that will be issued in exchange for Yarrow Pre-Funded Warrants sold in the Yarrow Pre-Closing Financing and/or existing shares of Yarrow Capital stock, as applicable, (D) the VYNE Pre-Funded Warrants that will be issued in exchange for each Yarrow Pre- Funded Warrant and/or existing share of Yarrow Capital Stock and (E) the options to purchase shares of VYNE Common Stock that will be issued in exchange for options to purchase shares of Yarrow Common Stock, as applicable.

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REFERENCES TO ADDITIONAL INFORMATION

This proxy statement/prospectus incorporates important business and financial information about VYNE Therapeutics Inc. that is not included in or delivered with this document. You may obtain this information without charge through the Securities and Exchange Commission website (www.sec.gov) or upon your written or oral request by contacting the Corporate Secretary of VYNE Therapeutics Inc. by calling (800) 775-7936 or via email to mutya.harsch@vynetx.com.

To ensure timely delivery of these documents, any request should be made no later than            , 2026 to receive them before the VYNE Special Meeting.

For additional details about where you can find information about VYNE, please see the section titled “Where You Can Find More Information” beginning on page 347 of this proxy statement/prospectus.

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QUESTIONS AND ANSWERS ABOUT THE MERGER

Except where specifically noted, the following information and all other information contained in this proxy statement/prospectus does not give effect to the proposed reverse stock split described in Proposal No. 2 of this proxy statement/prospectus.

The following section provides answers to frequently asked questions about the Merger. This section, however, provides only summary information. For a more complete response to these questions and for additional information, please refer to the cross-referenced sections.

For a more complete description of the treatment of Yarrow securities in the Merger, please see the sections titled “The Merger Agreement — Merger Consideration,” and “The Merger Agreement — Exchange Ratio” beginning on page 160 of this proxy statement/ prospectus. For a description of the effect of the Yarrow Pre-Closing Financing on Yarrow’s current securityholders, please see the section titled “Agreements Related to the Merger — Securities Purchase Agreement” beginning on page 177 of this proxy statement/prospectus.

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Immediately after the Merger, VYNE securityholders as of immediately prior to the Merger are expected to own approximately 3.0% of the outstanding shares of the Combined Company on a fully- diluted basis, former Yarrow securityholders, excluding shares purchased in the Yarrow Pre-Closing Financing, are expected to own approximately 61.5% of the outstanding shares of the Combined Company on a fully-diluted basis, and shares and pre-funded warrants issued in the Yarrow Pre- Closing Financing are expected to represent approximately 35.5% of the outstanding shares of capital stock of the Combined Company on a fully-diluted basis, subject to certain assumptions, including, but not limited to, VYNE’s Net Cash as of Closing being approximately $0.

In addition, prior to the Effective Time, the VYNE board of directors expects to declare the Cash Dividend to stockholders of record of outstanding shares of VYNE Common Stock and holders of VYNE Warrants as of the record date prior to the Effective Time, to be set by the VYNE board of directors as close as reasonably practicable to (but not later than) the Effective Time. The ex-dividend date in respect of such Cash Dividend will be determined by Nasdaq. VYNE stockholders of record and holders of VYNE Warrants who continue to hold their eligible shares of VYNE Common Stock or VYNE Warrants, respectively, until market open on the ex-dividend date will be entitled to payment of the Cash Dividend. The Cash Dividend will be equal in the aggregate to VYNE’s reasonable, good faith approximation of the amount by which VYNE’s Net Cash (as determined pursuant to the Merger Agreement) is expected to exceed $0. VYNE currently estimates that the aggregate amount of cash to be distributed to stockholders of record as of the record date for the Cash Dividend will be approximately $14.5 million to $16.5 million.

For a more complete description of the treatment of VYNE securities in the Merger, please see the sections titled “The Merger Agreement — Merger Consideration,” “The Merger Agreement — Exchange Ratio,” and “Market Price and Dividend Information” beginning on pages 160, 161 and 26, respectively, of this proxy statement/prospectus.

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as to the available cash that will be left to distribute to stockholders after paying the obligations of VYNE and setting aside funds for reserves.

Immediately after the Merger, the shares of Yarrow Common Stock and Yarrow Pre-Funded Warrants issued in the Yarrow Pre-Closing Financing are expected to represent approximately 35.5% of the outstanding shares of the Combined Company common stock. VYNE, Yarrow and the investors participating in the Yarrow Pre-Closing Financing have also agreed to enter into a registration rights agreement at the closing of the Yarrow Pre-Closing Financing, pursuant to which, among other things, the Combined Company will agree to provide for the registration and resale of certain shares of VYNE Common Stock that are held by the investors participating in the Yarrow Pre-Closing Financing from time to time pursuant to Rule 415. The closing of the Yarrow Pre-Closing Financing is conditioned upon the satisfaction or waiver of the conditions to the Closing as well as certain other conditions. The closing of the Yarrow Pre-Closing Financing is not a condition to the closing of the Merger.

Therefore, VYNE stockholders are being asked to vote on the Merger without assurance that the proceeds of the Yarrow Pre-Closing Financing will be available at the time the Merger is consummated. The investors in the Yarrow Pre-Closing Financing have executed binding purchase agreements and are obligated to fund their respective commitments at closing, and Yarrow would be entitled to pursue specific performance and other contractual remedies to enforce those obligations. However, if the Merger closes before the financing proceeds are received, the Combined Company would initially operate using its then-available cash resources and may need to adjust the timing or scope of certain expenditures until such proceeds are received or alternative capital is obtained.

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For a more complete description of the Yarrow Pre-Closing Financing, please see the sections titled “Agreements Related to the Merger — Securities Purchase Agreement” and “Agreements Related to the Merger — Registration Rights Agreement” beginning on pages 177 and 179 of this proxy statement/ prospectus, respectively.

Q:What proposals will be voted on at the VYNE Special Meeting in connection with the Merger?

Approval of each of Proposal Nos. 1 and 2 is a condition to completion of the Merger. The issuance of VYNE Common Stock in connection with the Merger and the change of control resulting from the Merger will not take place unless Proposal No. 1 is approved by VYNE stockholders and the Merger is consummated. The amendment to the VYNE Charter to effect a reverse stock split of VYNE’s issued and outstanding common stock will not take place unless Proposal No. 2 is approved by the requisite VYNE stockholders but is expected to take place whether or not the Merger is consummated.

In addition to the requirement of obtaining VYNE stockholder approval, the Closing is subject to the satisfaction or waiver of each of the other closing conditions set forth in the Merger Agreement. For a more complete description of the closing conditions under the Merger Agreement, please see the section titled “The Merger Agreement — Conditions to the Completion of the Merger” beginning on page 173 of this proxy statement/prospectus.

The presence, in person or being represented by proxy, at the VYNE Special Meeting of the holders of one-third of the shares of VYNE Common Stock outstanding and entitled to vote at the VYNE Special Meeting is necessary to constitute a quorum at the meeting for the purpose of approving the Merger Proposals.

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The approvals of Proposal Nos. 3, 4, 5, 6, 7, 8, 9 and 10 are not conditions to the completion of the Merger. The implementation of Proposal Nos. 3, 4, 5 and 8 are each conditioned on the consummation of the Merger. VYNE does not expect that any matter other than the Proposals will be brought before the VYNE Special Meeting.

The presence, in person or being represented by proxy, at the VYNE Special Meeting of the holders of at least one-third of the shares of VYNE Common Stock outstanding and entitled to vote at the VYNE Special Meeting is necessary to constitute a quorum at the meeting for the purpose of approving the proposals.

Votes will be counted by the inspector of election appointed for the meeting, who will separately count “FOR” and “AGAINST” votes, abstentions or “WITHHOLD” votes (as applicable), and broker non- votes. Abstentions or “WITHHOLD” votes and broker non-votes will be treated as shares present for the purpose of determining the presence of a quorum for the transaction of business at the VYNE Special Meeting, but will not be counted as votes cast and will have no effect on the outcome of the vote for each proposal.

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common stock) or voting power of an issuer could constitute a change of control. Nasdaq will consider all facts and circumstances concerning a transaction, including whether there are any other relationships or agreements between the company and the investor or group. Nasdaq Listing Rule 5635(d) also requires stockholder approval for a transaction other than a public offering involving the sale, issuance or potential issuance by an issuer of common equity securities (or securities convertible into or exercisable for common equity securities) at a price that is less than market value of the stock if the number of equity securities to be issued is or may be equal to 20% or more of the common equity securities, or 20% or more of the voting power, outstanding before the issuance.

In the case of the Merger, VYNE expects to issue approximately 106.2 million shares of VYNE Common Stock, excluding approximately 1.28 billion shares of VYNE Common Stock underlying the Yarrow Pre-Funded Warrants and/or shares of Yarrow Capital Stock, as applicable, to be exchanged for VYNE Pre-Funded Warrants. As of March 1, 2026, there were 33,323,171 shares of VYNE Common Stock outstanding therefore, VYNE Common Stock to be issued pursuant to the Merger Agreement (including the shares issued to investors in the Yarrow Pre-Closing Financing) will represent greater than 20% of its voting stock outstanding before the issuance.

Accordingly, VYNE is seeking stockholder approval of the issuance of VYNE Common Stock pursuant to the Merger Agreement, including the issuance of VYNE Common Stock underlying the VYNE Pre-Funded Warrants exchanged for the Yarrow Pre-Funded Warrants issued in the Yarrow Pre-Closing Financing under the Nasdaq rules.

On     , 2026 the last trading day before the date of this proxy statement/prospectus, the closing sale price of VYNE Common Stock was $       per share.

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Q:When do you expect the Merger to be consummated?

Stockholder of Record: Shares Registered in Your Name

If you are a stockholder of record, you may vote in person at the VYNE Special Meeting, vote by proxy over the telephone, vote by proxy through the internet or vote by proxy using a proxy card, the form of which is attached as Annex E to this proxy statement/prospectus. Whether or not you plan to attend the meeting, VYNE urges you to vote by proxy to ensure your vote is counted. You may still attend the meeting and vote in person even if you have already voted by proxy.

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Beneficial Owner: Shares Registered in the Name of Broker, Bank or Other Agent

If you are a beneficial owner of shares registered in the name of your broker, bank, or other agent, you should have received voting instructions from that organization rather than from VYNE. Simply follow the voting instructions provided to ensure that your vote is counted. You may vote by telephone or over the internet as instructed by your broker, bank or other agent. To vote in person at the VYNE Special Meeting, you must contact your broker, bank, or other agent and obtain a valid legal proxy in order to attend, participate in and vote at the VYNE Special Meeting. Follow the voting instructions from your broker, bank or other agent, or contact your broker, bank or other agent for instructions.

If, on the Record Date, your shares were registered directly in your name with the transfer agent for the VYNE Common Stock then you are a stockholder of record. As a stockholder of record, you may vote in person at the VYNE Special Meeting or vote early by proxy. Whether or not you plan to attend the VYNE Special Meeting, VYNE encourages you to fill out and return your proxy card or vote by proxy over the telephone or on the internet as instructed above to ensure your vote is counted.

Beneficial Owner: Shares Registered in the Name of a Broker, Fiduciary or Custodian

If you are the beneficial owner and do not direct your broker, fiduciary or custodian how to vote your shares, the question of whether your broker or nominee will still be able to vote your shares depends on whether the New York Stock Exchange (“NYSE”) deems a particular proposal to be a “routine” matter. Your broker, fiduciary or custodian will only be able to vote your shares with respect to proposals considered to be “routine.” Your broker, fiduciary or custodian is not entitled to vote your shares with respect to “non-routine” proposals, resulting in a “broker non-vote” with respect to such proposals. Under the rules and interpretations of the NYSE, “non-routine” matters are matters that may substantially affect the rights or privileges of stockholders, even if management-supported.

STOCKHOLDERS OF RECORD MUST BRING A FORM OF PHOTO IDENTIFICATION SO THEIR SHARE OWNERSHIP CAN BE VERIFIED. A BENEFICIAL OWNER HOLDING SHARES IN “STREET NAME” MUST ALSO BRING AN ACCOUNT STATEMENT OR LETTER FROM HIS OR HER BANK OR BROKERAGE FIRM SHOWING THAT HE OR SHE BENEFICIALLY OWNS SHARES AS OF THE CLOSE OF BUSINESS ON THE RECORD DATE, ALONG WITH A FORM OF PHOTO IDENTIFICATION. STOCKHOLDERS WISHING TO VOTE THEIR SHARES IN PERSON AT THE VYNE SPECIAL MEETING MUST ALSO BRING THE 16-DIGIT CONTROL NUMBER INCLUDED ON THEIR PROXY CARD.

YOUR VOTE IS IMPORTANT AND VYNE STRONGLY ENCOURAGES YOU TO VOTE YOUR SHARES PRIOR TO THE VYNE SPECIAL MEETING.

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Broker non-votes, if any, will be treated as shares present for the purpose of determining the presence of a quorum for the transaction of business at the VYNE Special Meeting. Broker non-votes, if any, will not be counted as “votes properly cast” or “shares entitled to vote” and will therefore have no effect on Proposal Nos. 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10.

Your signed proxy card, telephonic proxy instructions, internet proxy instructions, or written notice must be received by           , 2026, 11:59 p.m. Eastern Time to be counted.

If a VYNE stockholder who owns VYNE shares in “street name” has instructed a broker to vote its shares of VYNE Common Stock, the stockholder must follow directions received from its broker to change and/or revoke those instructions.

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D.F. King & Co., Inc.

48 Wall Street, 22nd Floor

New York, New York 10005

Banks and Brokers, Call Collect: (212) 269-5550

All Others, Call Toll Free: (800) 488-8095

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PROSPECTUS SUMMARY

This summary highlights selected information from this proxy statement/prospectus and may not contain all of the information that is important to you. To better understand the Merger and the proposals being considered at the VYNE Special Meeting, you should read this entire proxy statement/prospectus carefully, including the Merger Agreement and the other annexes to which you are referred in this proxy statement/ prospectus, and the documents incorporated by reference therein. For more information, please see the section titled “Where You Can Find More Information” beginning on page 347 of this proxy statement/prospectus. Except where specifically noted, the following information and all other information contained in this proxy statement/prospectus does not give effect to the proposed reverse stock split described in Proposal No. 2 of this proxy statement/prospectus.

The Companies

VYNE

VYNE is a clinical-stage biopharmaceutical company focused on developing differentiated therapies to treat inflammatory and immune-mediated conditions with high unmet need.

VYNE has exclusive worldwide rights to research, develop and commercialize products containing small molecule bromodomain and extra-terminal domain (“BET”) inhibitors for the treatment of any disease, disorder or condition in humans, which it licensed from Tay Therapeutics Ltd., formerly known as In4Derm Ltd (“Tay”). BET proteins are epigenetic enablers of transcription that regulate the expression of specific genes. Each BET protein consists of two bromodomains (“BD1” and “BD2”) and one end terminal (“ET”) domain. Through VYNE’s transaction with Tay, it obtained access to a library of new small molecule BET inhibitor compounds including those that inhibit both BD1 and BD2 (“pan-BD” BET inhibitor) and that selectively inhibit BD2 (“BD2-selective” BET inhibitor). VYNE initially focused its development efforts with these molecules on immune-mediated inflammatory diseases, which are not being targeted by current BET inhibitors in development.

In August 2025, VYNE initiated a strategic review to evaluate a range of options to maximize stockholder value, including the assessment of its internal pipeline, financing opportunities and strategic alternatives. As part of this process, VYNE evaluated opportunities for repibresib and VYN202, including as part of broader strategic alternatives. In conjunction, VYNE implemented cost reductions to extend its cash runway.

Following the strategic review, on December 17, 2025, VYNE entered into the Merger Agreement with Yarrow and Merger Sub, pursuant to which, among other matters, and subject to the satisfaction or waiver of the conditions set forth in the Merger Agreement, Merger Sub will merge with and into Yarrow, with Yarrow continuing as a wholly owned subsidiary of VYNE and the surviving corporation of the Merger. The Merger is intended to qualify for federal income tax purposes as a tax-free reorganization under the provisions of Section 368(a) of the Code and/or an exchange of shares of Yarrow Capital Stock for VYNE Common Stock under Section 351(a) of the Code.

Following completion of the Merger, the Combined Company plans to focus on advancing YB-101 (also known as GS-098), a clinical-stage thyroid-stimulating hormone receptor (“TSHR”) antibody for the treatment of Graves’ disease (“GD”), and exploring a clinical development plan for the treatment of thyroid eye disease (“TED”) and does not intend to continue development of any of VYNE’s legacy product candidates. However, at this time VYNE is continuing to conduct the activities described in the section titled “VYNE’s Business”, including an ongoing 12-week non-clinical toxicology study of VYN202 in dogs. VYNE may continue to evaluate opportunities for repibresib and VYN202, which may include a sale, license, transfer, disposition, divestiture or other monetization transaction to a third party or to a related party so long as the transaction would not result in material post-closing obligations to the Combined Company without Yarrow’s consent. If the Merger Agreement is terminated, VYNE may pursue other strategic alternatives, including financing opportunities, or liquidation.

Yarrow

Yarrow is a clinical-stage biopharmaceutical company focused on developing novel biotherapeutics to treat autoimmune diseases affecting the thyroid. Yarrow’s lead product candidate, YB-101 (also known as GenSci098), is a humanized, monoclonal antibody targeting the TSHR, which Yarrow plans to develop for the treatment of GD and potentially TED. Both GD and TED are serious and poorly treated autoimmune diseases in which autoantibodies against TSHR attack and overstimulate the receptor, leading to a wide spectrum of thyroidal and extra-thyroidal clinical sequelae.

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YB-101 was designed to selectively bind to TSHR and block autoantibody-induced receptor activation, thereby directly inhibiting the pathogenic activity of thyroid-stimulating autoantibodies that drive disease progression in GD and TED as well as the biological pathway responsible for hyperthyroidism and orbitopathy. Yarrow believes that this novel and targeted approach represents a potential breakthrough for patients with GD and TED and has the potential to address an important unmet need for therapies with differentiated risk-benefit profiles.

In December 2025, Yarrow in-licensed from Changchun Genescience Pharmaceutical Company, Ltd. (“GenSci”) the exclusive rights to develop YB-101 for the treatment of GD and TED outside of China. Yarrow’s development strategy is to advance YB-101 in GD and explore a clinical development plan for TED with the goal of becoming the first company to commercialize an anti-TSHR antibody in the United States and other territories outside of China. YB-101 is currently being evaluated by GenSci in an ongoing Phase 1 single ascending dose (“SAD”) and multiple ascending dose (“MAD”) trial in patients with TED in China. Yarrow submitted the GenSci SAD clinical data to the U.S. Food and Drug Administration (“FDA”) as part of a new IND to support the initiation of a GD trial by Yarrow in the United States, which was cleared by the FDA in March 2026. In addition, third-party clinical data from two SAD trials of another anti-TSHR antibody, K1-70, further support the therapeutic potential of targeting TSHR in patients with GD and TED. Yarrow expects to initiate a combined Phase 2a/Phase 2b trial of YB-101 in patients with GD in the first half of 2026.

Merger Sub

Merger Sub is a direct, wholly owned subsidiary of VYNE and was formed solely for the purpose of carrying out the Merger.

The Merger (see page 119)

Subject to the satisfaction or waiver of the closing conditions set forth in the Merger Agreement, at the Closing, Merger Sub will merge with and into Yarrow, with Yarrow continuing as a wholly owned subsidiary of VYNE and the surviving corporation of the Merger.

VYNE’s Reasons for the Merger (see page 130)

In reaching its decision to approve the Merger Agreement and the transactions contemplated by the Merger Agreement, the VYNE board of directors held numerous meetings, consulted with VYNE’s senior management, legal counsel and financial advisors, and considered a wide variety of factors. Following a thorough process of reviewing and analyzing potential strategic alternatives, the VYNE board of directors considered a number of factors that it viewed as supporting its decision to approve the Merger Agreement, including (but not necessarily presented in any order of relative importance):

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The VYNE board of directors also considered a variety of risks and other countervailing factors related to entering into the Merger, including:

The foregoing information is not intended to be exhaustive but is believed to include a summary of all of the material factors considered by the VYNE board of directors in its consideration of the Merger Agreement and the transactions contemplated thereby. After conducting an overall analysis of these and other factors, including thorough discussions with, and questioning of, VYNE’s management and legal counsel, the VYNE board of directors concluded that the benefits, advantages and opportunities of a potential transaction outweighed the uncertainties and risks described above.

Based on this overall analysis of the factors described above, the VYNE board of directors approved the Merger Agreement, the Merger, and the other transactions contemplated by the Merger Agreement.

Yarrow’s Reasons for the Merger (see page 134)

In the course of reaching its decision to approve the Merger and the Yarrow Pre-Closing Financing, the Yarrow board of directors held numerous meetings, consulted with Yarrow’s senior management, legal counsel and financial advisors, and considered a wide variety of factors. Ultimately, the Yarrow board of directors concluded that a merger with VYNE, together with the additional financing committed from the Yarrow Pre-Closing Financing, was the best option to generate capital resources to support the advancement of Yarrow’s pipeline and fund the Combined Company.

Additional factors the Yarrow board of directors considered included the following (which factors are not necessarily presented in any order of relative importance):

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The Yarrow board of directors also considered a number of uncertainties and risks in its deliberations concerning the Merger and the other transactions contemplated by the Merger Agreement, including the following:

Interests of VYNE’s Directors and Executive Officers in the Merger (see page 143)

In considering the recommendation of the VYNE board of directors with respect to approving the Merger, stockholders should be aware that VYNE’s directors and executive officers have interests in the Merger that are different from, or in addition to, the interests of VYNE stockholders generally. These interests may present them with actual or potential conflicts of interest. These interests include the following:

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Certain material payments to the executives of VYNE are factored into the calculation of Net Cash as deductions, including any bonus, retention payments, including the Retention Bonuses (as defined below), severance, change-in-control payments or similar payment obligations (including payments with “single-trigger” provisions triggered at and as of the consummation of the transactions contemplated hereby) that are due or payable to any director, officer, employee or consultant as a result of the consummation of the Transactions or any VYNE Legacy Transaction, together with any payroll taxes associated therewith. This includes compensation referred to as “golden parachute” compensation by the applicable SEC disclosure rules and is further discussed in greater detail in the section below titled “The Merger — Interests of VYNE Directors and Executive Officers in the Merger —  Golden Parachute Compensation” on page 147 of this proxy statement/prospectus. The amount of the pre-closing cash dividend payable to VYNE stockholders is directly affected by the amount of payments made to VYNE executives at Closing. Any increase in such payments will reduce Net Cash and, accordingly, reduce the aggregate amount of the pre-closing cash dividend.

The VYNE board of directors was aware of these potential conflicts of interest and considered them, among other matters, in reaching its decision to approve the Merger Agreement and the Merger, and to recommend that VYNE stockholders approve the Merger as contemplated by this proxy statement/prospectus.

Interests of Yarrow Directors and Executive Officers in the Merger (see page 149)

In considering the recommendation of the Yarrow board of directors with respect to approving the Merger, stockholders should be aware that Yarrow’s directors and executive officers have interests in the Merger that are different from, or in addition to, the interests of Yarrow stockholders generally. These interests may present them with actual or potential conflicts of interest. These interests include the following:

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The Yarrow board of directors was aware of these potential conflicts of interest and considered them, among other matters, in reaching its decision to approve the Merger Agreement and the Merger, and to recommend that Yarrow stockholders approve the Merger as contemplated by this proxy statement/ prospectus.

Opinion of VYNE’s Financial Advisor (see page 136)

VYNE retained LifeSci Capital to render an opinion to the VYNE board of directors as to the fairness of the Exchange Ratio, from a financial point of view, proposed to be paid by VYNE pursuant to the Merger Agreement (the “LifeSci Capital Opinion”). On December 16, 2025, at the request of the VYNE board of directors, LifeSci Capital rendered an oral opinion, subsequently confirmed by delivery of the LifeSci Capital Opinion dated December 16, 2025, to the VYNE board of directors, that the Exchange Ratio to by paid by VYNE was fair, from a financial point of view, to VYNE as of the date of the LifeSci Capital Opinion and based upon and subject to the various assumptions, procedures followed, matters considered and qualifications and limitations set forth therein. LifeSci Venture Partners, an affiliate of LifeSci Capital, has committed to purchase $10 million of shares of Yarrow Common Stock and Yarrow Pre-Funded Warrants in the Yarrow Pre-Closing Financing and previously purchased $10 million of shares of Yarrow Preferred Stock concurrently with the signing of the Merger Agreement. As a result, LifeSci Capital could be viewed to have a conflict of interest because its affiliate has a financial interest in the consummation of the Merger and the Yarrow Pre-Closing Financing, which could create the appearance that its advice may be influenced by interests that differ from, or are in addition to, those of VYNE stockholders.

The full text of the LifeSci Capital Opinion, which describes the various assumptions made, procedures followed, matters considered and the qualifications and limitations upon the review undertaken by LifeSci Capital in preparing its opinion, is attached as Annex F to this proxy statement/prospectus and is incorporated herein by reference. LifeSci Capital’s financial advisory services and opinion were provided for the information and assistance of the VYNE board of directors (in their capacity as directors and not in any other capacity) in connection with and for purposes of the VYNE board of directors’ consideration of the transactions contemplated by the Merger Agreement (the “Transaction”) and the LifeSci Capital Opinion addressed only the fairness, from a financial point of view, as of the date thereof, to VYNE of the Exchange Ratio proposed to be paid by VYNE pursuant to the terms of the Merger Agreement. The opinion of LifeSci Capital did not address any other term or aspect of the Merger Agreement or the Merger and does not constitute a recommendation to any stockholder of VYNE or any other person as to how such stockholder or other person should vote with respect to the Merger or otherwise act with respect to the Transaction or any other matter.

The full text of the LifeSci Capital Opinion should be read carefully in its entirety for a description of the various assumptions made, procedures followed, matters considered and the qualifications and limitations upon the review undertaken by LifeSci Capital in preparing its opinion.

Overview of the Merger Agreement and Agreements Related to the Merger Agreement

Merger Consideration (see page 160)

At the Effective Time, upon the terms and subject to the conditions set forth in the Merger Agreement, (i) each then-outstanding share of Yarrow Capital Stock (including shares of Yarrow Common Stock issued in the Yarrow Pre-Closing Financing), excluding any shares of Yarrow Capital Stock to be cancelled pursuant to the Merger Agreement and any dissenting shares, will be converted into the right to receive a number of shares of VYNE Common Stock and/or VYNE Pre-Funded Warrants, as applicable, equal to the Exchange Ratio (described in more detail in the section titled “The Merger Agreement — Exchange Ratio” beginning on page 161 of this proxy statement/ prospectus), (ii) each then-outstanding Yarrow Option will be converted into and become an option to purchase shares of VYNE Common Stock on the existing terms and conditions (including with respect to vesting and accelerated vesting), subject to adjustment as set forth in the Merger Agreement, and (iii) each then-outstanding and unexercised Yarrow Pre-Funded Warrant will be converted into a VYNE Pre-Funded Warrant, subject to adjustment as set forth in the Merger Agreement and the form of pre-funded warrant.

Immediately after the Merger, VYNE securityholders as of immediately prior to the Merger are expected to own approximately 3.0% of the outstanding shares of capital stock of the Combined Company on a fully-diluted basis and former holders of Yarrow securities are expected to own approximately 97.0% of the outstanding shares of capital stock of the Combined Company on a fully-diluted basis. Under certain circumstances further described in the Merger Agreement, the ownership percentages may be adjusted up or down including, but not limited to, if VYNE’s Net Cash as of Closing is lower than $0.

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In addition, prior to the Effective Time, the VYNE board of directors expects to declare the Cash Dividend to the pre-Merger VYNE stockholders equal in the aggregate to VYNE’s reasonable, good faith approximation of the amount by which VYNE’s Net Cash (as determined pursuant to the Merger Agreement) is expected to exceed $0. VYNE management currently estimates that the aggregate amount of cash to be distributed to stockholders of record as of the record date for the Cash Dividend will be approximately $14.5 million to $16.5 million.

Treatment of Yarrow Options (see page 164)

Under the terms of the Merger Agreement, VYNE will assume Yarrow’s 2025 Equity Incentive Plan and each option to purchase shares of Yarrow Common Stock that is outstanding and unexercised immediately prior to the Effective Time, whether or not vested, will be assumed and converted into an option to purchase shares of VYNE Common Stock.

Accordingly, from and after the Effective Time: (i) each outstanding Yarrow Option assumed by VYNE may be exercised solely for shares of VYNE Common Stock; (ii) the number of shares of VYNE Common Stock subject to each outstanding Yarrow Option assumed by VYNE will be determined by multiplying (A) the number of shares of Yarrow Common Stock that were subject to such Yarrow Option assumed by VYNE, as in effect immediately prior to the Effective Time, by (B) the Exchange Ratio, and rounding the resulting number down to the nearest whole number of shares of VYNE Common Stock; and (iii) the per share exercise price of each Yarrow Option assumed by VYNE will be determined by dividing (A) the per share exercise price of such Yarrow Option, as in effect immediately prior to the Effective Time, by (B) the Exchange Ratio, and rounding the resulting exercise price up to the nearest whole cent. Each Yarrow Option assumed by VYNE will otherwise continue in full force and effect and the term, exercisability, vesting schedule, acceleration rights and other terms and conditions of such Yarrow Option will otherwise remain unchanged.

Each Yarrow stock option shall, in accordance with its terms, continue to be subject to further adjustment as appropriate to reflect any stock split, division or subdivision of shares, stock dividend, reverse stock split, consolidation of shares, reclassification, recapitalization or other similar transaction with respect to shares of VYNE Common Stock subsequent to the Effective Time. In addition, the Combined Company’s compensation committee will succeed to the authority and responsibility of the Yarrow board of directors as administrator of Yarrow’s 2025 Equity Incentive Plan.

Treatment of Yarrow Pre-Funded Warrants (see page 164)

Under the terms of the Merger Agreement, each Yarrow Pre-Funded Warrant issued pursuant to the Yarrow Pre-Closing Financing that is outstanding and unexercised immediately prior to the Effective Time, whether or not vested, will be converted into a VYNE Pre-Funded Warrant.

Accordingly, from and after the Effective Time: (i) each outstanding Yarrow Pre-Funded Warrant assumed by VYNE may be exercised solely for shares of VYNE Common Stock; (ii) the number of shares of VYNE Common Stock subject to each outstanding Yarrow Pre-Funded Warrant assumed by VYNE will be determined by multiplying (A) the number of shares of Yarrow Common Stock issuable upon exercise of the Yarrow Pre-Funded Warrant that were subject to such Yarrow Pre-Funded Warrant, as in effect immediately prior to the Effective Time, by (B) the Exchange Ratio, and rounded up to the next whole share of VYNE Common Stock to the extent the aggregate amount of fractional shares of VYNE Common Stock such holder would otherwise be entitled to is equal to or exceeds 0.50; and (iii) the per share exercise price for the VYNE Common Stock issuable upon exercise of each Yarrow Pre-Funded Warrant assumed by VYNE will be determined by dividing (A) the per share exercise price of VYNE Common Stock subject to such Yarrow Pre-Funded Warrant as in effect immediately prior to the Effective Time, by (B) the Exchange Ratio, and rounding the resulting exercise price up to the nearest whole cent. Each Yarrow Pre-Funded Warrant assumed by VYNE will otherwise continue in full force and effect and the term, any restriction on the exercise and other provisions of such Yarrow Pre-Funded Warrant will otherwise remain unchanged.

Each Yarrow Pre-Funded Warrant shall, in accordance with its terms, continue to be subject to further adjustment as appropriate to reflect any stock split, division or subdivision of shares, stock dividend, reverse stock split, consolidation of shares, reclassification, recapitalization or other similar transaction with respect to shares of VYNE Common Stock subsequent to the Effective Time.

Treatment of VYNE Common Stock and VYNE Options (see page 165)

Except as contemplated by the proposed increase in the number of authorized shares of VYNE Common Stock described in Proposal No. 3 of this proxy statement/prospectus and the proposed reverse stock split of issued and outstanding VYNE Common Stock described in Proposal No. 2 of this proxy statement/prospectus, VYNE Common Stock will remain unaffected by the Merger.

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Under the terms of the Merger Agreement, prior to the Closing, the VYNE board of directors will accelerate the vesting of all equity awards of VYNE then outstanding but not then vested or exercisable, and cancel each option to acquire shares of VYNE Common Stock, in accordance with the terms of the Merger Agreement. At the Effective Time, (i) each In-the-Money VYNE Option will be cancelled and converted into the right to receive an amount in cash, without interest, less any applicable tax withholding, equal to the product obtained by multiplying (A) the excess of the VYNE Closing Price over the exercise price per share of VYNE Common Stock underlying such VYNE Option by (B) the number of shares of VYNE Common Stock underlying such VYNE Option and (ii) each Out-of-the-Money VYNE Option will be cancelled for no consideration.

Conditions to the Completion of the Merger (see page 173)

To complete the Merger, VYNE stockholders must approve Proposal No. 1 and Proposal No. 2 and Yarrow stockholders must adopt the Merger Agreement and approve the Merger and the related transactions contemplated by the Merger Agreement. Additionally, each of the other closing conditions set forth in the Merger Agreement must be satisfied or waived.

Non-Solicitation (see page 169)

The Merger Agreement contains non-solicitation provisions prohibiting VYNE and Yarrow from soliciting a competing transaction. Each of VYNE and Yarrow have agreed that, subject to certain exceptions, VYNE and Yarrow and any of their respective subsidiaries will not, nor will either party or any of its subsidiaries authorize any of the directors, officers, employees, investment bankers, financial advisors, attorneys, accountants or other advisors, agents or representatives retained by it or any of its subsidiaries to, directly or indirectly:

Board Recommendation Change (see page 171)

Neither the Yarrow board of directors nor VYNE board of directors may change its recommendation in favor of the Merger, except that prior to receipt by such party of its stockholder approval, such party’s board of directors may effect a change in recommendation as a result of a material development or change in circumstances (“Intervening Event”), or with respect to a superior offer that did not result from a material breach of the Merger Agreement if:

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In the event of any material amendment to any superior offer, the party considering the superior offer would be required to provide the other party with notice of such material amendment and there would be a new three-business day period following such notification during which the parties would be obligated to comply again with the requirements described above.

In the case of an Intervening Event, the party suffering such event shall promptly notify the other party before effecting a change in recommendation. The written notice is required to state the material facts and circumstances related to the applicable Intervening Event and that such party’s board of directors intends to make a change in recommendation.

Termination of the Merger Agreement (see page 174)

Either VYNE or Yarrow may terminate the Merger Agreement under certain circumstances, which would prevent the Merger from being consummated.

Termination Fee (see page 175)

If the Merger Agreement is terminated under certain circumstances, VYNE could be required to pay Yarrow a termination fee of $1,000,000 or Yarrow could be required to pay VYNE a termination fee of $1,000,000.

Support Agreements (see page 177)

RTW Investments, OrbiMed, Janus Henderson Investors, venBio Partners, Logos Capital and LifeSci Venture Partners, as stockholders of Yarrow (solely in their respective capacities as Yarrow stockholders) holding approximately 95.9% of the outstanding shares of Yarrow Capital Stock, have entered into support agreements with VYNE and Yarrow to vote all of their shares of Yarrow capital stock in favor of the adoption and approval of the Merger Agreement and the transactions contemplated thereby (the “Yarrow Support Agreements”).

Certain stockholders of VYNE beneficially holding approximately 3.0% of the outstanding shares of VYNE Common Stock have entered into support agreements with VYNE and Yarrow to vote all of their shares of VYNE Common Stock in favor of the adoption and approval of the Merger Agreement and the transactions contemplated thereby and the Reverse Stock Split and against any alternative Acquisition Proposals (the “VYNE Support Agreements”).

Lock-Up Agreements (see page 177)

Certain of VYNE’s and Yarrow’s executive officers and directors have entered into lock-up agreements, pursuant to which such parties have agreed not to, except in limited circumstances, offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, or otherwise transfer or dispose of, directly or indirectly, any shares of VYNE Common Stock or any securities convertible into or exercisable or exchangeable for VYNE Common Stock, currently or thereafter owned, but excluding, as applicable, shares purchased by existing Yarrow stockholders in the Yarrow Pre-Closing Financing (including any shares of VYNE Common Stock issuable upon exercise of VYNE Pre-Funded Warrants issued in exchange for Yarrow Pre-Funded Warrants sold in the Yarrow Pre-Closing Financing), until 180 days after the Effective Time.

Securities Purchase Agreement and Registration Rights Agreement (see pages 177 and 179)

Concurrently with the execution and delivery of the Merger Agreement, certain institutional and accredited investors of Yarrow entered into the Securities Purchase Agreement with Yarrow, pursuant to which such investors have agreed to purchase, immediately prior to the Merger, shares of Yarrow Common Stock or, in lieu thereof, Yarrow Pre-Funded Warrants, representing an aggregate commitment of approximately $100 million in the Yarrow Pre-Closing Financing.

The shares of Yarrow Common Stock and Yarrow Pre-Funded Warrants that are issued in the Yarrow Pre- Closing Financing will be or will have the right to be, respectively, converted into shares of VYNE Common Stock in the Merger.

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The Securities Purchase Agreement contains customary representations and warranties of Yarrow and also contains customary representations and warranties of the purchaser parties thereto.

The Securities Purchase Agreement also contemplates Yarrow and the investors participating in the Yarrow Pre-Closing Financing entering into a registration rights agreement at the closing of the Yarrow Pre- Closing Financing, pursuant to which, among other things, the Combined Company will agree to provide for the registration and resale of certain shares of VYNE Common Stock that are held by the investors participating in the Yarrow Pre-Closing Financing from time to time pursuant to Rule 415.

Management Following the Merger

The following table sets forth the name, age as of                 , 2026, and position of each of the individuals who are expected to serve as executives and directors of the Combined Company following completion of the Merger:

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U.S. Federal Income Tax Considerations of the Merger (see page 151)

The Merger is intended to qualify as a “reorganization” within the meaning of Section 368(a) of the Code and/or an exchange of shares of Yarrow Capital Stock for VYNE Common Stock under Section 351(a) of the Code. Assuming the Merger so qualifies, subject to the limitations and qualifications described in the section titled “The Merger — U.S. Federal Income Tax Considerations of the Merger” beginning on page 151 of this proxy statement/prospectus, a U.S. Holder of Yarrow Capital Stock will not recognize gain or loss upon the exchange of its Yarrow Capital for VYNE Common Stock. Since VYNE stockholders will not sell, exchange or dispose of any shares of VYNE Common Stock as a result of the Merger, there will be no material U.S. federal income tax considerations to VYNE stockholders as a result of the Merger. For a more detailed discussion of the U.S. federal income tax considerations of the Merger, see the section titled “The Merger — U.S. Federal Income Tax Considerations of the Merger,” beginning on page 151 of this proxy statement/prospectus.

Risk Factors (see page 27)

Both VYNE and Yarrow are subject to various risks associated with their businesses and their industries. In addition, the Merger, including the possibility that the Merger may not be completed, poses a number of risks to each company and its respective securityholders, including the following risks:

Risks Related to the Proposed Merger:

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Risks Related to the Proposed Reverse Stock Split:

Risks Related to VYNE:

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Risks Related to Yarrow:

Risks Related to the Ownership of the Combined Company Common Stock:

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These risks and other risks are discussed in greater detail under the section titled “Risk Factors” beginning on page 27 of this proxy statement/prospectus. VYNE and Yarrow both encourage you to read and consider all of these risks carefully.

Regulatory Approvals (see page 172)

Each of VYNE and Yarrow will use commercially reasonable efforts to file or otherwise submit, as soon as practicable after the date of the Merger Agreement, all applications, notices, reports and other documents reasonably required to be filed by such party with or otherwise submitted by such party to any governmental authority with respect to the transactions contemplated by the Merger Agreement, if any, and to submit promptly any additional information requested by any such governmental authority.

Nasdaq Stock Market Listing (see page 156)

VYNE has filed an initial listing application for the Combined Company common stock with Nasdaq. If such application is accepted, VYNE anticipates that the Combined Company common stock will be listed on Nasdaq following the Closing under the trading symbol “YARW.” It is a condition to the consummation of the Merger that VYNE will receive confirmation from Nasdaq that the Combined Company has been approved for listing on Nasdaq, but there can be no assurance such listing condition will be met or that VYNE will obtain such confirmation from Nasdaq. If such listing condition is not met or if such confirmation is not obtained, the Merger will not be consummated unless the condition is waived. The Nasdaq condition set forth in the Merger Agreement is not expected to be waived by the applicable parties.

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Anticipated Accounting Treatment (see page 156)

The Merger is expected to be treated by VYNE as a reverse merger and will be accounted for as an in- substance reverse recapitalization of VYNE by Yarrow in accordance with U.S. Generally Accepted Accounting Principles (“GAAP”) as, at close, the transaction is, in essence, the issuance of equity by Yarrow for VYNE’s net assets, consisting of nominal assets and liabilities at the time of the Merger. For accounting purposes, Yarrow is considered to be acquiring the assets and liabilities of VYNE in this transaction based on the terms of the Merger Agreement and other factors, including: (i) Yarrow’s equity holders will own a substantial majority of the voting rights in the Combined Company; (ii) Yarrow’s largest stockholder will retain the largest interest in the Combined Company; (iii) Yarrow will designate all of the initial members of the board of directors of the Combined Company; and (iv) a member of VYNE’s and members of Yarrow’s executive management team will become the management of the Combined Company. The Combined Company will be named Yarrow Bioscience, Inc. In addition, Yarrow concluded that any in-process research and development assets of VYNE at the closing of the Merger would be de-minimis and any potential future royalties from VYNE’s out-licensed product, Finacea foam, represent a potential passive revenue stream rather than ongoing operating activities. Formulation and use patents for Finacea foam currently expire in 2027 and 2029, respectively, but may experience an earlier loss of exclusivity due to generic entry. Accordingly, upon the closing of the Merger, VYNE is expected to have no or nominal operations for accounting purposes and the Merger is expected to be treated as the equivalent of Yarrow issuing stock to acquire the net assets of VYNE. As a result of the Merger, the net assets of VYNE will be stated at fair value, which approximates carrying value, with no goodwill or other intangible assets recorded, and the historical results of operations prior to the Merger will be those of Yarrow. The direct and incremental costs related to the transaction will be treated as a reduction of the net proceeds received within additional paid- in-capital. See the “Unaudited Pro Forma Condensed Combined Financial Information” elsewhere in this proxy statement/prospectus for additional information.

Appraisal Rights and Dissenters’ Rights (see page 157)

Holders of VYNE Common Stock are not entitled to appraisal rights in connection with the Merger under Delaware law. Holders of Yarrow capital stock are entitled to appraisal rights in connection with the Merger under Delaware law.

Comparison of Stockholder Rights (see page 331)

VYNE and Yarrow are incorporated under the laws of the State of Delaware and, accordingly, the rights of the stockholders of each are currently, and will continue to be, governed by the Delaware General Corporation Law (“DGCL”). If the Merger is completed, Yarrow stockholders will become VYNE stockholders, and their rights will be governed by the DGCL, VYNE’s amended and restated bylaws (the “VYNE Bylaws”) and the VYNE Charter, as may be further amended by Proposal Nos. 2 and 3 if approved by VYNE stockholders at the VYNE Special Meeting. The rights of VYNE stockholders contained in the VYNE Charter and the VYNE Bylaws differ from the rights of Yarrow stockholders under Yarrow’s certificate of incorporation and Yarrow’s amended and restated bylaws, as more fully described under the section titled “Comparison of Rights of Holders of VYNE Capital Stock and Yarrow Capital Stock” beginning on page 331 of this proxy statement/ prospectus.

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MARKET PRICE AND DIVIDEND INFORMATION

The VYNE Common Stock is currently listed on The Nasdaq Capital Market under the symbol “VYNE.”

The closing price of VYNE Common Stock on December 16, 2025, the last day of trading prior to the announcement of the Merger, as reported on Nasdaq, was $0.40 per share. The closing price of VYNE Common Stock on          , 2026, as reported on Nasdaq, was $      per share.

Because the market price of VYNE Common Stock is subject to fluctuation, the market value of the shares of VYNE Common Stock that Yarrow stockholders will be entitled to receive in the Merger may increase or decrease.

Yarrow is a private company, and shares of Yarrow Common Stock and Yarrow Preferred Stock are not publicly traded.

Assuming approval of Proposal Nos. 1 and 2 and successful application for initial listing with Nasdaq, following the consummation of the Merger, shares of the Combined Company common stock are expected to trade on Nasdaq under VYNE’s new name, “Yarrow Bioscience, Inc.,” and new trading symbol “YARW.”

As of      , 2026, the record date for the VYNE Special Meeting, there were approximately      registered holders of record of VYNE Common Stock. As of       , 2026, Yarrow had      holders of record of Yarrow Common Stock and      holders of record of Yarrow Preferred Stock. For detailed information regarding the beneficial ownership of certain VYNE and Yarrow stockholders, see the sections of this proxy statement/prospectus titled “Principal Stockholders of Yarrow” and “Principal Stockholders of VYNE.”

Dividends

VYNE has never declared or paid any cash dividends on its common stock and, other than the Cash Dividend, does not anticipate paying cash dividends on its common stock for the foreseeable future. Notwithstanding the foregoing, any determination to pay cash dividends subsequent to the Merger will be at the discretion of the Combined Company’s then-current board of directors and will depend upon a number of factors, including the Combined Company’s results of operations, financial condition, future prospects, contractual restrictions, restrictions imposed by applicable law and other factors the then-current board of directors deems relevant.

Yarrow has never paid or declared any cash dividends on Yarrow Capital Stock. If the Merger does not occur, Yarrow does not anticipate paying any cash dividends on the Yarrow Capital Stock in the foreseeable future, and Yarrow intends to retain all available funds and any future earnings to fund the development and expansion of its business. Any future determination to pay dividends will be at the discretion of the Yarrow board of directors and will depend upon a number of factors, including its results of operations, financial condition, future prospects, contractual restrictions, and restrictions imposed by applicable laws and other factors the Yarrow board of directors deems relevant.

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RISK FACTORS

The Combined Company will be faced with a market environment that cannot be predicted and that involves significant risks, many of which will be beyond its control. In addition to the other information contained or incorporated by reference in this proxy statement/prospectus, you should carefully consider the material risks described below before deciding how to vote your shares of VYNE Common Stock. You should also read and consider the other information in this proxy statement/prospectus. Please see the section titled “Where You Can Find More Information” beginning on page 347 of this proxy statement/prospectus for further information. Moreover, some of the factors, events and contingencies discussed below may have occurred in the past, but the disclosures below are not representations as to whether or not the factors, events or contingencies have occurred in the past and instead reflect our beliefs and opinions as to the factors, events, or contingencies that could materially and adversely affect us in the future.

Risks Related to the Proposed Merger

Failure to complete, or delays in completing, the potential Merger with Yarrow could materially and adversely affect VYNE’s results of operations, business, financial results and/or common stock price.

On December 17, 2025, VYNE entered into the Merger Agreement with Yarrow pursuant to which, among other matters, and subject to the satisfaction or waiver of the conditions set forth in the Merger Agreement, Merger Sub will merge with and into Yarrow, with Yarrow continuing as a wholly owned subsidiary of VYNE and the surviving corporation of the Merger. Consummation of the Merger is subject to certain closing conditions, a number of which are not within VYNE’s control. Any failure to satisfy these required conditions to closing may prevent, delay or otherwise materially adversely affect the completion of the transaction. VYNE cannot predict with certainty whether or when any of the required closing conditions will be satisfied or if another uncertainty may arise and cannot assure you that it will be able to successfully consummate the Merger as currently contemplated under the Merger Agreement or at all.

VYNE’s efforts to complete the Merger could cause substantial disruptions in, and create uncertainty surrounding, its business, which may materially adversely affect its results of operation and its business. Uncertainty as to whether the Merger will be completed in a timely manner or at all may affect VYNE’s ability to retain and motivate existing employees. Uncertainty as to whether the Merger will be completed in a timely manner or at all could adversely affect VYNE’s business and its relationship with collaborators, suppliers, vendors, regulators and other business partners. The adverse effects of the pendency of the transaction could be exacerbated by any delays in completion of the transaction or termination of the Merger Agreement.

If the conditions to the Merger are not satisfied or waived, the Merger may not occur.

Even if the Merger is approved by the stockholders of Yarrow and VYNE, specified conditions must be satisfied or, to the extent permitted by applicable law, waived to complete the Merger. These conditions are set forth in the Merger Agreement and described further in the section titled “The Merger Agreement” of this proxy statement/prospectus. VYNE cannot assure you that all of the conditions to the consummation of the Merger will be satisfied or waived. If the conditions are not satisfied or waived, the Merger may not occur or the closing may be delayed.

VYNE and Yarrow may mutually agree to waive the condition to the Merger requiring approval for listing on Nasdaq, and if such condition is waived, the Combined Company’s stock may not be listed on Nasdaq following completion of the Merger.

Pursuant to the Merger Agreement, VYNE agreed, to the extent required by the rules and regulations of Nasdaq, to use its commercially reasonable efforts to cause the shares of VYNE Common Stock being issued in the Merger to be approved for listing on Nasdaq at or prior to the Effective Time. Additionally, under the Merger Agreement, each of VYNE’s and Yarrow’s obligation to complete the Merger is subject to the satisfaction or waiver by each of the parties of various conditions, including that the shares of VYNE Common Stock to be issued in the Merger have been approved for listing (subject to official notice of issuance) on Nasdaq as of the closing of the Merger. In the event that the shares of VYNE Common Stock to be issued in the Merger are not approved for listing on Nasdaq, it is possible (although not likely) that VYNE and Yarrow may mutually agree to waive the applicable condition and nonetheless proceed with completing the Merger. If such condition is waived, VYNE will not recirculate an updated proxy statement/ prospectus, nor will it solicit a new vote of stockholders prior to proceeding with the Merger. If VYNE proceeds with the Merger in these circumstances, the Combined Company’s stock may not be listed on Nasdaq.

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If the Combined Company’s stock is not listed on Nasdaq following completion of the Merger, trading of the shares could be conducted in the over-the-counter market or on an electronic bulletin board established for unlisted securities such as the Pink Sheets or the OTC Bulletin Board. In such event, it is likely that there would be significantly less liquidity in the trading of the Combined Company common stock, decreases in institutional and other investor demand for the shares, a reduction in coverage by securities analysts, a decrease in market making activity and information available concerning trading prices and volume, and fewer broker dealers willing to execute trades in the Combined Company common stock. Also, it may be difficult for the Combined Company to raise additional capital if the Combined Company common stock is not listed on a major exchange. The occurrence of any of these events could result in a further decline in the market price of the Combined Company common stock and could have a material adverse effect on the Combined Company.

The Exchange Ratio for the Merger will not change or otherwise be adjusted based on the market price of VYNE Common Stock.

Applying the Exchange Ratio, based on VYNE’s and Yarrow’s capitalization as of December 17, 2025 and taking into account VYNE’s current cash position, (i) each then-outstanding share of Yarrow Capital Stock (including shares of Yarrow Common Stock issued in the Yarrow Pre-Closing Financing), excluding any shares to be cancelled pursuant to the Merger Agreement and excluding dissenting shares, will be converted into the right to receive a number of shares of VYNE Common Stock and/or VYNE Pre-Funded Warrants, as applicable, equal to 35.8667, (ii) each then-outstanding Yarrow Option will be converted into and become an option to purchase shares of VYNE Common Stock on the existing terms and conditions (including with respect to vesting and accelerated vesting), subject to adjustment as set forth in the Merger Agreement, and (iii) each then-outstanding and unexercised Yarrow Pre-Funded Warrant will be converted into VYNE Pre-Funded Warrant, subject to adjustment as set forth in the Merger Agreement and the form of pre-funded warrant. Applying the Exchange Ratio, the former Yarrow securityholders immediately before the Merger are expected to own approximately 97.0% of the aggregate number of shares of the Combined Company’s capital stock following the Merger (on a fully-diluted basis, and subject to dilution from any equity issued by Yarrow after December 17, 2025 and before the closing), and VYNE securityholders immediately before the Merger are expected to own approximately 3.0% of the aggregate number of shares of the Combined Company capital stock following the Merger (on a fully-diluted basis), subject to certain assumptions, including, but not limited to, that VYNE’s Net Cash as of Closing will be approximately $0, after giving effect to the Cash Dividend, which is expected to be approximately $14.5 to $16.5 million.

Any changes in the market price of VYNE Common Stock before the completion of the Merger will not affect the number of shares Yarrow stockholders will be entitled to receive pursuant to the Merger Agreement. Therefore, if before the completion of the Merger, the market price of VYNE Common Stock increases from the market price on the date of the Merger Agreement, then Yarrow stockholders could receive merger consideration with substantially more value for their shares of Yarrow Capital Stock than the parties had negotiated when they established the Exchange Ratio. Similarly, if before the completion of the Merger, the market price of VYNE Common Stock declines from the market price on the date of the Merger Agreement, then Yarrow stockholders could receive merger consideration with substantially lower value. The Merger Agreement does not include a price-based termination right.

The issuance of VYNE Common Stock, including the shares of VYNE Common Stock issued in exchange for shares of Yarrow Common Stock issued in the Yarrow Pre-Closing Financing, to Yarrow stockholders pursuant to the Merger Agreement and the resulting change in control from the Merger, and the Reverse Stock Split, must be approved by VYNE stockholders, and the Merger Agreement and transactions contemplated thereby must be approved by the Yarrow stockholders. Failure to obtain these approvals would prevent the closing of the Merger.

Before the Merger can be completed, VYNE stockholders must approve, among other things, the issuance of VYNE Common Stock, including shares of Yarrow Common Stock issued in the Yarrow Pre-Closing Financing, to Yarrow stockholders pursuant to the Merger Agreement and the resulting change in control from the Merger and the Reverse Stock Split, and Yarrow stockholders must adopt the Merger Agreement and approve the Merger and the related transactions. Failure to obtain the required stockholder approvals may result in a material delay in, or the abandonment of, the Merger. Any delay in completing the Merger may materially adversely affect the timing and benefits that are expected to be achieved from the Merger.

The Merger may be completed even though a material adverse effect may result from the announcement of the Merger, industry-wide changes or other causes.

In general, neither VYNE nor Yarrow is obligated to complete the Merger if there is a material adverse effect affecting the other party between December 17, 2025, the date of the Merger Agreement, and the closing of the Merger. However, certain types of causes are excluded from the concept of a “material adverse effect.” Such exclusions include, but are not limited to, changes in general economic or political conditions, industry-wide changes, changes resulting from the announcement of the Merger, natural disasters,

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pandemics, other public health events or force majeure events and changes in U.S. generally accepted accounting principles. Therefore, if any of these events were to occur and adversely affect VYNE or Yarrow, the other party would still be obliged to consummate the closing of the Merger notwithstanding such material adverse effect. If any such adverse effects occur and VYNE consummates the closing of the Merger, the stock price of the Combined Company may suffer. This in turn may reduce the value of the Merger to the stockholders of VYNE, Yarrow or both.

If the Merger is not completed, VYNE’s stock price may decline significantly.

The market price of VYNE Common Stock is subject to significant fluctuations. Market prices for securities of pharmaceutical, biotechnology and other life science companies have historically been particularly volatile. In addition, the market price of VYNE Common Stock will likely be volatile based on whether stockholders and other investors believe that VYNE can complete the Merger or otherwise raise additional capital to support VYNE’s operations if the Merger is not consummated and another strategic transaction cannot be identified, negotiated and consummated in a timely manner, if at all. The volatility of the market price of VYNE Common Stock has been and may be exacerbated by low trading volume.

Additional factors that may cause the market price of VYNE Common Stock to fluctuate include:

Moreover, the stock markets in general have experienced substantial volatility that has often been unrelated to the operating performance of individual companies. These broad market fluctuations may also adversely affect the trading price of VYNE Common Stock. In the past, following periods of volatility in the market price of a company’s securities, stockholders have often instituted class action securities litigation against such companies.

If VYNE completes the Merger, the Combined Company will need to raise additional capital, including by potentially issuing equity securities or incurring debt, which may cause significant dilution to the Combined Company’s stockholders or restrict the Combined Company’s operations.

In connection with the Merger, Yarrow entered into the Securities Purchase Agreement with certain investors, including existing investors of Yarrow, pursuant to which the investors agreed to purchase, in the aggregate, $100.0 million in shares of Yarrow Common Stock and Yarrow Pre-Funded Warrants in the Yarrow Pre-Closing Financing immediately prior to the closing of the Merger. Although the closing of the Yarrow Pre-Closing Financing is not a condition to the closing of the Merger with Yarrow, the closing of the Yarrow Pre-Closing Financing is conditioned upon the satisfaction or waiver of the conditions to the closing of the Merger as well as certain other conditions. The shares of Yarrow Common Stock and the Yarrow Pre-Funded Warrants issued in the Yarrow Pre-Closing Financing will result in dilution to all securityholders of the Combined Company (i.e., both VYNE’s pre-Merger securityholders and former Yarrow securityholders).

In addition, the closing of the Yarrow Pre-Closing Financing is not a condition to the closing of the Merger, therefore VYNE stockholders are being asked to vote on the Merger without assurance that the proceeds of the Yarrow Pre-Closing Financing will be available at the time the Merger is consummated. If the Merger closes before the financing proceeds are received, the Combined Company would initially operate using its then-available cash resources and may need to adjust the timing or scope of certain expenditures until such proceeds are received or alternative capital is obtained.

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Additional or alternative financing may not be available to the Combined Company when it is needed or may not be available on favorable terms. To the extent that the Combined Company raises additional capital by issuing equity securities, such financing will cause additional dilution to all securityholders of the Combined Company, including VYNE’s pre-Merger securityholders and Yarrow’s former securityholders. It is also possible that the terms of any new equity securities may have preferences over the Combined Company common stock. Any debt financing the Combined Company enters into may involve covenants that restrict its operations. These restrictive covenants may include limitations on additional borrowing and specific restrictions on the use of the Combined Company’s assets, as well as prohibitions on its ability to create liens, pay dividends, redeem its stock or make investments. In addition, if the Combined Company raises additional funds through licensing arrangements, it may be necessary to grant licenses on terms that are not favorable to the Combined Company.

Some of VYNE’s and Yarrow’s directors and executive officers have interests in the Merger that are different from yours and that may influence them to support or approve the Merger without regard to your interests.

Directors and executive officers of VYNE and Yarrow have interests in the Merger that are different from, or in addition to, the interests of other VYNE stockholders generally. These interests with respect to VYNE’s directors and executive officers may include, among others, retention bonus payments, acceleration of previously issued equity awards, severance payments if employment is terminated in a qualifying termination in connection with the Merger and rights to continued indemnification, expense advancement and insurance coverage.

Further, certain current members of the Yarrow board of directors will continue as directors of the Combined Company after the effective time, and, following the closing of the Merger, will be eligible to be compensated as non-employee directors of the Combined Company pursuant to VYNE’s non-employee director compensation policy that is expected to remain in place following the effective time. These interests, among other factors, may have influenced the directors and executive officers of each company to support or approve the Merger.

The VYNE board of directors was aware of and considered those interests, among other matters, in reaching their decisions to approve and adopt the Merger Agreement, approve the Merger, and recommend the approval of the Merger Agreement to VYNE and Yarrow stockholders. These interests, among other factors, may have influenced the directors and executive officers of each company to support or approve the Merger.

VYNE stockholders and Yarrow stockholders may not realize a benefit from the Merger commensurate with the ownership dilution they will experience in connection with the Merger, including the conversion of Yarrow Common Stock issued in the Yarrow Pre-Closing Financing.

If the Combined Company is unable to realize the full strategic and financial benefits currently anticipated from the Merger, VYNE stockholders and Yarrow stockholders will have experienced substantial dilution of their ownership interests without receiving any commensurate benefit, or only receiving part of the commensurate benefit to the extent the Combined Company is able to realize only part of the strategic and financial benefits currently anticipated from the Merger.

VYNE securityholders will generally have a reduced ownership and voting interest in, and will exercise less influence over the management of, the Combined Company following the completion of the Merger as compared to their current ownership and voting interests in the respective companies.

After the completion of the Merger, VYNE’s current stockholders will generally own a smaller percentage of the Combined Company than their ownership of VYNE prior to the Merger. Immediately after the Merger, VYNE securityholders as of immediately prior to the Merger are expected to own approximately 3.0% of the outstanding shares of capital stock of the Combined Company (on a fully-diluted basis, and subject to dilution from any equity issued by Yarrow after December 17, 2025 and before the closing), and former holders of Yarrow securities are expected to own approximately 97.0% of the outstanding shares of capital stock of the Combined Company (on a fully-diluted basis), subject to certain assumptions, including, but not limited to, VYNE’s net cash as of closing being approximately $0, after giving effect to the Cash Dividend, which is expected to be approximately $14.5 to $16.5 million. The Chief Executive Officer of Yarrow will serve as the Chief Executive Officer of the Combined Company following the completion of the Merger.

Certain provisions of the Merger Agreement may discourage third parties from submitting competing proposals, including proposals that may be superior to the transactions contemplated by the Merger Agreement.

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While the Merger Agreement is in effect, each party is generally prohibited from, among other things, soliciting, initiating or knowingly encouraging, inducing or facilitating the communication, making, submission or announcement of any acquisition proposal or acquisition inquiry. In addition, VYNE’s current directors and executive officers and certain significant stockholders have entered into support agreements pursuant to the terms of the Merger Agreement, and as an inducement to Yarrow’s willingness to enter into the Merger Agreement, by which they have agreed to vote all of their shares of VYNE capital stock in favor of the Merger Agreement and the transactions contemplated thereby and against any competing proposals, subject to certain limited exceptions. These provisions could discourage a potential competing acquirer from considering or proposing an acquisition or merger, even if it were prepared to pay consideration with a higher value than that implied by the merger consideration in the combination.

Because the lack of a public market for Yarrow Common Stock makes it difficult to evaluate the fair market value of its capital stock, the value of VYNE Common Stock to be issued to Yarrow stockholders may be more or less than the fair market value of Yarrow Common Stock.

The outstanding capital stock of Yarrow is privately held and is not traded on any public market. The lack of a public market makes it difficult to determine the fair market value of Yarrow capital stock. Because the percentage of VYNE’s equity to be issued to Yarrow stockholders was determined based on negotiations between the parties, it is possible that the value of VYNE Common Stock to be issued to Yarrow stockholders will be more or less than the fair market value of Yarrow Capital Stock.

Lawsuits may be filed against VYNE, Yarrow, or any of the members of their respective boards of directors arising out of the Merger, which may delay or prevent the Merger.

Putative stockholder complaints, including stockholder class action complaints, and other complaints may be filed against VYNE, the VYNE board of directors, Yarrow, the Yarrow board of directors and others in connection with the transactions contemplated by the Merger Agreement. The outcome of litigation is uncertain, and VYNE or Yarrow may not be successful in defending against any such future claims. Lawsuits that may be filed against VYNE, the VYNE board of directors, Yarrow, or the Yarrow board of directors could delay or prevent the Merger, divert the attention of VYNE’s and Yarrow’s management and employees from their day-to-day business and otherwise adversely affect VYNE and Yarrow financially.

VYNE has never paid and, other than in connection with the Merger with Yarrow, does not intend to pay any cash dividends in the foreseeable future.

VYNE has never paid cash dividends on any of its capital stock. Other than in connection with the Merger, VYNE does not currently anticipate declaring or paying cash dividends on its capital stock in the foreseeable future.

If VYNE does not successfully consummate the Merger or another strategic transaction, the VYNE board of directors may decide to pursue a dissolution and liquidation of VYNE. In such an event, the amount of cash available for distribution to VYNE stockholders will depend heavily on the timing of such liquidation as well as the amount of cash that will need to be reserved for commitments and contingent liabilities, as to which VYNE can give you no assurance.

There can be no assurance that the Merger will be completed. If the Merger is not completed, the VYNE board of directors may decide to pursue a dissolution and liquidation of VYNE. In such an event, the amount of cash available for distribution to VYNE stockholders will depend heavily on the timing of such decision and, ultimately, such liquidation, since the amount of cash available for distribution continues to decrease as VYNE funds its operations while pursuing the Merger. In addition, if the VYNE board of directors were to approve and recommend, and VYNE stockholders were to approve, a dissolution and liquidation of VYNE, VYNE would be required under Delaware law to pay VYNE’s outstanding obligations, as well as to make reasonable provision for contingent and unknown obligations, prior to making any distributions in liquidation to stockholders. VYNE’s commitments and contingent liabilities may include obligations under VYNE’s employment and related agreements with certain employees that provide for severance and other payments following a termination of employment occurring for various reasons, including a change in control of VYNE, litigation against VYNE, and other various claims and legal actions arising in the ordinary course of business, and other unexpected and/or contingent liabilities. As a result of this requirement, a portion of VYNE’s assets would need to be reserved pending the resolution of such obligations.

In addition, VYNE may be subject to litigation or other claims related to a dissolution and liquidation of VYNE. If a dissolution and liquidation were to be pursued, the VYNE board of directors, in consultation with VYNE’s advisors, would need to evaluate these matters and make a determination about a reasonable amount to reserve. Accordingly, holders of VYNE Common Stock could lose all

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or a significant portion of their investment in the event of liquidation, dissolution or winding up of VYNE. A liquidation would be a lengthy and uncertain process with no assurance of any value ever being returned to VYNE stockholders.

VYNE and its stockholders will not have any right to make damage claims against Yarrow for the breach of any representation, warranty or covenant made by Yarrow in the Merger Agreement.

The Merger Agreement provides that all of the representations, warranties and covenants of the parties contained therein shall not survive the closing of the Merger, except for those covenants contained therein that by their terms apply or are to be performed in whole or in part after the Closing, and then only with respect to breaches occurring after the closing of the Merger. Accordingly, there are no remedies available to the parties with respect to any breach of the representations, warranties, covenants or agreements of the parties to the Merger Agreement after the Closing of the Merger, except for covenants to be performed in whole or in part after the Closing. As a result, VYNE and its stockholders will have no remedy available to it if the Merger is consummated and it is later revealed that there was a breach of any of the representations, warranties and covenants made by Yarrow at the time of the Merger.

Additionally, VYNE cannot assure you that the due diligence conducted in relation to Yarrow has identified all material issues or risks associated with Yarrow, its business or the industry in which it competes. Furthermore, VYNE cannot assure you that factors outside of its or Yarrow’s control will not later arise, or that any previously identified risks will not materialize in a manner inconsistent with the preliminary analysis. As a result of these factors, following the closing of the Merger, the Combined Company may be exposed to liabilities and incur additional costs and expenses and it may be forced to later write-down or write off assets, restructure its operations, or incur impairment or other charges. VYNE and its stockholders have no indemnification rights against Yarrow or its stockholders under the Merger Agreement. Accordingly, any stockholders of VYNE that remain stockholders of the Combined Company following the Merger could suffer a reduction in the value of their securities. Such stockholders are unlikely to have a remedy for such reduction in value unless they are able to successfully claim that the reduction was due to the breach by VYNE’s directors or officers of a duty of care or other fiduciary duty owed to them, or if they are able to successfully bring a private claim under securities laws that the registration statement or proxy statement/prospectus relating to the Merger contained an actionable material misstatement or material omission.

Risks Related to the Proposed Reverse Stock Split

The reverse stock split may not increase the Combined Company’s stock price over the long-term.

The principal purpose of the reverse stock split is to increase the per-share market price of VYNE Common Stock above the minimum bid price requirement under the Nasdaq rules so that the listing of VYNE and the shares of VYNE Common Stock being issued in the Merger on Nasdaq will be approved. Based on the recent trading prices of VYNE Common Stock, VYNE and Yarrow currently estimate that a reverse stock split ratio of at least 1-for-     would be required to increase the per-share market price to $4.00, which is the minimum initial listing price requirement of Nasdaq. The final reverse stock split ratio will be determined mutually by the VYNE board of directors and the Yarrow board of directors prior to the closing of the Merger based primarily on the then-current trading price of VYNE Common Stock and the objective of achieving a post-closing per-share price that (1) satisfies Nasdaq’s listing requirements and (2) provides an appropriate and sustainable post-closing per-share market price that the parties believe will better position the Combined Company for long-term trading stability, investor interest and market visibility, taking into account prevailing market conditions and other relevant factors. Accordingly, the ratio effected is likely to be greater than the minimum necessary to satisfy Nasdaq’s listing standards. It cannot be assured, however, that the reverse stock split will accomplish this objective for any meaningful period of time. While it is expected that the reduction in the number of outstanding shares of common stock will proportionally increase the market price of VYNE Common Stock, it cannot be assured that the reverse stock split will increase the market price of its common stock by a multiple of the reverse stock split ratio mutually agreed by VYNE and Yarrow, or result in any permanent or sustained increase in the market price of VYNE Common Stock, which is dependent upon many factors, including VYNE’s business and financial performance, general market conditions and prospects for future success. Thus, while the stock price of VYNE might meet the listing requirements for Nasdaq initially, it cannot be assured that it will continue to do so.

The reverse stock split may decrease the liquidity of the Combined Company common stock.

Although the VYNE board of directors believes that the anticipated increase in the market price of the Combined Company common stock resulting from the proposed reverse stock split could encourage interest in its common stock and possibly promote greater liquidity for its stockholders, such liquidity could also be adversely affected by the reduced number of shares outstanding after the reverse stock split. The reduction in the number of outstanding shares may lead to reduced trading and a smaller number of market

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makers for the Combined Company common stock. In addition, the reverse stock split may not result in an increase in the Combined Company’s stock price necessary to satisfy Nasdaq’s initial listing requirements for the Combined Company.

The reverse stock split may lead to a decrease in the Combined Company’s overall market capitalization.

Should the market price of the Combined Company common stock decline after the reverse stock split, the percentage decline may be greater, due to the smaller number of shares outstanding, than it would have been prior to the reverse stock split. A reverse stock split is often viewed negatively by the market and, consequently, can lead to a decrease in the Combined Company’s overall market capitalization. If the per share market price does not increase in proportion to the reverse stock split ratio, then the value of the Combined Company, as measured by its stock capitalization, will be reduced. In some cases, the per-share stock price of companies that have effected reverse stock splits subsequently declined back to pre-reverse split levels, and accordingly, it cannot be assured that the total market value of the Combined Company common stock will remain the same after the reverse stock split is effected, or that the reverse stock split will not have an adverse effect on the Combined Company’s stock price due to the reduced number of shares outstanding after the reverse stock split.

Risks Related to VYNE

Risks Related to Development of VYNE’s Current Product Candidates

VYNE has been and, if the Merger is not consummated, is expected to be substantially dependent upon the successful development and regulatory approval of its biopharmaceutical product candidates. If VYNE is unable to successfully develop or obtain regulatory approval for any such candidate, its business may be materially harmed.

VYNE currently has no products approved for sale and has historically invested substantially all of its efforts and financial resources in the development of its BET inhibitor product candidates, repibresib gel (“rebipresib” or “VYN201”) and VYN202. If the Merger is not consummated, the identification, successful development and ultimate regulatory approval of a product candidate for any potential indications will be critical to the future success of VYNE’s business. VYNE would need to raise sufficient funds for, and successfully enroll and complete, clinical development for a product candidate.

VYNE’s ability to successfully progress any product candidate may be hampered for many reasons, including:

The development of these new chemical entities carries even greater risk and a higher probability of failure. VYNE’s failure to successfully develop VYNE’s product candidates will have a material adverse effect on VYNE’s business and financial condition.

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VYNE’s current product candidates may fail in development or suffer delays that materially and adversely affect their viability. If the Merger is not consummated and if VYNE is unable to complete development of, or commercialize, its product candidates, or experience significant delays in doing so, VYNE’s business will be materially harmed.

VYNE’s ability to achieve and sustain profitability depends on developing and obtaining regulatory approvals for, and successfully commercializing, VYNE’s product candidates, either alone or with third parties, and VYNE cannot guarantee you that it will ever obtain regulatory approval for any of VYNE’s product candidates. VYNE has limited experience in conducting and managing the clinical trials necessary to obtain regulatory approvals including approval by the FDA. Before obtaining regulatory approval for the commercial distribution of VYNE’s product candidates, VYNE or an existing or future collaborator must conduct extensive preclinical tests and clinical trials to demonstrate the safety and efficacy in humans of VYNE’s product candidates.

VYNE may not have the resources to advance the development of its product candidates if it experiences issues that delay or prevent their regulatory approval, or VYNE’s ability to commercialize them, including:

For example, in July 2025 VYNE announced topline results from its Phase 2b trial evaluating repibresib gel in nonsegmental vitiligo which did not meet its primary endpoint of the proportion of subjects achieving an improvement in Facial Vitiligo Area Scoring Index of at least 50% from baseline (“F-VASI50”) at week 24 compared to vehicle. The trial also missed a key secondary endpoint of F-VASI75. Based on these data, VYNE discontinued treatment in the then ongoing extension phase of the trial and terminated the trial.

VYNE’s inability to advance or complete the development of its product candidates, or significant delays in doing so, could have a material and adverse effect on VYNE’s business, financial condition, results of operations and prospects.

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If the Merger is not consummated and VYNE continues to develop its current product candidates or any future product candidates, VYNE may encounter delays in enrolling patients and successfully completing clinical trials for VYNE’s product candidates and may be delayed in, or prevented from, commencing or completing such trials due to factors that are largely beyond VYNE’s control.

VYNE has in the past experienced and may in the future experience delays in completing clinical trials and in commencing future clinical trials. Clinical trials can be delayed or terminated for a variety of reasons, including delay or failure to:

Patient enrollment is also a significant factor in the timing of clinical trials, or VYNE may be prevented from completing its clinical trials, and is affected by many factors, including the size and nature of the patient population, the proximity of patients to clinical sites, the eligibility criteria for the trial, the design of the clinical trial, competing clinical trials and clinicians’ and patients’ perceptions as to the potential advantages of the drug being studied in relation to available alternatives, including any new drugs or treatments that may be approved for the indications VYNE is investigating.

VYNE may be delayed in commencing or conducting its clinical trials, or VYNE may be prevented from completing its clinical trials, if the FDA, or other applicable regulatory authority, finds deficiencies or requests additional information with respect to VYNE’s Investigational New Drug Applications (“IND”).

For example, the FDA informed VYNE in April 2025 that it placed a clinical hold on VYNE’s Phase 1b trial for VYN202 following a recent observation of testicular toxicity in dogs from a non-clinical toxicology study with VYN202. The FDA lifted the clinical hold for female subjects on the 0.25 mg and 0.5 mg doses but did not lift the hold for subjects on the 1 mg dose due to its lower toxicological safety margin, even though a No-Observed-Adverse-Effect Level (“NOAEL”) was established covering all clinical doses in females. The FDA also required sufficient data from a 12-week non-clinical toxicology study of VYN202 in dogs in order to resume the trial in male clinical subjects. In addition to this dog study, VYNE may be required to conduct additional nonclinical studies in order to address the clinical hold, or initiate a new clinical study in the different indication, and if unsuccessful, VYNE may be unable to initiate a new clinical trial of VYN202 or such toxicity would limit the populations and indications for which VYN202 could be developed. These factors could lead to VYNE’s inability to further develop VYN202. VYNE may also encounter delays if a clinical trial or a clinical trial site is suspended or terminated by it, the IRB of the institutions in which such trials are being conducted, the trial’s data safety monitoring board, or the FDA. Such authorities may suspend or terminate one or more of VYNE’s clinical trials due to a number of factors, including VYNE’s failure to conduct the clinical trial in accordance with relevant regulatory requirements or clinical protocols, inspection of the clinical trial operations or trial site by the FDA resulting in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, failure to demonstrate a benefit from using a drug, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial.

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If VYNE experiences delays in carrying out or completing any clinical trial of its product candidates, VYNE may be forced to cease developing VYNE’s product candidates, VYNE may not be able to achieve approval of its product candidates and the commercial prospects of VYNE’s product candidates may be harmed. In addition, any delays in completing VYNE’s clinical trials, or inability to complete such trials, will increase VYNE’s costs, slow down VYNE’s product candidate development and approval process and jeopardize VYNE’s ability to commence product sales and generate revenues. Any of these occurrences may significantly harm VYNE’s business and financial condition. In addition, many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials may also ultimately lead to the denial of regulatory approval of VYNE’s product candidates.

International trade policies, including tariffs, sanctions and trade barriers, may adversely affect VYNE’s business, financial condition, results of operations and prospects.

VYNE operates in a global economy, which includes utilizing third-party suppliers in several countries outside the United States. There is inherent risk, based on the complex relationships among the U.S. and the countries in which VYNE conducts VYNE’s business, that political, diplomatic and national security factors can lead to global trade restrictions and changes in trade policies and export regulations that may adversely affect VYNE’s business and operations. The current international trade and regulatory environment is subject to significant ongoing uncertainty. The U.S. government has recently announced substantial new tariffs affecting a wide range of products and jurisdictions and has indicated an intention to continue developing new trade policies, including with respect to the pharmaceutical industry. In response, certain foreign governments have announced or implemented retaliatory tariffs and other protectionist measures. These developments have created a dynamic and unpredictable trade landscape, which may adversely impact VYNE’s business, results of operations, financial condition and prospects. The Bureau of Industry and Security, U.S. Department of Commerce, has initiated an investigation to determine whether pharmaceutical ingredients, including finished drug product, manufactured outside the United States pose a national security risk and should be subject to additional tariffs.

VYNE does not own or operate, and currently has no plans to establish, any manufacturing facilities. VYNE currently contracts with third party manufacturers for all of VYNE’s required raw materials, active ingredients and finished products for VYNE’s preclinical studies and clinical trials for VYNE’s product candidates. VYNE currently has no plans to establish VYNE’s own manufacturing capabilities and plans to continue to rely on third-party manufacturers for any future trials of VYNE’s product candidates. Currently, VYNE’s active pharmaceutical ingredients (“APIs”) for VYNE’s product candidates are manufactured in China. VYNE also relies on specialized laboratory equipment, supplies and materials, all or part of which VYNE believes may be ultimately sourced from multiple countries outside the United States, to advance VYNE’s research and development efforts.

Current or future tariffs may result in increased research and development expenses, including with respect to increased costs associated with APIs, raw materials, laboratory equipment and research materials and components. In addition, such tariffs will increase VYNE’s supply chain complexity and could also potentially disrupt VYNE’s existing supply chain. Unlike consumer goods, pharmaceuticals face unique regulatory constraints that make rapid supply chain adjustments particularly difficult and costly. Trade restrictions affecting the import of materials necessary for clinical trials could result in delays to VYNE’s development timelines. Increased development costs and extended development timelines could place VYNE at a competitive disadvantage compared to companies operating in regions with more favorable trade relationships and could reduce investor confidence, negatively impacting VYNE’s ability to secure additional financing on favorable terms or at all.

Foreign governments may also take other retaliatory actions against U.S. entities, such as decreased intellectual property protection, increased enforcement actions, or delays in regulatory approvals, which may result in heightened international legal and operational risks. In addition, the United States and other governments have imposed and may continue to impose additional sanctions, such as trade restrictions or trade barriers, which could restrict us from doing business directly or indirectly in or with certain countries or parties and may impose additional costs and complexity to VYNE’s business.

Trade disputes, tariffs, restrictions and other political tensions between the United States and other countries may also exacerbate unfavorable macroeconomic conditions including inflationary pressures, foreign exchange volatility, financial market instability and economic recessions or downturns. The ultimate impact of current or future tariffs and trade restrictions remains uncertain and could materially and adversely affect VYNE’s business, financial condition and prospects. While VYNE actively monitors these risks, any prolonged economic downturn, escalation in trade tensions, or deterioration in international perception of U.S.-based companies could materially and adversely affect VYNE’s business, ability to access the capital markets or other financing sources, results of operations, financial condition and prospects. In addition, tariffs and other trade developments have and may continue to heighten the risks related to the other risk factors described elsewhere in this proxy statement/prospectus.

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Drug development is very expensive, time-consuming and uncertain. VYNE’s preclinical studies and clinical trials may fail to adequately demonstrate the safety and efficacy of VYNE’s current or any future product candidates, or serious adverse side effects could be identified. Any of these outcomes could prevent or delay regulatory approval and commercialization or, if the Merger is not consummated, harm VYNE’s ability to pursue other strategic alternatives for VYNE’s product candidates.

Drug development is very expensive, time-consuming and difficult to design and implement, and its outcome is inherently uncertain, particularly as it relates to new chemical entities. Before obtaining regulatory approval for the commercial sale of a product candidate, VYNE must demonstrate through preclinical studies and clinical trials that a product candidate is both safe and effective for use in the target indication. Most product candidates that commence clinical trials are never approved by regulatory authorities for commercialization. The clinical trials for these product candidates may take significantly longer than expected to complete. In addition, VYNE, any partner with which it may in the future collaborate, the FDA, an IRB or other regulatory authorities, including state and local agencies and counterpart agencies in foreign countries, may prevent, suspend, delay, require modifications to or terminate VYNE’s clinical trials at any time, for various reasons, including:

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If VYNE experiences delays in the completion of, or if it terminates, any of its future clinical trials, VYNE’s business, financial condition, operating results and prospects would be adversely affected.

In addition, product candidates that initially showed promise in early stage testing may later be found to be not effective or cause side effects that prevent further development of the product candidate. For example, on July 30, 2025, VYNE announced that VYNE’s Phase 2b trial of repibresib gel in nonsegmental vitiligo did not achieve primary endpoint or key secondary endpoint of F-VASI50 and F-VASI75, respectively. VYNE also announced in July 2025 that VYNE decided to discontinue treatment in the ongoing extension phase of the trial and terminated the trial. If VYNE’s product candidates are associated with side effects in preclinical studies and/or clinical trials or have characteristics that are unexpected, a number of potentially significant negative consequences could result, including:

Any of these events could prevent VYNE from pursuing strategic alternatives, including identifying and consummating transactions with third-party partners, to further develop, obtain marketing approval for and/or commercialize the particular product candidate and could significantly harm VYNE’s business, results of operations and prospects.

New chemical entities may require more time and resources for development, testing and regulatory approval.

Each of VYNE’s historical BET inhibitor programs involves a novel therapeutic approach and new chemical entity, requires significant further research and development and regulatory approvals and is subject to the risks of failure inherent in the development of products based on innovative approaches. New chemical entities derived from VYNE’s InhiBET platform are molecules that have not previously been approved and marketed as therapeutics. As a result, the product candidates from VYNE’s InhiBET platform may face greater risk of unanticipated safety issues or other side-effects, or may not demonstrate efficacy. For example, systemic BET inhibitors have historically targeted both BD1 and BD2 less selectively, causing gastrointestinal toxicity and bone marrow suppressive effects like thrombocytopenia. While VYNE believes VYN202’s high selectivity for BD2 may alleviate the therapeutic limiting toxicities observed by other less BD2-selective BET inhibitors, VYNE may need to spend more time and greater resources verifying any toxicity associated with VYN202, including the 12 week canine toxicology study that VYNE is currently conducting in order to permit future dosing of male patients. Accordingly, the regulatory pathway for VYNE’s new chemical entities may be more demanding and take a longer period of time.

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Results obtained in preclinical studies and completed clinical trials may not predict success in later clinical trials.

Success in preclinical testing and early clinical trials does not ensure that later clinical trials will be successful, and any future clinical trials that VYNE may conduct may not demonstrate consistent or adequate efficacy and safety to obtain regulatory approval to market VYNE’s product candidates in any indication. Companies in the biopharmaceutical industry frequently suffer significant setbacks in later-stage clinical trials, even after achieving promising results in preclinical studies or earlier clinical trials. Phase 3 clinical trials often produce unsatisfactory results even though prior clinical trials were successful. For example, VYNE’s Phase 2b trial of repibresib gel in nonsegmental vitiligo did not meet its primary or secondary endpoint, and VYNE’s VYN202 Phase 1b trial in moderate to severe plaque psoriasis was terminated early due to the need to conduct a canine 12 week nonclinical study in order to reinitiate dosing in male patients. Any such future events could prevent VYNE from pursuing strategic alternatives, including identifying and consummating transactions with third-party partners, to further develop, obtain marketing approval for and/or commercialize a particular product candidate and could significantly harm VYNE’s business, results of operations and prospects.

Top-line and preliminary data from VYNE’s clinical trials that it announces or publishes from time to time may change as additional data become available and are subject to audit and verification procedures that could result in material changes in the final data.

VYNE may publicly disclose top-line or preliminary data from its clinical trials based on a preliminary analysis of then-available data. In that case, the results and related findings and conclusions remain subject to change following a complete analysis of all data related to the trial. VYNE also makes certain assumptions, estimations, calculations and conclusions as part of its analyses of data, and it may not have received or had the opportunity to fully and carefully evaluate all data. As a result, the top-line or preliminary results that VYNE reports may differ from future results of the same trials, or different conclusions or considerations may qualify such results, once additional data have been received and fully evaluated. Top-line data also remain subject to audit and verification procedures that may result in the final data being materially different from the preliminary data VYNE previously published. Accordingly, top-line and preliminary data should not be considered complete and should be viewed with caution until the final data are available. VYNE may also disclose interim data from its clinical trials. Interim data from clinical trials that VYNE may complete are subject to the risk that one or more of the clinical outcomes may materially change as subject enrollment continues and more subject data become available. Adverse differences between interim, top-line or preliminary data and final data could significantly harm VYNE’s reputation and business prospects. Further, disclosure of interim, top-line or preliminary data by VYNE or by its competitors could result in volatility in the price of VYNE Common Stock.

Further, others, including regulatory agencies, may not accept or agree with VYNE’s assumptions, estimates, calculations, conclusions or analyses or may interpret or weigh the importance of data differently, which could impact the potential of the particular program, the likelihood of marketing approval or commercialization of the particular product candidate, any approved product, and VYNE’s company in general. In addition, the information VYNE chooses to publicly disclose regarding a particular study or clinical trial is derived from information that is typically extensive, and you or others may not agree with what VYNE determines is material or otherwise appropriate information to include in VYNE’s disclosure, and any information VYNE determines not to disclose may ultimately be deemed significant with respect to future decisions, conclusions, views, activities or otherwise regarding a particular program, product candidate or VYNE’s business.

If the interim, top-line or preliminary data that VYNE reports differ from actual results, or if others, including regulatory authorities, disagree with the conclusions reached, VYNE’s ability to pursue strategic alternatives, including identifying and consummating transactions with third-party partners to further develop, obtain marketing approval for and/or commercialize its product candidates may be harmed, which could harm VYNE’s business, operating results, prospects or financial condition.

VYNE has a limited history as a clinical-stage biopharmaceutical company developing product candidates for immuno-inflammatory conditions, which may make it difficult to assess VYNE’s future viability.

VYNE’s team has limited experience in developing drugs for the treatment of immuno-inflammatory conditions. Consequently, any predictions you make about VYNE’s future success or viability may not be as accurate as they could be if VYNE had a longer history of being a clinical-stage biopharmaceutical company focused on developing drugs in this area. VYNE may also encounter unforeseen expenses, difficulties, complications, delays and other known or unknown factors in achieving its business objectives.

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If the Merger is not consummated and VYNE does not complete an alternative strategic transaction, VYNE may spend its limited resources to pursue another product candidate or indication and fail to capitalize on product candidates or indications that may be more profitable or for which there is a greater likelihood of success.

VYNE may forego or delay pursuit of opportunities with other product candidates or for other indications that later prove to have greater commercial potential. VYNE’s resource allocation decisions may cause it to fail to capitalize on viable commercial drugs or profitable market opportunities. VYNE’s spending on current and future development programs and product candidates for specific indications may not yield any commercially viable drugs. If VYNE does not accurately evaluate the commercial potential or target market for a particular product candidate, it may relinquish valuable rights to that product candidate through partnerships, licensing or other arrangements in cases in which it would have been more advantageous for VYNE to retain sole development and commercialization rights to such product candidate.

VYNE faces competition from entities that have developed or may develop product candidates for the diseases addressed by VYNE’s product candidates, including companies developing novel treatments and technology platforms. If these companies develop technologies or product candidates more rapidly than VYNE does or their technologies are more effective, VYNE’s ability to develop and successfully commercialize product candidates may be adversely affected.

The development and commercialization of drugs is extremely competitive. VYNE’s product candidates, if approved, will face significant competition and VYNE’s failure to effectively compete may prevent it from achieving significant market penetration. Most of VYNE’s competitors have significantly greater resources than VYNE does, and VYNE may not be able to successfully compete. VYNE competes with a variety of multinational biopharmaceutical companies, specialized biotechnology companies and emerging biotechnology companies, as well as with technologies and product candidates being developed at universities and other research institutions. VYNE’s competitors have developed, are developing or will develop product candidates and processes competitive with VYNE’s product candidates and processes. Competitive therapeutic treatments include those that have already been approved and accepted by the medical community and any new treatments, including those based on novel technology platforms that enter the market. VYNE believes that a significant number of products are currently under development, and may become commercially available in the future, for the treatment of conditions for which VYNE is trying, or may try, to develop product candidates. There is intense and rapidly evolving competition in the biotechnology and biopharmaceutical fields. Competition from many sources exists or may arise in the future. VYNE’s competitors include larger and better funded biopharmaceutical, biotechnological and therapeutics companies, including companies focused on therapeutics for autoimmune diseases. Moreover, VYNE also competes with current and future therapeutics developed at universities and other research institutions. Some of these companies are well-capitalized and, in contrast to VYNE, have significant clinical experience, and may include VYNE’s existing or future collaborators. In addition, these companies compete with VYNE in recruiting scientific and managerial talent. VYNE’s success will depend partially on its ability to develop and commercialize therapeutics that are safer and more effective than competing therapeutics. VYNE’s commercial opportunity and success will be reduced or eliminated if competing therapeutics are safer, more effective, or less expensive than the therapeutics it develops.

VYNE has not obtained regulatory approvals to market its product candidates, and if the Merger is not consummated or VYNE does not complete another strategic transaction, VYNE may continue to develop its own product candidates and may be delayed in obtaining or fail to obtain such regulatory approvals and to commercialize these product candidates.

The process of developing, obtaining regulatory approval for and commercializing VYNE’s product candidates is long, complex, costly and uncertain, and delays or failure can occur at any stage. Furthermore, the research, testing, manufacturing, labeling, marketing, sale and distribution of drugs are subject to extensive and rigorous regulation by the FDA. VYNE is not permitted to market any of its product candidates in the United States until it receives approval of the applicable New Drug Application (“NDA”) from the FDA. To gain approval of an NDA or other equivalent regulatory approval, VYNE must provide the FDA with clinical data and other information that demonstrates the continued safety and efficacy of the product for the intended indication.

Even if VYNE believes it clinical trials were successful, the FDA may require that VYNE conduct additional clinical, nonclinical, manufacturing, validation or drug product quality studies and submit that data before considering or reconsidering any NDA VYNE may submit. Depending on the extent of these additional studies, approval of any applications that VYNE submits may be significantly delayed or may require it to expend more resources than it has available. It is also possible that additional studies VYNE conducts may not be considered sufficient by the FDA to provide regulatory approval.

If any of these outcomes occur, VYNE would not receive approval for its product candidates and may need to discontinue the development of such product candidates.

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Even if VYNE’s product candidates receive marketing approval, VYNE may continue to face future developmental and regulatory difficulties. In addition, VYNE is subject to government regulations and VYNE may experience delays in obtaining required regulatory approvals to market VYNE’s proposed product candidates.

Even if VYNE receives approval of any regulatory filing for its product candidates, the FDA may grant approval contingent on the performance of additional costly post-approval clinical trials or risk evaluation and mitigation strategies (“REMS”) to monitor the safety or efficacy of the product, which could negatively impact VYNE by reducing revenues or increasing expenses, and cause the product not to be commercially viable. Absence of long-term safety data may further limit the approved uses of products.

The FDA may also approve VYNE’s product candidates for a more limited indication or a narrower patient population than VYNE originally requested, or may not approve the labeling that VYNE believes is necessary or desirable for the successful commercialization of its product candidates. Furthermore, any such approved product will remain subject to extensive regulatory requirements, including requirements relating to manufacturing, labeling, packaging, adverse event reporting, storage, advertising, promotion, distribution and recordkeeping.

If VYNE fails to comply with the regulatory requirements of the FDA, or if VYNE discovers previously unknown problems with any approved commercial products, manufacturers or manufacturing processes, VYNE could be subject to administrative or judicially imposed sanctions or other setbacks, which could require it to take corrective actions, including to:

In addition, various aspects of VYNE’s operations are subject to federal, state or local laws, rules and regulations, any of which may change from time to time. Costs arising out of any regulatory developments could be time-consuming and expensive and could divert management resources and attention and, consequently, could adversely affect VYNE’s business operations and financial performance.

VYNE has historically relied on third parties to conduct, supervise and monitor VYNE’s clinical trials, and if these third parties perform in an unsatisfactory manner, it may harm VYNE’s business.

VYNE has historically relied, and may in the future rely, on medical institutions, clinical investigators, contract laboratories, collaborative partners and other third parties, such as CROs, to assist it in conducting its clinical trials for its other product candidates. While VYNE has had, and expects to have, agreements governing their activities, VYNE will have limited influence over their actual performance. VYNE will control only certain aspects of VYNE’s CROs’ activities. Nevertheless, VYNE will be responsible for ensuring that each of VYNE’s clinical trials is conducted in accordance with the applicable protocol, legal, regulatory and scientific standards, and VYNE’s reliance on the CROs does not relieve VYNE of its regulatory responsibilities.

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VYNE and its and CROs are required to comply with the FDA’s and other regulatory authorities’ good clinical practices (“GCPs”) for conducting, recording and reporting the results of clinical trials to assure that the data and reported results are credible and accurate, and that the rights, integrity and confidentiality of clinical trial participants are protected. If VYNE or its CROs fail to comply with applicable GCPs, or if VYNE’s CROs do not adequately monitor the conduct of medical institutions, clinical investigators, contract laboratories or other third parties involved in VYNE’s clinical trials, the clinical data generated in VYNE’s clinical trials may be deemed unreliable and the FDA and other regulatory authorities may require VYNE to perform additional clinical trials before approving any marketing applications.

If the third parties or consultants that assist VYNE in conducting its clinical trials do not perform their contractual duties or obligations, experience work stoppages, do not meet expected deadlines, terminate their agreements with VYNE or need to be replaced, or if the quality or accuracy of the clinical data they obtain is compromised due to the failure to adhere to VYNE’s clinical trial protocols or GCPs, or for any other reason, VYNE’s clinical trial results may be negatively impacted and/or VYNE may need to conduct additional clinical trials or enter into new arrangements with alternative third parties, which could be difficult, costly or impossible. As a result, VYNE’s clinical trials may be extended, delayed or terminated or may need to be repeated. If any of the foregoing were to occur, VYNE may not be able to obtain, or may be delayed in obtaining, regulatory approval for the product candidates being tested in such trials, and will not be able to, or may be delayed in VYNE’s efforts to, successfully commercialize these product candidates.

Changes in methods of product candidate manufacturing or formulation may result in additional costs or delays.

As product candidates are developed through preclinical studies to later-stage clinical trials towards approval and commercialization, it is common that various aspects of the development program, such as manufacturing methods and formulation, are altered in an effort to optimize processes and results. For example, VYNE evaluated a gel formulation of repibresib in VYNE’s Phase 2b trial rather than an ointment, which was used in VYNE’s completed Phase 1b trial. Such modifications carry the risk that they will not achieve these intended objectives, and may also require additional testing, FDA notification or FDA approval. Any of these changes could cause VYNE’s product candidates to perform differently and affect the results of planned clinical trials or other future clinical trials conducted with the altered materials. This could delay completion of clinical trials, require the conduct of bridging clinical trials or the repetition of one or more clinical trials, increase clinical trial costs, delay approval of VYNE’s product candidates and jeopardize VYNE’s ability to pursue strategic alternatives, including identifying and consummating transactions with third-party partners to further develop, obtain marketing approval for and/or commercialize VYNE’s product candidates.

Risks Related to VYNE’s Financial Position and Need for Capital

VYNE will need substantial additional funding to pursue its business objectives if the Merger is not completed. If VYNE is unable to raise capital when needed, it could be forced to curtail its planned operations.

Identifying potential product candidates and conducting preclinical testing and clinical trials is a time- consuming, expensive and uncertain process that takes years to complete. VYNE may never generate the necessary data or results required to obtain marketing approval for and/or commercialize its product candidates or identify and consummate transactions with third-party partners to further develop its product candidates. VYNE expects to incur significant expenses and operating losses for the foreseeable future if its advances its product candidates from discovery through preclinical and clinical development. In addition, VYNE may not be able to identify and consummate transactions with third-party partners to further develop, obtain marketing approval for and/or commercialize its product candidates, and its product candidates, if approved, may not achieve commercial success. Furthermore, VYNE incurs and expects to continue to incur significant costs associated with operating as a public company, including legal, accounting, investor relations and other expenses.

As of December 31, 2025, VYNE had $29.0 million in cash, cash equivalents and marketable securities. Based on VYNE’s current operating plan, VYNE believes these resources will fund its operating and capital expenditure requirements through the anticipated closing date of the Merger, which is subject to approval by its stockholders and the stockholders of Yarrow and other customary closing conditions, and for a period of at least 12 months from the date of issuance of the audited consolidated financial statements of VYNE appearing elsewhere in this proxy statement/prospectus.

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These assumptions may prove to be wrong, however, and VYNE could use its available capital resources sooner than is expects. Changes may occur beyond VYNE’s control that would cause it to consume its available capital before that time, including changes in and progress of VYNE’s development activities, acquisitions of additional products or product candidates, and changes in regulation.

Additional capital may not be available when VYNE needs it, on terms that are acceptable to it or at all. If adequate funds are not available to VYNE on a timely basis, it may be required to revise its operating plan in order to:

If VYNE raises additional capital through collaborations, strategic alliances or licensing arrangements with third parties, it may have to relinquish certain valuable rights to its product candidates, technologies, future revenue streams or research programs or grant licenses on terms that may not be favorable to VYNE. If VYNE raises additional capital through public or private equity offerings, the ownership interest of VYNE’s existing stockholders will be diluted and the terms of any new debt securities or equity securities may have a preference over VYNE Common Stock. In addition, if VYNE issues warrants or preferred stock in connection with its financing activities, such securities may include terms that are unfavorable to VYNE’s stockholders, including anti-dilution provisions and other preferences. In addition, any holders of preferred stock may receive preferential voting rights that are superior to the voting rights of holders of VYNE Common Stock. If VYNE raises additional capital through debt financing, it may be subject to covenants limiting or restricting VYNE’s ability to take specific actions, such as incurring additional debt or making capital expenditures or specified financial ratios, any of which could restrict VYNE’s ability to operate its business.

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VYNE has incurred significant losses since its inception and it anticipates that it will continue to incur significant losses for the foreseeable future, which could harm VYNE’s future business prospects.

VYNE has historically incurred substantial net losses, including net losses of $26.5 million and $39.8 million for the years ended December 31, 2025 and 2024, respectively. As of December 31, 2025, VYNE had an accumulated deficit of $757.7 million. VYNE expects to continue to incur significant losses in connection with its ongoing activities, including continuing to operate as a public company. These losses have had, and will continue to have, an adverse effect on VYNE’s working capital, total assets, and shareholders’ equity. Because of the numerous risks and uncertainties associated with VYNE’s research and development, VYNE is unable to predict when it will become profitable, and it may never become profitable. Even if VYNE does achieve profitability, it may not be able to sustain or increase profitability on a quarterly or annual basis. VYNE’s inability to achieve and then maintain profitability would negatively affect VYNE’s business, financial condition, results of operations, and cash flows.

VYNE anticipates that its expenses will increase substantially if and as it:

VYNE’s expenses could increase beyond its expectations if it is required by the FDA or other regulatory authorities to perform clinical trials in addition to those that it currently expects.

SEC regulations limit the amount of funds VYNE can raise during any 12-month period pursuant to VYNE’s shelf registration statement on Form S-3.

SEC regulations limit the amount that companies with a public float of less than $75 million may raise during any 12-month period pursuant to a shelf registration statement on Form S-3, referred to as the baby shelf rules. As of the filing of this proxy statement/prospectus, VYNE is subject to such rules. Under these rules, the amount of funds VYNE can raise through primary public offerings of securities in any 12-month period using its registration statement on Form S-3, including its at-the-market equity offering program, will be limited to one-third of the aggregate market value of the shares of VYNE Common Stock held by VYNE’s non-affiliates. Therefore, VYNE will be significantly limited in the amount of proceeds it is able to raise by selling shares of VYNE Common Stock using its Form S-3 until such time as VYNE’s public float exceeds $75 million. Furthermore, if VYNE is required to file a new registration statement on another form, it may incur additional costs and be subject to delays due to review by the SEC staff.

Raising additional capital may cause dilution to VYNE’s stockholders, restrict VYNE’s operations or require it to relinquish proprietary rights.

If the Merger is not consummated, VYNE may finance its cash needs through a combination of equity offerings, debt financings, collaborations, strategic alliances and licensing arrangements. On March 1, 2024, VYNE entered into a sales agreement with Cowen and Company, LLC, as sales agent (“Cowen”) under which it may offer and sell, from time to time at its sole discretion, shares of VYNE Common Stock through Cowen in an at-the-market offering having an aggregate offering price up to $50.0 million. To the extent that VYNE raises additional capital through the sale of equity or convertible debt securities, your ownership interest will be diluted and the terms of these securities may include liquidation, anti-dilution protection or other preferences that adversely affect your rights as a stockholder. Debt financing, if available, may involve agreements that include covenants limiting or restricting

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VYNE’s ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends. In addition, VYNE may opportunistically seek additional capital due to favorable market conditions or strategic considerations, even if it believes that it has sufficient funds for VYNE’s current or future operating plans.

If VYNE raises additional funds through collaborations, strategic alliances or licensing arrangements with third parties, VYNE may have to relinquish valuable rights to its technologies, future revenue streams, research programs or product candidates or grant licenses on terms that may not be favorable to VYNE. If VYNE is otherwise unable to raise additional funds through equity or debt financings when needed, VYNE may be required to delay, reduce or terminate VYNE’s product development or grant rights to third parties to develop product candidates that it would otherwise prefer to develop itself.

Other Risks Related to VYNE’s Business and Financial Operations

Collaboration arrangements that VYNE may enter into in the future may not be successful, which could adversely affect VYNE’s ability to develop and commercialize VYNE’s product candidates.

Prior to the Merger or if the Merger is not consummated, VYNE may seek collaboration arrangements with pharmaceutical or biotechnology companies for the development or eventual commercialization of its product candidates in the future. Prior to the Merger or if the Merger is not consummated, VYNE may enter into arrangements on a selective basis, depending on the merits of retaining certain rights itself compared to entering into selective collaboration arrangements with pharmaceutical or biotechnology companies internationally and possibly also in the United States. Any such collaboration arrangements may not be successful.

In addition, the success of future collaboration arrangements that VYNE may enter into will depend heavily on the efforts and activities of VYNE’s collaborators. Collaborators generally have significant discretion in determining the efforts and resources that they will apply to these collaborations.

When entering collaboration arrangements, VYNE is subject to a number of risks, including:

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VYNE is subject to various risks and uncertainties arising out of the completed divestiture of its commercial business, any of which could materially and adversely affect VYNE’s business and operations, and VYNE’s stock price.

VYNE completed the sale of its prior commercial business in January 2022. Pursuant to the terms of the Asset Purchase Agreement entered into in connection with the purchase of that business by Journey Medical Corporation (“Journey”), VYNE is eligible to receive sales milestone payments of up to $450.0 million in the aggregate upon the achievement of specified levels of net sales on a product-by-product basis, beginning with annual net sales exceeding $100.0 million. In addition, VYNE is entitled to receive certain payments from any licensing or sublicensing of the assets by Journey outside of the United States. Under the terms of the agreement, Journey does not have any diligence obligations to achieve any such net sales milestones, and VYNE can provide no assurance that such milestones will ever be met. Furthermore, Journey may decide not to license or sublicense the assets in any territory outside of the United States, in which case VYNE would not receive any additional related payments. If any of the foregoing events occur, VYNE will not realize all of the benefits of the sale.

In addition, VYNE is still subject to potential liabilities relating to its historical commercial business operations that were subject to the Asset Purchase Agreement. Under the terms of the Asset Purchase Agreement, VYNE retained and is responsible for historical liabilities of the commercial business operations based on events occurring prior to the sale other than those liabilities expressly assumed by Journey. For example, VYNE remains liable for payment of product sales provisions, such as distribution fees and trade discounts and allowances, rebates, chargebacks and other discounts and product returns. See “Note 2 — Significant Accounting Policies — Revenue Recognition — Product Sales Provisions” in VYNE’s audited consolidated financial statements included in this proxy statement/prospectus. VYNE is also obligated to indemnify Journey against certain potential liabilities and for breaches of certain representations, warranties and covenants under the agreement up to certain caps, and those liabilities may be set off against any future payments owed to it by Journey. In addition to direct expenditures for damages, settlement and defense costs, there is the possibility of adverse publicity as a result of any such claims, any of which could have a material adverse effect on VYNE’s business and stock price. In addition, VYNE remains subject to potential investigation or inquiry by regulatory authorities with respect to VYNE’s legacy commercial business operations, which could result in additional distraction to VYNE’s management and could ultimately result in further liabilities.

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VYNE’s failure to successfully in-license, acquire, develop and market additional product candidates or approved products could impair its ability to grow its business.

If the Merger is not consummated, VYNE may pursue other strategic alternatives or in-license, acquire and develop additional product candidates. The success of this strategy depends partly upon VYNE’s ability to identify and select promising pharmaceutical product candidates, negotiate licensing or acquisition agreements with their current owners and finance these arrangements.

The process of proposing, negotiating and implementing a license or acquisition of a product candidate is lengthy and complex. Other companies, including some with substantially greater financial and other resources may compete with VYNE for the license or acquisition of product candidates. VYNE has limited resources to identify and execute the acquisition or in-licensing of third-party product candidates, businesses and technologies and integrate them into VYNE’s current infrastructure. Moreover, VYNE may devote resources to potential acquisitions or licensing opportunities that are never completed, or it may fail to realize the anticipated benefits of such efforts. Additionally, VYNE may not be able to acquire the rights to additional product candidates on terms that it finds acceptable, or at all.

Further, any product candidate that VYNE acquires may require additional development efforts prior to commercial sale, including preclinical or clinical testing and approval by the FDA and applicable foreign regulatory authorities. All product candidates are prone to risks of failure typical of pharmaceutical product development, including the possibility that a product candidate will not be shown to be sufficiently safe and effective for approval by regulatory authorities.

If the Merger is not consummated, VYNE may engage in strategic transactions, which could impact its liquidity, increase its expenses and present significant distractions to its management.

VYNE may in-license and acquire product candidates or engage in other strategic transactions if the Merger is not consummated. Additional potential transactions that VYNE may consider include a variety of different business arrangements, including out-licensing, strategic partnerships, joint ventures, restructurings, divestitures, business combinations and investments. Any such transaction may require VYNE to incur non-recurring or other charges, may increase VYNE’s near- and long-term expenditures and may pose significant integration challenges or disrupt VYNE’s management or business, which could adversely affect VYNE’s operations and financial results. For example, these transactions entail numerous potential operational and financial risks, including:

Accordingly, there can be no assurance that VYNE will undertake or successfully complete any transactions of the nature described above, and any transaction that it does complete could harm its business, financial condition, operating results and prospects.

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VYNE may decide not to continue developing any of its product candidates at any time during development or of any of its products after approval, which would reduce or eliminate VYNE’s potential return on investment for those product candidates or products.

VYNE has in the past decided and may again in the future decide to discontinue the development of any of its product candidates in its pipeline or not to continue to commercialize any approved product. For example, in July 2025 VYNE announced topline results from its Phase 2b trial evaluating repibresib gel in nonsegmental vitiligo which did not meet its primary endpoint of the proportion of subjects achieving an improvement in Facial Vitiligo Area Scoring Index of at least 50% from baseline (F-VASI50) at week 24 compared to vehicle. The trial also missed a key secondary endpoint of F-VASI75. Based on these data, VYNE discontinued treatment in the then ongoing extension phase of the trial and terminated the trial. VYNE may discontinue development of other product candidates for a variety of reasons, such as the appearance of new technologies that make its product less commercially viable, resource allocation management, an increase in competition from generic or other competing products, changes in or failure to comply with applicable regulatory requirements, the discovery of unforeseen side effects during clinical development or after the approved product has been marketed or the occurrence of adverse events at a rate or severity level that is greater than experienced in prior clinical trials. If VYNE discontinues a program in which VYNE has invested significant resources, VYNE will receive a limited return on its investment and VYNE will have missed the opportunity to have allocated those resources to other product candidates in its pipeline that may have had potentially more productive uses.

Supply interruptions may disrupt the availability of VYNE’s product candidates and cause delays in conducting preclinical or clinical activities.

VYNE has historically depended on a limited number of manufacturing facilities to manufacture its product candidates. Numerous factors could cause interruptions in the supply or manufacture of VYNE’s product candidates, including:

Furthermore, the primary manufacturer of the API in VYNE’s historical product candidates is WuXi Apptec, located in China. Certain Chinese biotechnology companies, including Wuxi Apptec, and contract manufacturing organizations (“CMOs”) may become subject to trade restrictions, sanctions, and other regulatory requirements by the U.S. government, which could restrict or even prohibit VYNE’s ability to work with such entities, thereby potentially disrupting the supply of material to VYNE. Such disruption could have adverse effects on the development of VYNE’s product candidates and VYNE’s business operations. The United States has recently passed legislation, namely the BIOSECURE Act (the “Act”), to prohibit U.S. federal executive agencies from procuring or obtaining any biotechnology equipment or service produced or provided by a “biotechnology company of concern” or entering into or renewing a contract, loan, or grant with an entity that uses such biotechnology equipment or equipment. The Act prohibits the U.S. Government from procuring or obtaining biotechnology equipment or services produced or provided by a “biotechnology company of concern” (“BCC”); entering into, extending, or renewing government contracts with an entity that directly or indirectly (e.g., via a subcontractor) uses biotechnology equipment or services from a BCC in performance of that federal contract; and/or issuing grants or loans to purchase, obtain, or use biotechnology equipment or services produced by a BCC. The Act also prohibits U.S. government loan and grant recipients from using federal loan or grant money to enter into contracts with entities that use equipment from BCCs in

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the performance of any federal prime contract or subcontract. Companies designated as a BCC include those that are identified on the U.S. Department of Defense’s annual List of Chinese Military Companies, also known as the 1260H List, and the U.S. Government also has the ability to designate entities as BCCs through a separate designation process. Given the Act, VYNE may be restricted in its ability to work with certain Chinese biotechnology companies to the extent it would contract with, or otherwise receive funding from, the U.S. government. As a result, VYNE may need to seek alternative suppliers. If VYNE is required to change manufacturers for any reason, it will be required to verify that the new manufacturer maintains facilities and procedures that comply with quality standards and with all applicable regulations and guidelines.

Production of product is necessary to perform preclinical activities and clinical trials and successful registration batches are necessary to file for approval to commercially market and sell product candidates. Delays in obtaining clinical material or registration batches could adversely impact VYNE’s clinical trials and delay regulatory approval for VYNE’s product candidates.

VYNE might not be able to utilize a significant portion of its net operating loss (“NOL”) carryforwards and research and development tax credit carryforwards.

As of December 31, 2025, VYNE had federal and state NOL carryforwards of $332.1 million and $94.2 million, respectively, of which $4.1 million will begin to expire in 2037 for federal and $94.2    million will begin to expire in 2040 for state purposes. As of December 31, 2025, VYNE had federal research and development tax credit carryforwards of $7.1million which will begin to expire in 2031. VYNE has no state research and development tax credit carryforwards. U.S. federal NOLs incurred in taxable years beginning after December 31, 2017 may be carried forward indefinitely, but the ability to utilize such federal NOL carryforwards to offset taxable income is limited to 80% of VYNE’s current year taxable income. In addition, under Sections 382 and 383 of the Internal Revenue Code of 1986, as amended, and corresponding provisions of state law, if a corporation undergoes an “ownership change” (generally defined as a greater than 50 percentage point change, by value, in its equity ownership by significant stockholders over a three-year period) the corporation’s ability to use its pre-change NOL carryforwards and other pre-change tax attributes to offset its post-change income or tax liability may be limited. The Merger will result in an ownership change for VYNE and, accordingly, its NOL carryforwards and certain other tax attributes will be subject to limitations (or disallowance) on their use after the Merger. Yarrow’s NOL carryforwards may also be subject to limitation as a result of prior shifts in equity ownership and/or the Merger. Additional ownership changes in the future could result in additional limitations on VYNE’s, Yarrow’s and the Combined Company’s NOL carryforwards. VYNE has not completed a Section 382 study through December 31, 2025; however, VYNE has completed a 382 study through March 31, 2025, and has determined that VYNE also experienced ownership changes in the past, including in connection with the 2020 merger between Menlo (VYNE’s predecessor company) and Foamix and in VYNE’s private placement transaction in November 2023. VYNE may also experience ownership changes in the future as a result of the subsequent shifts in its stock ownership, some of which may be outside of VYNE’s control. Consequently, even if the combined company achieves profitability, it may not be able to utilize a material portion of VYNE’s, Yarrow’s, or the combined company’s NOL carryforwards and other tax attributes, which could have an adverse effect on cash flow and results of operations. For more information on limitations on NOL carryforwards and certain other tax attributes, see “Risk Factors — Risks related to the Combined Company — The Combined Company’s ability to use NOL carryforwards and other tax attributes may be limited, including as a result of the Merger.”

The Israeli Tax Authority may disagree with VYNE’s conclusions regarding certain tax positions, resulting in unanticipated costs, taxes or non-realization of expected benefits.

In December 2020, VYNE initiated a voluntary liquidation of its Israeli subsidiary in order to consolidate the ownership of VYNE’s intellectual property. In connection with the liquidation, the intellectual property and other assets owned by VYNE’s Israeli subsidiary were assigned to VYNE. Based on VYNE’s analysis, it notified the Israeli Tax Authority that the gains realized by VYNE’s Israeli subsidiary from the transfer of its assets to VYNE were offset by NOLs and that the liquidation did not result in tax in Israel under Israeli tax law. In September 2025, the Company closed its tax file with the ITA however, the ITA has until December 31, 2026 to assess the returns. In the event that the Israeli Tax Authority does not agree with VYNE’s analysis, it may be subject to a material tax liability. In addition, VYNE may incur additional costs associated with defending its position. Any such outcome may have a material adverse effect on VYNE’s financial results.

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If VYNE fails to attract and keep senior management and key scientific personnel, it may be unable to successfully execute its strategy.

VYNE’s success depends in part on its continued ability to attract, retain and motivate highly qualified management and clinical and scientific personnel. VYNE believes that its future success is highly dependent upon the contributions of its senior management. The loss of services of any of these individuals could delay or prevent the successful completion of the Merger or, if the Merger is not consummated, preclinical and clinical development of VYNE’s product pipeline.

Competition for qualified personnel in the pharmaceutical field is intense due to the limited number of individuals who possess the skills and experience required by VYNE’s industry. VYNE may need to hire additional personnel as it expand its clinical development activities. VYNE may not be able to attract and retain quality personnel on acceptable terms, or at all. In addition, to the extent VYNE hires personnel from competitors, it may be subject to allegations that they have been improperly solicited or that they have divulged proprietary or other confidential information, or that their former employers own their research output.

In connection with the Merger, VYNE may experience increased employee attrition, challenges to recruiting, and distraction during integration planning and following Closing, which could adversely affect execution of VYNE’s operating plans. Potential adverse reactions among employees and prospective hires arising from the announcement and completion of the Merger, as well as uncertainty regarding roles and organizational structure, could impair retention and hiring.

VYNE may become subject to lawsuits or investigations that could have a material adverse impact on its business, results of operations and financial condition.

From time to time and in the ordinary course of its business, VYNE may become involved in various lawsuits, in addition to product liability lawsuits and lawsuits to protect and enforce VYNE’s intellectual property. These lawsuits may include claims initiated by VYNE’s third-party collaborators, suppliers, manufacturers, former employees, contractors or vendors and claims related to the sale of securities and related disclosure. In addition, VYNE may become involved in an investigation concerning, or indirectly related to, its business activities, including its previous commercial activities. All such lawsuits and investigations are inherently unpredictable and, regardless of the merits of the claims, litigation may be expensive, time-consuming and disruptive to VYNE’s operations and distracting to management. If resolved against VYNE, such lawsuits could result in excessive verdicts, injunctive relief or other equitable relief that may affect how VYNE operates its business. Similarly, if VYNE settles such lawsuits, it may affect how it operates its business. Future court decisions, alternative dispute resolution awards, business expansion or legislative activity may increase VYNE’s exposure to litigation and regulatory investigations. In some cases, substantial non-economic remedies or punitive damages may be sought. Although VYNE maintains liability insurance coverage, including director and officer insurance with liability coverage limits, such coverage may not cover any particular verdict, judgment or settlement that may be entered against VYNE or its officers and directors, and such coverage may not prove to be adequate or such coverage may not continue to remain available on acceptable terms or at all. If VYNE incurs liability that exceeds its insurance coverage or that is not within the scope of the coverage in lawsuits brought against it, it could have a material adverse effect on VYNE’s business, results of operations and financial condition.

If VYNE’s information technology systems or those of third parties upon which VYNE relies or VYNE’s data are, or were, compromised, it could experience adverse consequences resulting from such compromise, including but not limited to regulatory investigations or actions, litigation, fines and penalties, disruptions of VYNE’s business operations, reputational harm, loss of revenue or profits and other adverse consequence.

In the ordinary course of VYNE’s business, it and the third parties upon which it relies process proprietary, confidential, and sensitive data, including personal data (such as health-related data), intellectual property, and trade secrets (collectively, sensitive information) face a variety of evolving threats, including but not limited to cyber extortion, which could cause security incidents. VYNE’s information technology systems and infrastructure, and those of VYNE’s current and any future partners, contractors and consultants, are vulnerable to damage from computer viruses, unauthorized access, natural disasters, terrorism, war and telecommunication and electrical failures. The ever-increasing use and evolution of technology, including cloud-based computing and proliferation of artificial intelligence, creates opportunities for the unintentional dissemination or intentional destruction of confidential information stored in VYNE’s systems or in non-encrypted portable media or storage devices.

Cyber-attacks, malicious internet-based activity, online and offline fraud, and other similar activities threaten the confidentiality, integrity, and availability of VYNE’s sensitive information and information technology systems, and those of the third parties upon which it relies. Such threats are prevalent and continue to rise, are increasingly difficult to detect, and come from a variety of sources,

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including traditional computer “hackers,” threat actors, “hacktivists,” organized criminal threat actors, personnel (such as through theft or misuse), sophisticated nation states, and nation-state-supported actors. Some actors now engage and are expected to continue to engage in cyber-attacks, including without limitation nation-state actors for geopolitical reasons and in conjunction with military conflicts and defense activities. During times of war and other major conflicts, VYNE, and the third parties upon which it relies, may be vulnerable to a heightened risk of these attacks, including retaliatory cyber-attacks, that could materially disrupt VYNE’s systems and operations, supply chain, and ability to produce, sell and distribute its goods and services.

VYNE and the third parties upon which it relies may be subject to a variety of evolving threats, including but not limited to social-engineering attacks (including through phishing attacks), malicious code (such as viruses and worms), malware (including as a result of advanced persistent threat intrusions), denial-of- service attacks (such as credential stuffing), credential harvesting, personnel misconduct or error, ransomware attacks, supply-chain attacks, software bugs, server malfunctions, software or hardware failures, loss of data or other information technology assets, adware, telecommunications failures, attacks enhanced or facilitated by artificial intelligence, and other similar threats. In particular, severe ransomware attacks are becoming increasingly prevalent and can lead to significant interruptions in VYNE’s operations, loss of sensitive data and income, reputational harm, and diversion of funds. Extortion payments may alleviate the negative impact of a ransomware attack, but VYNE may be unwilling or unable to make such payments due to, for example, applicable laws or regulations prohibiting such payments.

VYNE is increasingly dependent upon information technology systems, infrastructure and data to operate its business. Remote work has increased risks to VYNE’s information technology systems and data, as more of VYNE’s employees utilize network connections, computers and devices outside VYNE’s premises or network, including working at home, while in transit and in public locations. Future or past business transactions (such as acquisitions or integrations) could expose VYNE to additional cybersecurity risks and vulnerabilities, as its systems could be negatively affected by vulnerabilities present in acquired or integrated entities’ systems and technologies. Furthermore, VYNE may discover security issues that were not found during due diligence of such acquired or integrated entities, and it may be difficult to integrate companies into VYNE’s information technology environment and security program.

While VYNE has not experienced any such material system failure, accident or security breach to date, if such an event were to occur and cause interruptions in VYNE’s operations, it could cause damage or destroy assets, compromise business systems, result in proprietary information, trade secrets and other sensitive information being altered, lost, stolen, or published and may result in loss of intellectual property and in employee or third-party information being compromised, or otherwise disrupt business operations. For example, the loss of manufacturing records or clinical trial data from completed, ongoing or future clinical trials could result in delays in VYNE’s regulatory approval efforts and significantly increase VYNE’s costs to recover or reproduce the data. To the extent that any disruption or security breach were to result in a loss of, or damage to, VYNE’s data or applications, or inappropriate disclosure of confidential or proprietary information, VYNE could incur liability and the further development of VYNE’s current and any future product candidates could be delayed.

VYNE may expend significant resources or modify business activities to try to protect its information technology systems, infrastructure, and data, without assurances that any security measure or modified practice will be effective as implemented. In the event of a security incident, VYNE may expend additional significant resources in analyzing and responding to each such security incident and related threats or losses. In the event of any such disruption, security breach, or similar incident, VYNE cannot be sure that its insurance coverage will be adequate or sufficient to protect it from or to mitigate liabilities arising out of VYNE’s privacy and security practices, that such coverage will continue to be available on commercially reasonable terms or at all, or that such coverage will pay future claims. Additionally, VYNE’s contracts may contain limitations on liability such that there can be no assurance that the third parties on which VYNE relies would be contractually obligated to indemnify or reimburse it for liabilities, damages, claims, and losses arising from security incidents experienced by, or otherwise attributable in whole or part to, such third parties or the third parties on which they rely.

VYNE’s employees, independent contractors, principal investigators, consultants, vendors, CROs and any partners with which VYNE may collaborate may engage in misconduct or other improper activities, including noncompliance with regulatory standards and requirements, which could have an adverse effect on VYNE’s business.

VYNE is exposed to the risk that VYNE’s employees, independent contractors, principal investigators, consultants, vendors, CROs, distributors, prescribers, pharmacies and any partners with which it may collaborate may engage in fraudulent or other illegal activity. This includes historical misconduct VYNE may inherit in connection with the integration of Yarrow employees and independent contractors into a joint workforce. Misconduct by these persons could include intentional, reckless or negligent conduct or unauthorized activity that violates: laws or regulations, including those laws requiring the reporting of true, complete and accurate

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information to the FDA or foreign regulatory authorities; manufacturing standards; federal, state and foreign healthcare fraud and abuse laws and data privacy; or laws that require the true, complete and accurate reporting of financial information or data. In particular, sales, marketing and other business arrangements in the healthcare industry are subject to extensive laws intended to prevent fraud, kickbacks, self-dealing and other abusive practices. These laws may restrict or prohibit a wide range of business activities, including research, manufacturing, distribution, pricing, discounting, marketing and promotion, sales commissions, customer incentive programs and other business arrangements. Activities subject to these laws also involve the improper use of information obtained in the course of clinical trials, or illegal misappropriation of drug product, which could result in regulatory sanctions or other actions or lawsuits stemming from a failure to be in compliance with such laws or regulations, and serious harm to VYNE’s reputation. In addition, federal procurement laws impose substantial penalties for misconduct in connection with government contracts and require certain contractors to maintain a code of business ethics and conduct. If any such actions are instituted against VYNE, and it are not successful in defending itself or asserting its rights, those actions could have a significant impact on VYNE’s business, including the imposition of civil, criminal and administrative penalties, damages, monetary fines, possible exclusion from participation in Medicare, Medicaid and other federal healthcare programs, contractual damages, reputational harm, diminished profits and future earnings, and curtailment of VYNE’s operations, any of which could adversely affect VYNE’s ability to operate VYNE’s business and VYNE’s operating results.

Unfavorable global economic conditions could adversely affect VYNE’s business, financial condition or results of operations.

A severe or prolonged economic downturn could result in a variety of risks to VYNE’s business, including VYNE’s ability to raise additional capital when needed on acceptable terms, if at all. A weak or declining economy could also strain VYNE’s suppliers, possibly resulting in supply disruption and ultimately delaying VYNE’s development activities. For example, inflation rates, particularly in the United States and United Kingdom, have increased recently to levels not seen in years, and increased inflation may result in increases in VYNE’s operating costs (including VYNE’s labor costs), reduced liquidity and limits on VYNE’s ability to access credit or otherwise raise capital. In addition, the Federal Reserve has raised, and may again raise, interest rates in response to concerns about inflation, which coupled with reduced government spending and volatility in financial markets may have the effect of further increasing economic uncertainty and heightening these risks. Additionally, global commerce has experienced periods of volatility and interruption following the invasion of Ukraine by Russia in February 2022 and the escalation of conflict in the Middle East in October 2023. In early 2025, the U.S. government also began imposing tariffs on certain foreign products, including products from China, which may lead to retaliatory tariff policies from other nations and result in increased costs of conducting VYNE’s business. Any of the foregoing could harm VYNE’s business and VYNE cannot anticipate all of the ways in which the current economic climate and geopolitical and financial market conditions could adversely impact VYNE’s business.

Risks Related to Government Regulation

VYNE is subject to various U.S. federal, state, local and foreign health care fraud and abuse laws, including anti-kickback, self-referral, false claims and fraud laws, health information privacy and security, and transparency laws, and any violations by VYNE of such laws could result in substantial penalties or other consequences including criminal sanctions, civil penalties, contractual damages, reputational harm, and diminished profits and future earnings. Additionally, any challenge to or investigation into VYNE’s practices under these laws could cause adverse publicity and be costly to respond to, and thus could harm VYNE’s business.

There are numerous U.S. federal, state, local and foreign health care fraud and abuse laws pertaining to VYNE’s business, including anti-kickback, false claims and physician transparency laws. VYNE’s business practices and relationships with providers, patients and third-party payors are subject to scrutiny under these laws. These laws may impact, among other things, VYNE’s potential sales, marketing, patient assistance and education programs. VYNE may also be subject to patient information privacy and security regulation by both the federal government, states and foreign jurisdictions in which VYNE conduct its business. The healthcare laws and regulations that may affect VYNE’s ability to operate include:

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These and similar laws may be subject to amendment or reinterpretation, and implementing regulations may be revised or reinterpreted, in ways that may significantly affect VYNE’s business. State and federal authorities have aggressively targeted pharmaceutical companies for alleged violations of these fraud and abuse laws based on improper research or consulting contracts with doctors, certain marketing arrangements that rely on volume-based pricing, off-label marketing schemes, and other improper promotional practices.

Efforts to ensure that VYNE’s business arrangements with third parties will comply with applicable healthcare laws and regulations will involve substantial costs. It is possible that governmental authorities will conclude that VYNE’s business practices do not comply with current or future statutes, regulations or case law involving applicable fraud and abuse or other healthcare laws and regulations. If VYNE’s operations are found to be in violation of any of the health regulatory laws described above or any other laws or regulations that apply to VYNE, it may be subject to significant penalties, including criminal, civil and administrative penalties, damages, fines, disgorgement, individual imprisonment, exclusion from participation in government healthcare programs, debarment from contracting with the U.S. government, injunctions and private qui tam actions brought by individual whistleblowers in the name of the government. Companies targeted in such actions have, among other consequences, paid substantial fines in the hundreds of millions of dollars or more, have been forced to implement extensive corrective action plans, and have often become subject to consent decrees or corporate integrity agreements that severely restrict the manner in which they conduct their business, including the requirement of additional reporting and oversight obligations. Due to the breadth of these laws, the narrowness of statutory exceptions and regulatory safe harbors available, and the range of interpretations to which they are subject, it is possible that some of VYNE’s current or future practices might be challenged under one or more of these laws. Responding to investigations, enforcement actions and litigation can be time-and resource consuming and can divert management’s attention from the business. Any such investigation, action, litigation or settlement could increase VYNE’s costs or otherwise have an adverse effect on VYNE’s business and reputation. Even an unsuccessful challenge or investigation into VYNE’s practices could cause adverse publicity and be costly to respond to. In addition, the approval and commercialization of any of VYNE’s product candidates outside the U.S. will also likely subject it to non-U.S. equivalents of the healthcare laws mentioned above, among other non-U.S. laws.

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VYNE and third parties with whom it works are subject to stringent and evolving U.S. and foreign laws, regulations, and rules, contractual obligations, industry standards, policies and other obligations related to data privacy and security. VYNE’s actual or perceived failure to comply with such obligations could lead to regulatory investigations or actions; litigation (including class claims) and mass arbitration demands; fines and penalties; disruptions of VYNE’s business operations; reputational harm; loss of revenue or profits; and other adverse business consequences.

In the ordinary course of business, VYNE collects, receives, stores, processes, generates, uses, transfers, discloses, makes accessible, protects, secures, disposes of, transmits, and shares (collectively, processes) personal data and other sensitive information, including proprietary and confidential business data, trade secrets, intellectual property, data VYNE collects about trial participants in connection with clinical trials, sensitive third-party data, business plans, transactions, and financial information. The data processing activities related to VYNE’s work subject it and the third parties with whom it works to numerous data privacy and security obligations, such as various laws, regulations, guidance, industry standards, external and internal privacy and security policies, contractual requirements, and other obligations relating to data privacy and security.

In the United States, federal, state, and local governments have enacted numerous data privacy and security laws, including data breach notification laws, personal data privacy laws, consumer protection laws (e.g., Section 5 of the Federal Trade Commission Act), and other similar laws.

Numerous U.S. states have enacted comprehensive privacy laws that impose certain obligations on covered businesses, including providing specific disclosures in privacy notices and affording residents with certain rights concerning their personal data. As applicable, such rights may include the right to access, correct, or delete certain personal data, and to opt-out of certain data processing activities, such as targeted advertising, profiling, and automated decision-making. The exercise of these rights may impact VYNE’s business and ability to provide VYNE’s products and services.

Certain states also impose stricter requirements for processing certain personal data, including sensitive information, such as conducting data privacy impact assessments. These state laws allow for statutory fines for noncompliance. For example, the California Consumer Privacy Act of 2018, as amended by the California Privacy Rights Act of 2020 (“CPRA”), (collectively, “CCPA”) applies to personal data of consumers, business representatives, and employees who are California residents, and requires businesses to provide specific disclosures in privacy notices and honor requests of such individuals to exercise certain privacy rights. The CCPA provides for fines of up to $7,500 per intentional violation and allows private litigants affected by certain data breaches to recover significant statutory damages. Although the CCPA exempts some data processed in the context of clinical trials, the CCPA increases compliance costs and potential liability with respect to other personal data VYNE maintains about California residents. Similar laws are being considered in several other states, as well as at the federal and local levels, and VYNE expects more states to pass similar laws in the future. While these states, like the CCPA, also exempt some data processed in the context of clinical trials, these developments further complicate compliance efforts and increase legal risk and compliance costs for VYNE and the third parties upon whom it relies.

Outside the United States, an increasing number of laws, regulations, and industry standards govern data privacy and security. For example, the European Union’s General Data Protection Regulation (“EU GDPR”), the United Kingdom’s GDPR (“UK GDPR”), Brazil’s General Data Protection Law, and China’s Personal Information Protection Law (“PIPL”) impose strict requirements for processing personal data. For example, under the GDPR, companies may face temporary or definitive bans on data processing and other corrective actions; fines of up to 20 million Euros under the EU GDPR, 17.5 million pounds sterling under the UK GDPR or, in each case, 4% of annual global revenue, whichever is greater; or private litigation related to processing of personal data brought by classes of data subjects or consumer protection organizations authorized at law to represent their interests.

In the ordinary course of business, VYNE may transfer personal data from Europe and other jurisdictions to the United States or other countries. Europe and other jurisdictions have enacted laws requiring data to be localized or limiting the transfer of personal data to other countries. In particular, the European Economic Area (“EEA”) and the United Kingdom (“UK”) have significantly restricted the transfer of personal data to the United States and other countries whose privacy laws it generally believes are inadequate. Other jurisdictions may adopt or have already adopted similarly stringent data localization and cross-border data transfer laws.

Although there are currently various mechanisms that may be used to transfer personal data from the EEA and UK to the United States in compliance with law, such as the EEA standard contractual clauses, the UK’s International Data Transfer Agreement / Addendum, and the EU-U.S. Data Privacy Framework and the UK extension thereto (which allows for transfers to relevant U.S.-based organizations who self-certify compliance and participate in the Framework), these mechanisms are subject to legal challenges, and there is no assurance that VYNE can satisfy or rely on these measures to lawfully transfer personal data to the United States.

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If there is no lawful manner for VYNE to transfer personal data internationally (such as from the EEA, the UK or other jurisdictions to the United States or from the United States to China or other countries of concern), or if the requirements for a legally-compliant transfer are too onerous, VYNE could face significant adverse consequences, including the interruption or degradation of VYNE’s operations, the need to relocate part of or all of VYNE’s business or data processing activities to other jurisdictions (such as Europe or Asia) at significant expense, increased exposure to regulatory actions, substantial fines and penalties, the inability to transfer data and work with partners, vendors and other third parties, and injunctions against VYNE’s processing or transferring of personal data necessary to operate VYNE’s business. Additionally, companies that transfer personal data internationally, including out of the EEA and UK to other jurisdictions, particularly to the United States, are subject to increased scrutiny from regulators, individual litigants, customers and partners, and activist groups.

Obligations related to data privacy and security (and consumers’ data privacy expectations) are quickly changing, becoming increasingly stringent, and creating uncertainty. Additionally, these obligations may be subject to differing applications and interpretations, which may be inconsistent or conflict among jurisdictions. Preparing for and complying with these obligations requires VYNE to devote significant resources, which may necessitate changes to its services, information technologies, systems, and practices and to those of any third parties that process personal data on VYNE’s behalf. VYNE may at times fail (or be perceived to have failed) in its efforts to comply with its data privacy and security obligations. Moreover, despite VYNE’s efforts, its personnel or third parties with whom it works may fail to comply with such obligations, which could negatively impact VYNE’s business operations.

If VYNE or the third parties with whom it works fail, or are perceived to have failed, to address or comply with applicable data privacy and security obligations, VYNE could face significant consequences, including but not limited to: government enforcement actions (e.g., investigations, fines, penalties, audits, inspections, and similar); litigation (including class-action claims) and mass arbitration demands; additional reporting requirements and/or oversight; bans or restrictions on processing personal data; or orders to destroy or not use personal data. Any of these events could have a material adverse effect on VYNE’s reputation, business, or financial condition, including but not limited to: loss of customers; inability to process personal data or to operate in certain jurisdictions; limited ability to develop or commercialize VYNE’s products; expenditure of time and resources to defend any claim or inquiry; adverse publicity; or substantial changes to VYNE’s business model or operations.

When VYNE’s employees and personnel use generative artificial intelligence, agentic artificial intelligence, automated decision-making tools, or other artificial intelligence (collectively, “AI”) technologies to perform their work, VYNE may be subject to various laws and regulations, such as those governing the specific application of AI technologies, the disclosure and use of personal data in generative AI technologies, or an individual’s interactions with AI technologies. Governments have passed and are likely to pass additional laws regulating AI technologies. Additionally, VYNE’s use of AI technology could result in additional compliance costs, regulatory investigations and actions, and lawsuits. VYNE’s use of AI technology also inherently results in increased risk to VYNE’s information technology systems, infrastructure, and data. If VYNE is unable to use AI technologies, or if significant restrictions or limitations apply to VYNE’s intended use of AI technologies, it could make VYNE’s business less efficient and result in competitive disadvantages. Obligations relating to the use of AI technologies are quickly changing, becoming increasingly stringent, and creating uncertainty. Similarly, the known and foreseeable risks arising from the use of AI technologies are quickly changing, becoming increasingly severe or difficult to mitigate, and creating uncertainty.

Healthcare reforms by governmental authorities and related reductions in pharmaceutical pricing, reimbursement and coverage by third party payors may adversely affect VYNE’s business.

VYNE expects the healthcare industry to face increased limitations on reimbursement, rebates and other payments as a result of healthcare reform, which could adversely affect third party coverage of any future products and how much or under what circumstances healthcare providers will prescribe or administer VYNE’s products, if approved.

In both the United States and other countries, sales of VYNE’s products, if approved, will depend in part upon the coverage and adequate reimbursement from third party payors, which include governmental authorities, managed care organizations and other private health insurers. Third party payors include government health administrative authorities, managed care providers, private health insurers and other organizations. The process for determining whether a payor will provide coverage for a drug product may be separate from the process for setting the price or reimbursement rate that the payor will pay for the drug product. Third party payors may limit coverage to specific drug products on an approved list, or formulary, which might not include all of the FDA-approved drug products for a particular indication. Third party payors are increasingly challenging the price and examining the cost effectiveness of medical products and services. A payor may not consider a product to be medically necessary or cost-effective. Moreover, a payor’s decision to provide coverage for a drug product does not imply that an adequate reimbursement rate will be approved, or that other

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payors will similarly provide similar coverage for the product. Adequate third-party reimbursement may not be available to enable VYNE to maintain price levels sufficient to realize an appropriate return on its investment in product development.

Increasing expenditures for healthcare have been the subject of considerable public attention in the United States. Both private and government entities are seeking ways to reduce or contain healthcare costs. Numerous proposals that would effect changes in the U.S. healthcare system have been introduced or proposed in Congress and in some state legislatures, including reducing reimbursement for prescription products and reducing the levels at which consumers and healthcare providers are reimbursed for purchases of pharmaceutical products.

Cost reduction initiatives and changes in coverage implemented through legislation or regulation could decrease utilization of and reimbursement for any approved products, which in turn would affect the price VYNE can receive for those products. Any reduction in reimbursement that results from federal legislation or regulation may also result in a similar reduction in payments from private payors, as private payors often follow Medicare coverage policy and payment limitations in setting their own reimbursement rates.

Significant developments that may adversely affect pricing in the United States include the enactment of federal healthcare reform laws and regulations. Changes in the healthcare system enacted as part of healthcare reform in the United States, as well as the increased purchasing power of entities that negotiate on behalf of Medicare, Medicaid, and private sector beneficiaries, may result in increased pricing pressure by influencing, for instance, the reimbursement policies of third party payors. While healthcare reform legislation, such as the ACA, may have increased the number of patients who are expected to have insurance coverage for VYNE’s product candidates, provisions such as the assessment of a branded pharmaceutical manufacturer fee and an increase in the amount of rebates that manufacturers pay for coverage of their drugs by Medicaid programs may have an adverse effect on VYNE. It is uncertain how current and future reforms in these areas will influence the future of VYNE’s business operations and financial condition.

Since its enactment, there have been judicial, Congressional and political challenges and amendments to certain aspects of the ACA. For example, on August 16, 2022, the Inflation Reduction Act of 2022 (“IRA”) was signed into law, which among other things, extends enhanced subsidies for individuals purchasing health insurance coverage in ACA marketplaces through plan year 2025. The IRA also eliminates the “donut hole” under the Medicare Part D program beginning in 2025 by significantly lowering the beneficiary maximum out-of-pocket cost and creating a new manufacturer discount program. Additionally, on July 4, 2025, the One Big Beautiful Bill Act (the “OBBBA”) was signed into law, which is expected to reduce Medicaid spending and enrollment by implementing work requirements for some beneficiaries, capping state-directed payments, reducing federal funding, and limiting provider taxes used to fund the program. The OBBBA also narrowed access to ACA marketplace exchange enrollment and declined to extend the ACA enhanced advanced premium tax credits that expired at the end of 2025, which, among other provisions in the law, are anticipated to reduce the number of Americans with health insurance. Congress is considering proposed legislation intended to further reduce healthcare costs with alternatives to replace the expired ACA subsidies. It is possible that the ACA will be subject to judicial or Congressional challenges in the future. It is unclear how any such challenges, if any, and additional reform measures of the second Trump administration will impact the ACA.

Although VYNE cannot predict the full effect on its business of the enactment of additional legislation pursuant to healthcare and other legislative reform, VYNE believes that legislation or regulations that would reduce reimbursement for, or restrict coverage of, any future products could adversely affect how much or under what circumstances healthcare providers will prescribe or administer any products VYNE markets in the future. This could materially and adversely affect VYNE’s business by reducing VYNE’s ability to generate revenues, raise capital, obtain additional licensees, and market VYNE’s products, if approved. In addition, VYNE believes the increasing emphasis on managed care in the United States has and will continue to put pressure on the price and usage of pharmaceutical products, which may adversely impact product sales.

Recently there has been heightened governmental scrutiny over the manner in which manufacturers set prices for their marketed products, which has resulted in several U.S. Congressional inquiries and proposed federal legislation designed to, among other things, bring more transparency to product pricing, reduce the cost of certain products under Medicare, review the relationship between pricing and manufacturer patient programs, and reform government program reimbursement methodologies. For example, the IRA, among other things (i) directed the U.S. Department of Health and Human Services (“HHS”) to negotiate the price of certain high-expenditure, single-source drugs that have been on the market for at least 7 years covered under Medicare (the “Medicare Drug Price Negotiation Program”), and (ii) imposed rebates under Medicare Part B and Medicare Part D to penalize price increases that outpace inflation. Each year up to twenty (20) products will be selected by HHS for the Medicare Drug Price Negotiation Program. Products subject to the Medicare Drug Price Negotiation Program are expected to experience a significant reduction in reimbursement from the Medicare program on a per unit basis. Further, on December 7, 2023, an initiative to control the price of prescription drugs through the use of march-in rights under the Bayh-Dole Act was announced. On December 8, 2023, the National Institute of Standards and

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Technology published for comment a Draft Interagency Guidance Framework for Considering the Exercise of March-In Rights which for the first time includes the price of a product as one factor an agency can use when deciding to exercise march-in rights. While march-in rights have not previously been exercised, it is uncertain if that will continue under the new framework. At the state level, individual states in the United States are also increasingly passing legislation and implementing regulations designed to control product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures.

It is likely that additional state and federal healthcare reform measures will be adopted in the future, particularly in light of the recent U.S. Presidential and Congressional elections, any of which could limit the amounts that federal and state governments will pay for healthcare products and services, which could result in reduced demand for a pharmaceutical manufacturer’s products or additional pricing pressure.

Legislative or regulatory healthcare reforms in the United States may make it more difficult and costly for VYNE to obtain regulatory clearance or approval of its product candidates and to produce, market, and distribute its products after clearance or approval is obtained.

From time to time, legislation is drafted and introduced in Congress that could significantly change the statutory provisions governing the regulatory clearance or approval, manufacture, and marketing of regulated products or the reimbursement thereof. In addition, FDA regulations and guidance are often revised or reinterpreted by the FDA in ways that may significantly affect VYNE’s business. Any new regulations or revisions or reinterpretations of existing regulations may impose additional costs or lengthen review times of any of VYNE’s product candidates.

The current administration is pursuing policies to reduce regulations and expenditures across government including at HHS, the FDA, CMS and related agencies. These actions, presently directed by executive orders or memoranda from the Office of Management and Budget, may propose policy changes that create additional uncertainty for VYNE’s business. For example, the current administration has announced agreements with several pharmaceutical companies that require the drug manufacturers to offer, through a direct to consumer platform, U.S. patients and Medicaid programs prescription drug Most- Favored Nation pricing equal to or lower than those paid in other developed nations, with additional mandates for direct-to-patient discounts and repatriation of foreign revenues. Other recent actions, for example, include (1) directives to reduce agency workforce and cut programs; (2) directing HHS and other agencies to lower prescription drug costs through a variety of initiatives, including by improving upon the Medicare Drug Price Negotiation Program and establishing Most-Favored-Nation pricing for pharmaceutical products; (3) imposing tariffs on imported pharmaceutical products; and (4) as part of the Make America Healthy Again (“MAHA”) Commission’s recent Strategy Report, working across government agencies to increase enforcement on direct-to-consumer pharmaceutical advertising. Additionally, the current administration recently called on Congress to enact “The Great Healthcare Plan,” to codify and expand Most-Favored Nation pricing, lower government subsidies to private insurance companies, increase healthcare price transparency, expand pharmaceutical drugs available for over-the-counter purchase, and enact restrictions on pharmacy benefit manager (PBM) payment methodologies, among other things. These actions and policies may significantly reduce U.S. drug prices, potentially impacting manufacturers’ global pricing strategies and profitability, while increasing their operational costs and compliance risks. In June 2024, the U.S. Supreme Court’s Loper Bright decision greatly reduced judicial deference to regulatory agencies, which could increase successful legal challenges to federal regulations affecting VYNE’s operations. VYNE cannot determine what effect changes in regulations, statutes, legal interpretation or policies, when and if promulgated, enacted or adopted may have on VYNE’s business in the future. Such changes could, inter alia, require:

Each of these would likely entail substantial time and cost and could adversely affect VYNE’s business and VYNE’s financial results. VYNE cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative or judicial action in the United States or any other jurisdiction. If VYNE or any third parties it may engage are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if VYNE or such third parties are not able to maintain regulatory compliance, VYNE’s product candidates may lose any regulatory approval that may have been obtained and VYNE may not achieve or sustain profitability.

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VYNE and any of the contract manufacturers on which it relies, or may rely in the future, are subject to significant regulation with respect to manufacturing of VYNE’s product candidates. The manufacturing facilities on which VYNE relies, or may rely in the future, may not continue to meet regulatory requirements and have limited capacity.

VYNE and any contract manufacturers for its product candidates are subject to extensive regulation. Some components of a finished drug product used in late-stage clinical studies must be manufactured in accordance with current good manufacturing practices (“cGMP”). These regulations govern manufacturing processes and procedures (including record keeping) and the implementation and operation of quality systems to control and assure the quality of investigational products and products approved for sale. Poor control of production processes can lead to the introduction of adventitious agents or other contaminants, or to inadvertent changes in the properties or stability of VYNE’s product and product candidates that may not be detectable in final product testing. VYNE or its contract manufacturers must supply all necessary documentation in support of regulatory applications on a timely basis and where required, must adhere to the FDA’s or other regulator’s good laboratory practices and cGMP regulations enforced by the FDA or other regulator through facilities inspection programs. VYNE’s facilities and quality systems and the facilities and quality systems of some or all of VYNE’s third-party contractors must pass a pre-approval inspection for compliance with the applicable regulations as a condition of marketing approval of VYNE’s product and potential products. In addition, the regulatory authorities may, at any time, audit or inspect a manufacturing facility involved with the preparation of VYNE’s product candidates or the associated quality systems for compliance with the regulations applicable to the activities being conducted. If these facilities do not pass a pre-approval plant inspection, FDA or other marketing approval of the products may not be granted.

The regulatory authorities also may, at any time following approval of a product for sale, audit the manufacturing facilities of VYNE’s third-party contractors. If any such inspection or audit identifies a failure to comply with applicable regulations or if a violation of VYNE’s product specifications or applicable regulations occurs independent of such an inspection or audit, VYNE or the relevant regulatory authority may require remedial measures that may be costly and/or time-consuming for VYNE or a third party to implement and that may include the temporary or permanent suspension of a clinical trial or commercial sales or the temporary or permanent closure of a facility. Any such remedial measures imposed upon VYNE or third parties with whom it contracts could materially harm VYNE’s business.

If VYNE or any of its third-party manufacturers fail to maintain regulatory compliance, the FDA or other regulators can impose regulatory sanctions including, among other things, refusal to approve a pending application for a product, or revocation of a pre-existing approval. As a result, VYNE’s business, financial condition and results of operations may be materially harmed.

Additionally, if supply from one approved manufacturer is interrupted, there could be a significant disruption in supply. The number of manufacturers with the necessary manufacturing capabilities is limited. Switching manufacturers may involve substantial costs and is likely to result in a delay in VYNE’s desired clinical timelines.

These factors could cause the delay of clinical studies, regulatory submissions, or required approvals of any future products, and cause VYNE to incur higher costs. Furthermore, if VYNE’s suppliers fail to meet contractual requirements and VYNE is unable to secure, validate and obtain approval of one or more replacement suppliers capable of production at a substantially equivalent cost, VYNE’s clinical studies may be delayed or VYNE could lose potential revenues.

Changes in funding for the FDA and other government agencies could hinder their ability to hire and retain key leadership and other personnel, prevent new products and services from being developed or commercialized in a timely manner or otherwise prevent those agencies from performing normal functions on which the operation of VYNE’s business may rely, which could negatively impact VYNE’s business.

The ability of the FDA to review and approve new products can be affected by a variety of factors, including government budget and funding levels, ability to hire and retain key personnel and accept payment of user fees, and statutory, regulatory, and policy changes. Average review times at the agency have fluctuated in recent years as a result. In addition, government funding other government agencies on which VYNE’s operations may rely, including those that fund research and development activities is subject to the political process, which is inherently fluid and unpredictable.

Disruptions at the FDA and other agencies may also slow the time necessary for new drugs to be reviewed and/or approved by necessary government agencies, which would adversely affect VYNE’s business. For example, over the last several years, including in October 2025, the U.S. government has shut down several times and certain regulatory agencies, such as the FDA, have had to furlough critical government employees and stop critical activities. If a prolonged government shutdown occurs, it could significantly impact the ability of the FDA to timely review and process VYNE’s regulatory submissions, and such delays could have a material

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adverse effect on VYNE’s business. Further, future government shutdowns could impact VYNE’s ability to access the public markets and obtain necessary capital in order to properly capitalize and continue VYNE’s operations. In addition, the current administration has implemented substantial reductions in force at various government agencies including the FDA, and has implemented layoffs at the FDA, which could significantly reduce the FDA’s capacity to perform its functions in a manner consistent with its past practices and could delay reviews and negatively impact VYNE’s business.

VYNE is subject to various U.S. and foreign anti-bribery and anti-corruption laws, and any violations by it of such laws could result in substantial penalties.

The U.S. Foreign Corrupt Practices Act (“FCPA”), and similar worldwide anti-bribery and anti- corruption laws, generally prohibit U.S. individuals, companies, and their intermediaries from directly or indirectly offering, making or authorizing improper payments or the provision of anything of value to government officials for the purpose of obtaining or retaining business. The FCPA also obligates companies whose securities are listed in the United States to comply with accounting provisions requiring the company to maintain books and records that accurately and fairly reflect all transactions of the corporation, including international subsidiaries, and to devise and maintain an adequate system of internal accounting controls. VYNE’s internal control policies and procedures may not protect it from reckless or negligent acts committed by its employees, future distributors, licensees or agents. Violations of these laws, or allegations of such violations, could result in fines, penalties or prosecution and have a negative impact on VYNE’s business, results of operations and reputation.

VYNE’s business involves the use of hazardous materials and VYNE and its third party manufacturers and suppliers must comply with environmental laws and regulations, which can be expensive and restrict how VYNE does business.

VYNE’s research and development activities and VYNE’s third party subcontractors’ and suppliers’ activities involve the controlled storage, use and disposal of hazardous materials owned by VYNE, including key components of VYNE’s product candidates, and other hazardous compounds. VYNE and its manufacturers and suppliers are subject to laws and regulations governing the use, manufacture, storage, handling and disposal of these hazardous materials. In some cases, these hazardous materials are stored at VYNE’s and VYNE’s subcontractors’ facilities pending their use and disposal.

Despite VYNE’s efforts, it cannot eliminate the risk of contamination. This could cause an interruption of VYNE’s development efforts and business operations, environmental damage resulting in costly clean-up and liabilities under applicable laws and regulations governing the use, storage, handling and disposal of these materials and specified waste products. Although VYNE believes that the safety procedures utilized by it and its subcontractors and suppliers for handling and disposing of these materials generally comply with the standards prescribed by these laws and regulations, this may not be the case and there may be risk of accidental contamination or injury from these materials. In such an event, VYNE may be held liable for any resulting damages and such liability could exceed VYNE’s resources and state or federal or other applicable authorities may curtail VYNE’s use of certain materials and interrupt VYNE’s business operations.

Furthermore, environmental laws and regulations are complex, change frequently and have tended to become more stringent. VYNE cannot predict the impact of such changes and cannot be certain of its future compliance.

Sanctions and other trade control laws create the potential for significant liabilities, penalties and reputational harm.

VYNE may be subject to national laws as well as international treaties and conventions controlling imports, exports, re-export and diversion of goods, services and technology. These include import and customs laws, export controls, trade embargoes and economic sanctions, denied party watch lists and anti- boycott measures (collectively “Customs and Trade Controls”). Applicable Customs and Trade Controls are administered by the U.S. Treasury’s Office of Foreign Assets Control, the U.S. Commerce Department’s Bureau of Industry and Security, Israel’s Ministry of Finance, and other agencies of other jurisdictions where VYNE does business. Customs and Trade Controls relate to a number of aspects of VYNE’s business, including most notably the sales of API as well as the licensing of intellectual property. Customs and Trade Controls have been the subject of increasing focus and activity by regulatory authorities, both in the United States and elsewhere, in recent years. Compliance with Customs and Trade Controls may create delays in the introduction of VYNE’s products in international markets or, in some cases, prevent the export of VYNE’s products to some countries altogether. Furthermore, Customs and Trade Controls may prohibit the provision of certain products and services to countries, governments, and persons targeted by sanctions. Although VYNE has policies and procedures designed to address compliance with Customs and Trade Controls, actions by VYNE’s employees, by third-party intermediaries or others acting on VYNE’s behalf in violation of relevant laws and regulations may expose VYNE to liability and penalties for violations of Customs

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and Trade Controls and accordingly may have a material adverse effect on VYNE’s reputation and VYNE’s business, financial condition and results of operations.

Risks Related to VYNE’s Intellectual Property

If VYNE’s efforts to obtain, protect or enforce VYNE’s patents and other intellectual property rights related to any of VYNE’s product candidates are not adequate, VYNE may not be able to compete effectively and it otherwise may be harmed.

VYNE’s success depends in part on its ability to obtain and maintain patent protection and other intellectual property rights and to utilize trade secret protection for VYNE’s intellectual property and proprietary technologies, VYNE’s product candidates and their uses, as well as VYNE’s ability to operate without infringing upon the proprietary rights of others. VYNE relies upon a combination of patents, trade secret protection, trademarks, domain names, trade dress, copyright, confidentiality agreements, assignment of invention agreements and other contractual arrangements to protect the intellectual property related to VYNE’s programs. Limitations on the scope of VYNE’s intellectual property rights may limit VYNE’s ability to defend VYNE’s product candidates and to prevent third parties from designing around such rights and competing against VYNE. Other parties may compete with VYNE, for example, by independently developing or obtaining competing compounds and formulations and methods of manufacture that design around VYNE’s various patent claims, or by using formulations from expired patents, but which may contain the same active ingredients, and or by opposing VYNE’s applications or seeking to invalidate VYNE’s patents. In addition, other parties may seek to impede VYNE or limit its ability to operate, and or seek to compete with VYNE, for example, by filing patent applications directed to methods of manufacture of VYNE’s compounds, directed to methods of use of VYNE’s compounds, and or directed to formulations for use with VYNE’s compounds.

The pending patent applications in relation to repibresib gel and VYN202 are primarily licensed in from Tay and are subject to the terms and conditions of the respective licenses. If VYNE were unable to comply with the license terms, VYNE could be at risk of potentially forfeiting the licenses and rights to these pending patent applications, which could revert back to the licensors, and VYNE would then no longer be able to pursue these programs.

VYNE’s ability to file, prosecute and obtain issued patents in the United States and in key foreign jurisdictions and the expiration dates of such patents, if granted, will limit VYNE’s ability to profit from the commercialization of VYNE’s product candidates, if approved, as may challenges to VYNE’s patent applications and claims. Furthermore, any disclosure to or misappropriation by third parties of VYNE’s confidential or proprietary information could enable competitors to quickly duplicate or surpass VYNE’s technological achievements, thus eroding VYNE’s competitive position in VYNE’s market.

In patent litigation in the United States, defendant counterclaims alleging invalidity and/or unenforceability are commonplace. The outcome following legal assertions of invalidity and unenforceability is unpredictable. With respect to validity, for example, there may be an invalidating prior art, of which VYNE and the patent examiner were unaware during prosecution. If a party were to prevail on a legal assertion of invalidity and/or unenforceability against VYNE’s intellectual property related to one or more of VYNE’s product candidates, VYNE would lose at least part, and perhaps all, of the patent protection on such products or product candidates. Such a loss of patent protection would have a material adverse impact on VYNE’s business.

VYNE’s pending patent applications may not issue, or the scope of the claims of patent applications that do issue may be too narrow or inadequate to provide or protect a competitive advantage. Even if these patents do successfully issue, third parties may challenge the validity, enforceability or scope of such granted patents or any other granted patents VYNE owns or licenses, which may result in such patents being narrowed, invalidated, or held unenforceable.

VYNE has in-licensed intellectual property necessary to develop VYNE’s BET inhibitor product candidates, and if VYNE fails to comply with its obligations under any of these arrangements, it could lose such intellectual property rights.

VYNE has in-licensed its BET inhibitor compounds from Tay. VYNE’s arrangements impose various development, royalty and other obligations on it. If VYNE materially breach these obligations or if VYNE’s counterparts fail to adequately perform their respective obligations, these exclusive arrangements could be terminated, which would result in VYNE’s inability to develop, manufacture and sell BET inhibitor products that are covered by such intellectual property.

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Since patent applications in the United States and most other countries are confidential for a period of time after filing, VYNE cannot be certain that it or its licensor were the first to (i) file any patent application related to VYNE’s product candidates or (ii) conceive and invent any of the inventions claimed in VYNE’s patents or patent applications or in VYNE’s licensed in patents or patent applications.

The United States utilizes a “first-to-file” system for deciding which party should be granted a patent when two or more patent applications are filed by different parties claiming the same invention. A third party that files a patent application in the United States Patent and Trademark Office (“USPTO”) under the first-to-file system before VYNE could be awarded a patent covering an invention of VYNE’s even if VYNE had made the invention before it was made by the third party.

Other patent laws limit where a patentee may file a patent infringement suit and provide opportunities for third parties to challenge any issued patent in the USPTO. The USPTO Patent Trial and Appeal Board (“PTAB”) applies the same claim construction standard applied by civil courts under 35 USC §282(b) in IPR, post-grant review, and the transitional program for covered business method patents proceedings. The impact this may have in practice on the use and outcome of USPTO proceedings is uncertain. PTAB proceedings continue to be a developing and uncertain area of practice and law. Because of lower costs and the fact that USPTO statistics indicate that a high rate of challenged claims are being invalidated in these USPTO procedures, they may continue to be a popular and effective means of challenging patents.

Even where patent, trade secret and other intellectual property laws provide protection, costly and time-consuming litigation could be necessary to enforce and determine the scope of VYNE’s proprietary rights, and the outcome of such litigation would be uncertain. Moreover, any actions VYNE may bring to enforce its intellectual property against its competitors could provoke actions or counterclaims against VYNE, and its competitors have intellectual property of their own, some of which include substantial patent portfolios. An unfavorable outcome could have a material adverse effect on VYNE’s business and could result in the challenged patent(s) or one or more of claims being interpreted narrowly or invalidated, or held not to be infringed, or one or more of VYNE’s patent applications may not be granted.

VYNE also relies on trade secret protection and confidentiality agreements to protect its know-how, data and information e.g., prior to filing patent applications and during the period before they are published. VYNE additionally relies on trade secret protection and confidentiality agreements to protect proprietary know-how that it considers may be maintained as a trade secret rather than the subject of a patent application. VYNE further relies on trade secret protection and confidentiality agreements to protect proprietary know- how that may not be patentable, processes for which patents may be difficult to obtain or enforce and other elements of VYNE’s product development processes that involve proprietary know-how, information or technology that is not covered by patents. VYNE additionally relies on trade secret protection and confidentiality agreements to protect proprietary inventions and related know-how before patent applications are filed and published. VYNE also enters into and relies on, where appropriate, common interest agreements to protect privileged confidential information.

In an effort to protect VYNE’s trade secrets and other confidential information, VYNE incorporates confidentiality provisions in all its employees’ agreements and requires its consultants, contractors and licensees to which it discloses such information to execute confidentiality agreements upon the commencement of their relationships with VYNE. These agreements require that confidential information, as defined in the agreement and disclosed to the individual by VYNE during the course of the individual’s relationship with it, be kept confidential and not disclosed to third parties for an agreed term. These agreements, however, may not provide VYNE with adequate protection against accidental or improper use or disclosure of confidential information, and these agreements may be breached. Adequate remedies may not exist in the event of unauthorized use or disclosure of VYNE’s confidential information. A breach of confidentiality could significantly affect VYNE’s competitive position and VYNE could lose its trade secrets, or they could become otherwise known, or be independently discovered by VYNE’s competitors. Although VYNE makes efforts to protect its trade secrets and other confidential information VYNE cannot be certain that all parties that gain access to VYNE’s proprietary information, or who may be involved in the development of VYNE’s intellectual property have entered into written confidentiality agreements, or that such agreements will be sufficiently protective, or that they will not be breached. Also, to the extent that VYNE’s employees, consultants or contractors use any intellectual property owned by others in their work for VYNE, disputes may arise as to the rights in any related or resulting know-how and inventions. Additionally, others may independently develop the same or substantially equivalent proprietary information and techniques or otherwise gain access to VYNE’s trade secrets and other confidential information. Any of the foregoing could deteriorate VYNE’s competitive advantages, undermine the trade secret and contractual protections afforded to VYNE’s confidential information and have material adverse effects on VYNE’s business. VYNE relies on information technology and access to the internet. Loss of material on servers or the cloud, disruptions and or breaches of cybersecurity could deteriorate VYNE’s competitive advantages, undermine the trade secret and contractual protections afforded to VYNE’s confidential information and have material adverse effects on VYNE’s business.

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Changes in U.S. or foreign patent law and practice could diminish the value of patents in general, thereby impairing VYNE’s ability to protect VYNE’s product candidates.

As is the case with other companies in the markets in which VYNE participates, VYNE’s success is heavily dependent on intellectual property, particularly patents. The strength of patents in the pharmaceutical field involves complex legal and scientific questions and moreover in the United States and in many foreign jurisdictions patent policy, practice and case law continues to evolve and change and the issuance, scope, validity, enforceability and commercial value of VYNE’s patent rights are highly uncertain. This uncertainty includes changes to the patent laws through one or more of legislative action to change statutory patent law, rule changes and practice directions issued by National Patent Offices, or court action that may reinterpret, limit or expand on existing law in ways affecting the scope or validity of granted patents and what may be claimed in pending applications. Particularly in recent years in the United States, there have been several major legislative developments and court decisions that have affected patent laws and how they are applied in significant ways and there may be more developments in the future that may weaken or undermine VYNE’s ability to obtain patents or to enforce VYNE’s existing and future patents. Additionally, new guidelines are issued by the USPTO and by the FDA from time to time which can impact patent practice in the pharmaceutical industry in significant ways. Similarly, changes in patent law and regulations in other countries or jurisdictions or changes in the governmental bodies that enforce them or changes in how the relevant governmental authority enforces patent laws or regulations may weaken VYNE’s ability to obtain new patents or to enforce patents that VYNE have licensed or that it may obtain in the future.

If VYNE infringes or is alleged to infringe or otherwise violate intellectual property rights of third parties, VYNE’s business could be harmed.

VYNE’s research and development activities may infringe or otherwise violate or be claimed to infringe or otherwise violate patents owned or controlled by other parties. Competitors in the field of topical and oral drugs have developed and may continue to develop large portfolios of patents and patent applications relating to VYNE’s business. In particular, there are patents and pending patent applications held by third parties that relate to new compounds that act as pan-BD BET inhibitors and also those that relate to BD2-selective BET inhibitors, as well as to methods of manufacture and methods of use for indications VYNE is pursuing, or are considering to pursue with VYNE’s repibresib and VYN202 product candidates. There may be granted patents with claims that could be asserted against VYNE in relation to such products or product candidates. There may also be granted patents held by third parties that may be infringed or otherwise violated by VYNE’s other product candidates and activities, and VYNE does not know whether or to what extent it may be infringing or otherwise violating third party patents. There may also be third party patent applications, some of which may not yet have been published, which if approved and granted as patents may be asserted against VYNE in relation to its product candidates or activities. Patent applications can take years to issue and there may be applications that are pending and in the course of prosecution claims may change or be added and there may be patents and claims of which VYNE is unaware that may later issue with claims that might be infringed by commercializing a product or product candidate. VYNE may fail to identify applications and granted patents that may be asserted against VYNE in relation to its product candidates or activities. Searches and analyses undertaken may miss or not uncover all potential and future threats. It should be noted in this regard that no search is completely exhaustive. For example, a relevant patent or published application could escape detection because of unusual terminology or use of terminology that is still evolving in developing technological fields. Also, databases used in the searches may not be entirely complete. These third parties could bring claims against VYNE that would cause it to incur substantial expenses and, if successful against it, could cause it to pay substantial damages and legal fees. These third parties could include non-practicing entities that have no relevant products or revenue. Further, if a patent infringement suit were brought against VYNE, it could be temporarily or permanently enjoined or otherwise forced to stop or delay research, development, manufacturing or sales of the product or product candidate that is the subject of the suit.

As a result of patent infringement claims, or to avoid potential claims, VYNE may choose or be required to seek licenses from third parties. These licenses may not be available on acceptable terms, or at all. Even if VYNE is able to obtain a license, the license would likely obligate VYNE to pay license fees or royalties or both and may limit it in other ways, and the rights granted to it might be nonexclusive, which could result in VYNE’s competitors gaining access to the same intellectual property, or such rights might be restrictive and limit VYNE’s present and future activities. Ultimately, VYNE or a licensee could be prevented from commercializing a product or be forced to cease some aspect of its business operations, if, as a result of actual or threatened patent infringement claims, VYNE is unable to enter into licenses on acceptable terms.

There has been and there currently is substantial litigation and other proceedings regarding patent and other intellectual property rights in the pharmaceutical industry. Such litigation can be very expensive, and the cost burden of intellectual property litigation may impact on VYNE’s other activities. In addition to possible infringement claims against VYNE, VYNE may become a party to other patent litigation and other proceedings, including interference, derivation, review, re-examination or other post-grant proceedings

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declared or granted by the USPTO and similar proceedings in foreign countries, regarding intellectual property rights with respect to VYNE’s current or any future products. In some jurisdictions, third party observations or pre-grant oppositions may be filed, for example in Europe, India and Israel. A third party may initially sometimes choose to submit exploratory observations or oppositions in one or more foreign jurisdictions prior to commencing proceedings in the United States, where the costs could be higher. The cost and burden to VYNE of any patent litigation or other proceeding, even if resolved in VYNE’s favor, could be substantial. Some of VYNE’s competitors may be able to sustain the costs of such litigation or proceedings more effectively than VYNE can because of their substantially greater financial resources. Patent litigation and other proceedings may also absorb significant management time. Uncertainties resulting from the initiation and continuation of patent litigation or other proceedings and their outcome could impair VYNE’s ability to compete in the marketplace and impose a substantial financial burden on VYNE, and may further have an adverse effect on its ability to raise funds to pursue research and development activities and clinical trials. The occurrence of any of the foregoing could have a material adverse effect on VYNE’s business, financial condition or results of operations.

Furthermore, several of VYNE’s employees were previously employed at universities or other pharmaceutical companies, including potential competitors. While VYNE takes steps to prevent its employees from using the proprietary information or know-how of others that is not in the public domain or that has not already been independently developed by VYNE earlier, it may be subject to claims that it or these employees have inadvertently or otherwise used or disclosed, confidential information, intellectual property, trade secrets or other proprietary information of any such employee’s former employer. Litigation may be necessary to defend against these claims and, even if VYNE is successful in defending itself, could result in substantial costs to VYNE or be distracting to its management. If VYNE does not succeed with respect to any such claims, in addition to paying monetary damages and possible ongoing royalties, VYNE may lose valuable intellectual property rights or personnel.

Obtaining and maintaining VYNE’s intellectual property protection, such as patent protection, depends on compliance with various procedural, document submission, fee payment and other requirements imposed by governmental agencies, such as patent agencies, and VYNE’s intellectual property protection, such as patent protection, could be reduced or eliminated for non-compliance with these requirements.

The USPTO and various foreign patent agencies require compliance with a number of procedural, documentary, fee payment and other provisions to maintain patent applications and issued patents. Noncompliance or late compliance with these requirements can result in abandonment or lapse of a patent or patent application, resulting in partial or complete loss of patent rights in the relevant jurisdiction. In such an event, competitors might be able to enter the market earlier than would otherwise have been the case. Similarly, compliance with relevant provisions is required to maintain trademark applications and registrations, while non-compliance can, likewise, result in loss of rights. In some circumstances, however, VYNE may allow intellectual property rights to become abandoned, such as, where they are no longer considered of interest.

VYNE instructs foreign agents including translation agencies to prepare and file applications in multiple jurisdictions. If an agent omitted to file the patent application and where appropriate the translation timely in accordance with the national provisions or failed to translate the application accurately and or introduced errors into the translation VYNE may suffer loss of rights and it may not discover this until after the filing deadline has passed.

If VYNE is unable to secure trademark registrations, secure appropriate domain names and protect its trademarks or trade dress from infringement, VYNE’s business prospects may be harmed.

VYNE owns trademarks that identify “VYNE” and “VYNE Therapeutics” and have submitted applications to register these trademarks in the United States and in various other jurisdictions. Similarly, VYNE owns trademarks that represent VYNE’s leaf logo which can be and is used with the “VYNE” and “VYNE Therapeutics” trademarks and VYNE’s VYNE identity and have submitted applications to register these leaf trademarks in the United States and in some other jurisdictions. VYNE has selected the trademark InhiBET for use in relation to its BET inhibitor programs and VYNE has applied to register the trademark in Israel and the United States. VYNE has not yet selected or submitted trademark applications for a proposed commercial trade name for any of its product candidates or activities in the United States or elsewhere and failure to do so and secure registrations could adversely affect VYNE’s business.

Applications for trademarks may be rejected during prosecution and VYNE may be unable to overcome such proceedings or it may have to narrow or limit the scope of the applications or rely on a lower level of protection provided by common law unregistered trademark rights, if any. Opposition or cancellation proceedings may be filed against VYNE’s trademarks, which may not survive such proceedings or VYNE may have to narrow or limit their scope.

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In the United States, the FDA evaluates and must approve any trademark VYNE proposes to use with products for which it seeks regulatory approval regardless of whether it has registered it, or applied to register it, as a trademark. The FDA review will include an evaluation of potential for confusion with other product names. Selecting a product trademark can be an expensive process. If the FDA objects to proposed trademarks this could delay regulatory approval and VYNE may be required to expend significant resources in an effort to identify suitable substitutes that would qualify as a registerable trademark, not infringe any existing third party trademark rights and be acceptable to the FDA.

Although VYNE takes steps to monitor the possible infringement or misuse of VYNE’s trademarks, it is possible that third parties may infringe, dilute or otherwise violate VYNE’s trademark rights. Any unauthorized use of VYNE’s trademarks could harm VYNE’s reputation or commercial interests. In addition, VYNE’s enforcement against third party infringers or violators may be unduly expensive and time-consuming, and the outcome may be an inadequate remedy.

Additionally, VYNE has rights in certain domain names associated with its business. If others seek to use domain names closely similar and VYNE is not successful in asserting and protecting its rights it could adversely affect VYNE’s business.

VYNE may become involved in lawsuits to protect or enforce its patents or other intellectual property or the patents of VYNE’s licensors, which could be expensive and time-consuming.

Competitors may infringe VYNE’s intellectual property, including VYNE’s patents or the patents of VYNE’s licensors. As a result, VYNE may be required to file infringement claims to stop third party infringement or unauthorized use. This can be expensive and burdensome, particularly for a company of VYNE’s size, as well as time-consuming. In addition, in an infringement proceeding, a court may decide that a patent or certain patent claims of VYNE are not valid, or are unenforceable, or may refuse to stop the other party or parties from using the technology or method at issue on the grounds that VYNE’s patent claims do not cover its or their technology or method or that the factors necessary to grant an injunction against an infringer are not satisfied.

An adverse determination of any litigation or other proceedings could put one or more of VYNE’s patents at risk of being invalidated or interpreted narrowly and could put VYNE’s patent applications at risk of not issuing.

Interference, derivation review, or other proceedings brought at the USPTO may be necessary to determine the priority or patentability of inventions with respect to VYNE’s patent applications or those of VYNE’s licensors or licensees. Litigation or USPTO proceedings brought by VYNE may fail or may be invoked against VYNE by third parties. Even if VYNE is successful in any proceedings (domestic or foreign, litigation or USPTO or foreign patent office or other proceedings) they may result in substantial costs and distraction to VYNE’s management. Moreover, proceedings may be appealed and obtaining a final resolution can take a long time and substantial resources. VYNE may not be able, alone or with its licensors or licensees, to prevent misappropriation of VYNE’s proprietary rights, particularly in countries where the laws may not protect such rights as fully as in the United States. Furthermore, because of the substantial amount and extent of discovery required in connection with intellectual property litigation or other proceedings, there is a risk that some of VYNE’s confidential information could be compromised by disclosure during this type of litigation or proceedings. In addition, during the course of this kind of litigation or proceedings, there could be public announcements of the results of hearings, motions or other interim proceedings or developments or public access to related documents. If investors perceive these results to be negative, the market price for VYNE Common Stock could be significantly harmed and this may be so even if the results are not considered material.

VYNE may not obtain intellectual property rights or otherwise be able to protect VYNE’s intellectual property rights throughout the world.

Filing, prosecuting and defending patents on product candidates in all or most countries throughout the world would be prohibitively expensive. VYNE primarily files patent applications in the United States and may file in some other selected jurisdictions on a case-by-case basis. In general, VYNE may on a case-by- case basis file national applications more narrowly in respect of patent applications directed to compositions of matter and methods of treatment than for those concerning new chemical entities. As a result, VYNE’s intellectual property rights in countries outside the United States are generally significantly less extensive than those in the United States. In addition, the laws of some foreign countries and jurisdictions, particularly of certain developing countries and jurisdictions, do not protect intellectual property rights to the same extent as federal and state laws in the United States, and these countries and jurisdictions may limit the scope of what can be claimed, and in some cases may even force VYNE to grant a compulsory license to competitors or other third parties. Consequently, VYNE may not be able to prevent third parties from practicing its inventions outside the United States, or from selling or importing products made using its inventions in and into the United States or other jurisdictions. Competitors may seek to exploit VYNE’s technologies in jurisdictions where VYNE has a

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patent application filed, for example, as it has not been allowed or if allowed where they intend to challenge one or more granted claims. Competitors may use VYNE’s technologies in jurisdictions where VYNE has not sought or obtained patent protection to develop their own products and further, may export otherwise infringing products to territories where VYNE has patent protection, but protection and enforcement is not as strong or effective as that in the United States. These products may compete with VYNE’s product candidates, if approved, and VYNE’s patents or other intellectual property rights may not be effective or sufficient to prevent them from competing. Moreover, competitors or others may raise legal challenges to VYNE’s intellectual property rights or may infringe upon VYNE’s intellectual property rights, including through means that may be difficult to prevent or detect.

Many companies have encountered significant problems in protecting and defending intellectual property rights in foreign jurisdictions. In some foreign jurisdictions the patent system, for example, may not allow certain types of claims that are acceptable in the United States or may only accept claims of a narrower scope. The legal systems of certain countries, particularly certain developing countries, do not favor the enforcement of patents and other intellectual property protection, especially those relating to pharmaceuticals and methods of treatment, which could make it difficult for VYNE to stop the infringement of its patents or of other intellectual property protection, misappropriation of intellectual property rights, or marketing of competing products in violation of VYNE’s proprietary rights generally. For example, some foreign countries have compulsory licensing laws under which a patent owner must grant licenses to third parties. In addition, some countries limit the enforceability of patents against third parties, including government agencies or government contractors. In such countries, patents may provide limited or no benefit. Proceedings to enforce VYNE’s patent rights in foreign jurisdictions could result in substantial costs and divert VYNE’s efforts and attention from other aspects of VYNE’s business, could put VYNE’s patents at risk of being invalidated or interpreted narrowly and VYNE’s patent applications at risk of not issuing and could provoke third parties to assert claims or issue proceedings against VYNE. VYNE may not prevail in any lawsuits that it initiates, and the damages or other remedies awarded, if any, may not be commercially meaningful. Further, third parties may prevail in their claims against VYNE, which could potentially result in the award of injunctions or substantial damages against it. Accordingly, VYNE’s efforts to enforce its intellectual property rights around the world may be inadequate to obtain a significant commercial advantage from the intellectual property that it develops or licenses.

In addition, VYNE’s ability to protect and enforce its intellectual property rights may be adversely affected by unforeseen changes in domestic and foreign intellectual property laws and practice.

VYNE may not be able to enforce covenants not to compete under applicable employment laws.

VYNE generally enters into non-competition agreements as part of its employment agreements with its employees. These agreements generally prohibit VYNE’s employees, if they cease working for VYNE, from competing directly with it or working for its competitors or clients for a limited period. VYNE may be unable to enforce these agreements under the laws of the jurisdictions in which VYNE’s employees work and it may be difficult for VYNE to restrict its competitors from benefiting from the expertise VYNE’s former employees or consultants developed while working for VYNE. Post-Merger organizational changes in connection with VYNE’s business combination with Yarrow may add to the risk of employees departing to work for VYNE’s competitors in jurisdictions where covenants not to compete are difficult to enforce.

Risks Related to the Ownership of VYNE’s Common Stock

The trading price of the shares of VYNE Common Stock is volatile, and stockholders could incur substantial losses.

VYNE’s stock price is volatile. The stock market in general, and the market for biopharmaceutical companies in particular, have experienced extreme volatility that has often been unrelated to the operating performance of particular companies. For example, VYNE’s stock price, and the stock price of many other public companies, experienced a period of high volatility in recent years. Such volatility resulted in rapid and substantial increases and decreases in VYNE’s stock price that may or may not be related to VYNE’s operating performance or prospects. As a result of this volatility, stockholders may not be able to sell their common stock at or above the price paid for the shares. In addition, in the past, stockholders have initiated class action lawsuits against pharmaceutical and biotechnology companies, including VYNE, following periods of volatility in the market prices of these companies’ common stock. If VYNE is subject to future lawsuits it would be subject to additional risks as described in “VYNE may become subject to lawsuits or investigations that could have a material adverse impact on its business, results of operations and financial condition” above. The market price for VYNE Common Stock may be influenced by many factors, including:

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Consequently, the current market price of VYNE Common Stock may not be indicative of future market prices, and VYNE may be unable to sustain or increase the value of an investment in VYNE Common Stock.

Provisions in VYNE’s corporate charter documents and under Delaware law may prevent or frustrate attempts by VYNE’s stockholders to change VYNE’s management and hinder efforts to acquire a controlling interest in VYNE, and the market price of VYNE Common Stock may be lower as a result.

The VYNE Charter and the VYNE Bylaws contain provisions that could delay or prevent changes in control or changes in VYNE’s management without the consent of the VYNE board of directors. These provisions include the following:

In addition, these provisions would apply even if VYNE were to receive an offer that some stockholders may consider beneficial.

VYNE is also subject to the anti-takeover provisions contained in Section 203 of the Delaware General Corporation Law. Under Section 203, a corporation may not, in general, engage in a business combination with any holder of 15% or more of its capital stock unless the holder has held the stock for three years or, among other exceptions, the board of directors has approved the transaction.

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Claims for indemnification by VYNE’s directors and officers may reduce VYNE’s available funds to satisfy successful third-party claims against it and may reduce the amount of money available to VYNE.

VYNEs’ directors and executive officers may be subject to litigation for a variety of claims or disputes. The VYNE Charter and the VYNE Bylaws provide that VYNE will indemnify its directors and officers, in each case to the fullest extent permitted by Delaware law.

In addition, as permitted by Section 145 of the Delaware General Corporation Law, the VYNE Bylaws and VYNE’s indemnification agreements that it has entered into with its directors and officers provide that:

While VYNE maintains directors’ and officers’ liability insurance, such insurance may not be adequate to cover all liabilities that it may incur, which may reduce VYNE’s available funds to satisfy third-party claims and could harm VYNE’s business, results of operations, and financial condition. Further, a stockholder’s investment may be harmed to the extent that VYNE pays the costs of settlement and damage awards against VYNE’s directors and executive officers as required by these indemnification provisions.

The VYNE Charter and the VYNE Bylaws contain exclusive forum selection clauses, which could limit VYNE’s stockholders’ ability to obtain a favorable judicial forum for disputes with VYNE or its directors, officers or employees.

The VYNE Charter provides that the Court of Chancery of the State of Delaware is the exclusive forum for any derivative action or proceeding brought on VYNE’s behalf, any action asserting a breach of fiduciary duty, any action asserting a claim against VYNE arising pursuant to the Delaware General Corporation Law, the VYNE Charter or the VYNE Bylaws, any action to interpret, apply, enforce, or determine the validity of the VYNE Charter or the VYNE Bylaws, or any action asserting a claim against VYNE that is governed by the internal affairs doctrine. In addition, the VYNE Bylaws provide that unless VYNE consents in writing to the selection of an alternative forum, the federal district courts of the United States is the exclusive forum for resolving any complaint asserting a cause of action arising under the Securities Act of 1933, as amended (the “Securities Act”), against VYNE, its officers, directors, employees or underwriters. These choice of forum provisions may limit a stockholder’s ability to bring a claim in a judicial forum that it finds favorable for disputes with VYNE or its directors, officers or other employees, which may discourage such lawsuits against VYNE and its directors, officers and other employees.

Alternatively, if a court were to find the choice of forum provision contained in the VYNE Charter or the VYNE Bylaws to be inapplicable or unenforceable in an action, VYNE may incur additional costs associated with resolving such action in other jurisdictions, which could adversely affect VYNE’s business and financial condition.

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VYNE is eligible to report as a “smaller reporting company,” and as a result of the reduced reporting requirements applicable to such companies, VYNE’s securities may be less attractive to investors.

VYNE is eligible to report as a smaller reporting company. For as long as VYNE continues to be eligible to report as a “smaller reporting company,” VYNE may take advantage of exemptions from various reporting requirements that are applicable to other public companies that are not “smaller reporting companies,” including not being required to comply with the auditor attestation requirements in the assessment of VYNE’s internal control over financial reporting, as well as reduced disclosure obligations regarding executive compensation in VYNE’s periodic reports, proxy statements and registration statements.

VYNE may take advantage of these reporting exemptions until it is no longer a smaller reporting company. VYNE will remain a smaller reporting company until the last day of any fiscal year for so long as either (1) the market value of shares of VYNE Common Stock held by non-affiliates does not equal or exceed $250.0 million as of the prior June 30th, or (2) VYNE’s annual revenues did not equal or exceed $100.0 million during such completed fiscal year and the market value of shares of VYNE Common Stock held by non-affiliates did not equal or exceed $700.0 million as of the prior June 30th.

VYNE cannot predict if investors will find VYNE Common Stock less attractive because it will rely on these exemptions. If some investors find VYNE’s securities less attractive because it relies on any of these exemptions, there may be a less active trading market for VYNE’s securities and the price of VYNE’s securities may be more volatile.

General Risk Factors

An active public market for VYNE Common Stock may not be sustained.

Although VYNE Common Stock is quoted on Nasdaq, an active trading market for VYNE Common Stock may not be sustained. The lack of an active market may impair the ability of holders of VYNE Common Stock to sell their shares at the time they wish to sell them or at a price that they consider reasonable. The lack of an active market may also reduce the fair market value of VYNE Common Stock, and may cause the trading price of VYNE Common Stock to be more volatile. The lack of an active market may contribute to volatility of VYNE’s stock price and impair VYNE’s ability to raise capital.

If equity research analysts do not publish research or reports, or publish unfavorable research or reports, about VYNE, its business or its market, its stock price and trading volume could decline.

The trading market for VYNE Common Stock may be influenced by the research and reports that equity research analysts publish about VYNE and its business. VYNE does not have any control over the analysts, or the content and opinions included in their reports. The price of VYNE’s stock could decline if one or more equity research analysts downgrade VYNE’s stock or issue other unfavorable commentary or research. If one or more equity research analysts cease coverage of VYNE’s company or fail to publish reports on VYNE regularly, demand for VYNE’s stock could decrease, which in turn could cause VYNE’s stock price or trading volume to decline. If VYNE’s operating results fail to meet the forecast of analysts, VYNE’s stock price will likely decline.

Sales of a substantial number of shares of VYNE Common Stock by VYNE’s existing stockholders in the public market could cause VYNE’s stock price to fall.

Sales of a substantial number of shares of VYNE Common Stock in the public market could occur at any time. These sales, or the perception in the market that VYNE’s directors, officers or holders of a large number of shares intend to sell shares, could reduce the market price of VYNE Common Stock. Moreover, certain holders of shares of VYNE Common Stock have rights, subject to certain conditions, to require VYNE to file registration statements covering their shares or to include their shares in registration statements that VYNE may file for itself or other stockholders. VYNE has registered and intends to continue to register all shares of common stock that it may issue under its equity compensation plans. Once VYNE registers these shares, they can be freely sold in the public market upon issuance, subject to volume limitations applicable to affiliates.

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Except for the Cash Dividend in connection with the Merger, VYNE does not currently intend to pay dividends on VYNE Common Stock, and, consequently, VYNE’s stockholders’ ability to achieve a return on their investment will depend on appreciation in the price of VYNE Common Stock.

Except for the Cash Dividend in connection with the Merger, VYNE does not currently intend to pay any cash dividends on VYNE Common Stock for the foreseeable future. VYNE currently intends to invest its future earnings, if any, to fund its growth. Therefore, stockholders are not likely to receive any dividends on their common stock for the foreseeable future. Since VYNE does not intend to pay dividends, other than the Cash Dividend, stockholders’ ability to receive a return on their investment will depend on any future appreciation in the market value of VYNE Common Stock. VYNE Common Stock may not appreciate or even maintain the price at which VYNE’s holders have purchased it.

If VYNE fails to maintain proper and effective internal controls, VYNE’s ability to produce accurate financial statements on a timely basis could be impaired.

VYNE is subject to the reporting requirements of the Exchange Act of 1934, as amended (the “Exchange Act”), the Sarbanes-Oxley Act and the rules and regulations of Nasdaq. The Sarbanes-Oxley Act requires, among other things, that VYNE maintain effective disclosure controls and procedures and internal control over financial reporting. VYNE must perform system and process evaluation and testing of VYNE’s internal control over financial reporting to allow management to report on the effectiveness of VYNE’s internal control over financial reporting in VYNE’s Form 10-K filing each year, as required by Section 404 of the Sarbanes-Oxley Act. This requires that VYNE incur substantial additional professional fees and internal costs within VYNE’s accounting and finance functions and that VYNE expends significant management efforts.

VYNE may identify weaknesses in its system of internal financial and accounting controls and procedures that could result in a material misstatement of VYNE’s financial statements. VYNE’s internal control over financial reporting will not prevent or detect all errors and all fraud. A control system, no matter how well designed and operated, can provide only reasonable, not absolute, assurance that the control system’s objectives will be met. Because of the inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that misstatements due to error or fraud will not occur or that all control issues and instances of fraud will be detected.

If VYNE is not able to comply with the requirements of Section 404 of the Sarbanes-Oxley Act in a timely manner, or if VYNE is unable to maintain proper and effective internal controls, VYNE may not be able to produce timely and accurate financial statements. If that were to happen, the market price of VYNE’s stock could decline, and VYNE could be subject to sanctions or investigations by the stock exchange on which VYNE Common Stock is listed, the SEC, or other regulatory authorities.

VYNE incurs significant costs and demands upon management as a result of being a public company.

As a public company listed in the United States, VYNE incurs significant additional legal, accounting and other costs, as compared to the costs it incurred as a private company. These additional costs could negatively affect VYNE’s financial results. In addition, changing laws, regulations and standards relating to corporate governance and public disclosure, including regulations implemented by the SEC and Nasdaq, may increase legal and financial compliance costs and make some activities more time-consuming. These laws, regulations and standards are subject to varying interpretations and, as a result, their application in practice may evolve over time as new guidance is provided by regulatory and governing bodies. VYNE may experience significantly increased general and administrative expenses and a diversion of management’s time and attention from its primary business operations if VYNE is required to invest significant resources to comply with new and evolving laws, regulations and standards. If notwithstanding VYNE’s efforts to comply with new laws, regulations and standards, it fails to comply, regulatory authorities may initiate legal proceedings against VYNE and its business may be harmed.

Failure to comply with these rules might also make it more difficult for VYNE to obtain some types of insurance, including director and officer liability insurance, and VYNE might be forced to accept reduced policy limits and coverage or incur substantially higher costs to obtain the same or similar coverage. The impact of these events could also make it more difficult for VYNE to attract and retain qualified persons to serve on the VYNE board of directors, on committees of the VYNE board of directors or as members of senior management.

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VYNE is not currently in compliance with the continued listing requirement for the Nasdaq Capital Market to maintain a minimum closing bid price of $1.00 dollar per share, as set forth in Nasdaq Listing Rule 5550(a)(2), because the closing bid price of VYNE Common Stock was below $1.00 per share for 30 consecutive business days. If VYNE does not regain compliance and continue to meet the continued listing requirements, VYNE Common Stock may be delisted from the Nasdaq Capital Market, which could affect the market price and liquidity for VYNE Common Stock and reduce VYNE’s ability to raise additional capital and the Merger may not be consummated.

The VYNE Common Stock is currently listed on the Nasdaq Capital Market. On September 11, 2025, VYNE received notice from Nasdaq that VYNE is not in compliance with the requirement to maintain a minimum closing bid price of $1.00 per share, as set forth in Nasdaq Listing Rule 5550(a)(2), because the closing bid price of the VYNE Common Stock was below $1.00 per share for 30 consecutive business days. Although the notification does not impact the listing of the VYNE Common Stock on the Nasdaq Capital Market at this time, VYNE had until March 10, 2026 to regain compliance with the minimum bid price requirement. On March 11, 2026, VYNE received a letter (the “Extension Notice”) from Nasdaq notifying VYNE that its request for an extension to regain compliance with the minimum bid price requirement has been granted, and VYNE has an additional 180 calendar days, or until September 7, 2026, to regain compliance with the minimum bid price requirement. Nasdaq’s determination was based on VYNE meeting the continued listing requirement for market value of publicly held shares and all other applicable requirements for initial listing on the Nasdaq Capital Market with the exception of the bid price requirement, and VYNE’s written notice of its intention to cure the deficiency during the second compliance period by effecting a reverse stock split, if necessary. The Extension Notice has no immediate effect on the listing or trading of VYNE’s common stock on The Nasdaq Capital Market and, at this time, VYNE’s common stock will continue to trade on The Nasdaq Capital Market under the symbol “VYNE.”

VYNE is considering all available options to regain compliance with the listing rule. However, there can be no assurance that VYNE will be able to regain compliance with the rule or will otherwise be in compliance with other Nasdaq listing criteria. If VYNE fails to regain compliance by September 7, 2026, then Nasdaq will notify VYNE that VYNE Common Stock is subject to delisting.

The perception among investors that VYNE is at a heightened risk of delisting could negatively affect the market price and trading volume of the VYNE Common Stock. If the VYNE Common Stock is delisted from Nasdaq, the delisting could: substantially decrease trading in the VYNE Common Stock; adversely affect the market liquidity of the VYNE Common Stock as a result of the loss of market efficiencies associated with Nasdaq and the loss of federal preemption of state securities laws; adversely affect VYNE’s ability to issue additional securities or obtain additional financing in the future on acceptable terms, if at all; result in the potential loss of confidence by investors, suppliers, partners, and employees and fewer business development opportunities; and result in limited news and analyst coverage. Additionally, the market price of the VYNE Common Stock may decline further, and stockholders may lose some or all of their investment.

VYNE is subject to risks related to climate change in the long term.

VYNE is subject to transitional and physical risks related to climate change. Transitional risks include, for example, a disorderly global transition away from fossil fuels that may result in increased energy prices; customer preference for low or no-carbon products; stakeholder pressure to decarbonize assets; or new legal or regulatory requirements that result in new or expanded carbon pricing, taxes, restrictions on greenhouse gas emissions, and increased greenhouse gas disclosure and transparency. These risks could increase operating costs, including the cost of VYNE’s electricity and energy use, or other compliance costs. Physical risks to VYNE’s operations include water stress and drought; flooding and storm surge; wildfires; extreme temperatures and storms, which could impact trials, increase costs, or disrupt supply chains. VYNE’s supply chain is likely subject to these same transitional and physical risks and would likely pass along any increased costs to VYNE. VYNE does not anticipate that these risks will have a material financial impact to the company in the near term.

Governmental authorities, non-governmental organizations, customers, investors, employees, and other stakeholders are increasingly sensitive to environmental, social and governance (“ESG”) matters, such as equitable access to medicines and vaccines, product quality and safety, diversity, equity and inclusion, environmental stewardship, support for local communities, value chain environmental and social due diligence, corporate governance and transparency, and addressing human capital factors in VYNE’s operations. In addition, governments and the public expect companies to report on VYNE’s business practices with respect to human rights, responsible sourcing and environmental impact, as well as the actions of VYNE’s third-party contractors and suppliers around the world. This focus on ESG matters may lead to new expectations or requirements that could result in increased costs associated with research and development of VYNE’s products. VYNE’s ability to compete could also be affected by changing customer preferences and requirements, such as growing demand for companies to establish validated Net Zero emissions targets or offer more sustainable products. If VYNE does not meet, or are perceived not to meet, stakeholder expectations in key ESG areas, it risks

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negative stakeholder reaction, including from proxy advisory services, as well as damage to VYNE’s brand and reputation, or other negative impacts on VYNE’s business and operations. While VYNE monitors ESG matters, it cannot be certain that it will manage such matters successfully, or that it will successfully meet the expectations of investors, employees, consumers, governments and other stakeholders.

Risks Related to Yarrow

Risks Related to Yarrow’s Limited Operating History, Financial Position and Capital Requirements

Yarrow is a clinical stage biotechnology company with a limited operating history on which to assess its business; Yarrow has not completed any clinical trials, and it has no products approved for commercial sale, which may make it difficult to evaluate its current business and likelihood of success and viability.

Yarrow is a clinical stage biotechnology company with limited operating history. Since its inception, Yarrow has incurred operating losses with no corresponding revenue and has utilized substantially all of its resources to identify, license and develop its lead product candidate, organize and staff its company and provide other general and administrative support for its operations. Yarrow has no significant experience as a company in initiating, conducting or completing preclinical studies or clinical trials. In part because of this lack of experience, Yarrow cannot be certain that its clinical trials and any future preclinical studies will begin or be completed on time, if at all. In addition, Yarrow has not yet demonstrated an ability to obtain regulatory approvals, manufacture a commercial-scale product or arrange for a third party to do so on its behalf, or conduct sales, marketing and distribution activities necessary for successful product commercialization. Consequently, any predictions about Yarrow’s future success or viability may not be as accurate as they could be if Yarrow had a longer operating history.

In addition, as Yarrow’s business grows, Yarrow may encounter unforeseen expenses, restrictions, difficulties, complications, delays and other known and unknown factors. Yarrow will need to transition at some point from a company with an early-stage clinical development focus to a company capable of supporting larger scale clinical trials and eventually commercial activities. Yarrow may not be successful in such a transition.

Even if the Merger and the Yarrow Pre-Closing Financing are successful, Yarrow will require substantial additional capital to finance its operations in the future. If Yarrow is unable to raise such capital when needed, or on acceptable terms, Yarrow may be forced to delay, reduce and/or discontinue development of YB-101 or its future commercialization efforts.

Developing biotechnology products is a long, time-consuming, expensive and uncertain process that takes years to complete. Yarrow expects its expenses to increase in connection with its ongoing activities, particularly as Yarrow conducts clinical trials of, and seeks regulatory approval for YB-101, conducts any future preclinical studies, advances discovery efforts with respect to future product candidates, and advances any future programs and product candidates that Yarrow may license. Even if one or more of the product candidates that Yarrow develops is approved for commercial sale, Yarrow anticipates incurring significant costs associated with sales, marketing, manufacturing and distribution activities to launch any such product. Yarrow’s expenses could increase beyond expectations if Yarrow is required by the FDA or other regulatory agencies to perform preclinical studies or clinical trials in addition to or more expansive than those that Yarrow currently anticipates. Because the design and outcome of Yarrow’s planned and anticipated clinical trials are highly uncertain, Yarrow cannot reasonably estimate the actual amount of funding that will be necessary to successfully complete the development and commercialization of any product candidate Yarrow develops. Yarrow’s future capital requirements depend on many factors, including but not limited to:

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As a result, Yarrow will require substantial additional funding to continue its operations. As of December 31, 2025, Yarrow had $100.0 million ($30.0 million after the $70 million upfront payment under the GenSci License Agreement) of cash, cash equivalents and short-term investments. Yarrow expects that its existing cash, cash equivalents and short-term investments, combined with the gross proceeds of approximately $100.0 million from the Yarrow Pre-Closing Financing, will be sufficient to fund the Combined Company’s operating expenses and capital expenditure requirements into 2028. Even if the Merger and the Yarrow Pre-Closing Financing are successful, Yarrow will still need to raise additional capital to continue to fund its operations in the future. If Yarrow is unable to raise additional capital when needed, that could raise substantial doubt about Yarrow’s ability to continue as a going concern.

Yarrow may be required to seek additional funds sooner than planned through public or private equity offerings, debt financings, collaborations and licensing arrangements or other sources, and adequate additional financing may not be available to Yarrow on acceptable terms, or at all. Such financing may dilute Yarrow’s stockholders or the failure to obtain such financing may restrict Yarrow’s operating activities. Any additional fundraising efforts may divert Yarrow’s management from their day-to-day activities, which may adversely affect Yarrow’s business. To the extent that Yarrow raises additional capital through the sale of equity or convertible debt securities, the ownership interest of Yarrow’s stockholders will be diluted, and the terms may include liquidation or other preferences and anti-dilution protections that adversely affect the rights of Yarrow’s stockholders. Debt financing may result in the imposition of debt covenants, increased fixed payment obligations or other restrictions that may affect Yarrow’s business. If Yarrow raises additional funds through upfront payments or milestone payments pursuant to current or future collaborations with third parties, Yarrow may have to relinquish valuable rights to Yarrow’s product candidates, or grant licenses on terms that are not favorable to Yarrow. Yarrow’s ability to raise additional capital may be adversely impacted by global macroeconomic conditions and volatility in the credit and financial markets in the United States and worldwide. Yarrow’s failure to raise capital as and when needed or on acceptable terms would have a negative impact on Yarrow’s financial condition and Yarrow’s ability to pursue its business strategy, and Yarrow may have to delay, reduce the scope of, suspend or eliminate one or more of its product candidates, clinical trials or future commercialization efforts or cease Yarrow’s operations.

Yarrow expects to continue to incur losses for the foreseeable future and may not be able to achieve or sustain profitability in the future. Yarrow has no products approved for sale, has not generated any revenue from its product candidates and may never generate revenue or become profitable.

Investment in biotechnology product development is a highly speculative undertaking and entails substantial upfront capital expenditures and significant risks that any product candidate will fail to demonstrate adequate efficacy or an acceptable safety profile, gain regulatory approval and become commercially viable. Yarrow has no products approved for commercial sale, has not generated any revenue from product sales to date, and continues to incur significant research and development and other expenses related to Yarrow’s ongoing operations. Yarrow does not expect to generate product revenue unless or until Yarrow successfully completes preclinical and clinical development and obtains regulatory approval of, and then successfully commercializes, at least one of its product candidates.

Yarrow may never succeed in these activities and, even if it does, may never generate revenues that are significant or large enough to achieve profitability. If Yarrow is unable to raise sufficient additional capital to advance a product candidate to

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commercialization or generate sufficient revenue through the sale of any approved products, Yarrow may be unable to continue operations without additional funding.

Yarrow incurred significant net losses in each period since it commenced operations in October 2025. Yarrow generated net losses of $71.0 million for the period from October 3, 2025 (inception) to December 31, 2025. As of December 31, 2025, Yarrow had an accumulated deficit of $71.0 million. Yarrow expects to continue to incur losses for the foreseeable future. Yarrow’s operating expenses and net losses may fluctuate significantly from quarter to quarter and year to year. Yarrow anticipates that its expenses will increase substantially if and as Yarrow:

In addition, Yarrow’s expenses will increase if, among other things, it is required by the FDA or other regulatory authorities to perform clinical trials or studies in addition to, or different than, those that Yarrow currently anticipates, there are any delays in completing Yarrow’s clinical trials or the development of any of its product candidates, or there are any third-party challenges to Yarrow’s intellectual property or Yarrow needs to defend against any intellectual property-related claim.

Even if Yarrow obtains regulatory approval for, and is successful in commercializing, one or more of Yarrow’s product candidates, Yarrow expects to incur substantial additional research and development and other expenditures to develop and market additional product candidates and/or to expand the approved indications of any marketed product. Yarrow may encounter unforeseen expenses, difficulties, complications, delays and other unknown factors that may adversely affect its business. The size of Yarrow’s future net losses will depend, in part, on the rate of future growth of Yarrow’s expenses and its ability to generate revenue.

Yarrow’s failure to become profitable would decrease its value and could impair its ability to raise capital, maintain its research and development efforts, expand its business and/or continue its operations. A decline in the value of the Combined Company’s stock could also cause stockholders to lose all or part of their investment.

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Risks Related to Yarrow’s Discovery, Development and Commercialization

Yarrow faces competition from entities that have developed or may develop product candidates for the diseases addressed by Yarrow’s product candidates.

The development and commercialization of drugs is highly competitive, particularly in the treatment of Graves’ disease (“GD”) and thyroid eye disease (“TED”). YB-101, if approved, will face significant competition and Yarrow’s failure to effectively compete may prevent Yarrow from achieving significant market penetration. Yarrow competes with a variety of multinational biopharmaceutical companies, specialized biotechnology companies and emerging biotechnology companies, including Immunovant, Inc., Biohaven Ltd., Amgen, Inc. (“Amgen”), which acquired TEPEZZA^® from Horizon Therapeutics plc in October 2023, Alumis Inc., Argenx SE, Biohaven, Sanofi, Merida Biosciences, H. Lundbeck A/S, Lassen Therapeutics, Roche, Sling Therapeutics, Inc., Novartis AG (which acquired Tourmaline Bio, Inc. in October 2025), and Viridian Therapeutics, Inc. as well as, academic institutions, governmental agencies, and public and private research institutions, among others. Many of the companies with which Yarrow is currently competing or will compete against in the future have significantly greater financial resources and expertise in research and development, manufacturing, preclinical testing, conducting clinical trials, obtaining regulatory approvals, and regulatory approved products than Yarrow does, and are further along in the clinical development and/or commercialization process. Mergers and acquisitions in the pharmaceutical and biotechnology industry may result in even more resources being concentrated among a smaller number of Yarrow’s competitors. For example, in May 2025, Alumis Inc. and ACELYRIN, INC. completed a merger transaction and the combined company is advancing a subcutaneously delivered anti-IGF-1R antibody for the treatment of TED. Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies. These competitors also compete with Yarrow in recruiting and retaining qualified scientific and management personnel, establishing clinical trial sites, raising capital, patient registration for clinical trials, establishing and defending rights to intellectual property, as well as in acquiring technologies complementary to, or necessary for, Yarrow’s product candidates.

Yarrow’s competitors have developed or are developing, and may in the future develop, product candidates or products competitive with Yarrow’s product candidates. Competitive therapeutic treatments include those that have already been approved and accepted by the medical community and any potential new treatments, including those currently under clinical development. Yarrow’s success will depend partially on its ability to develop and commercialize products that have a competitive safety, efficacy, dosing and/or presentation profile. Yarrow’s commercial opportunity and success will be reduced or eliminated if competing products are safer, more effective, have a more attractive dosing profile or presentation or are less expensive than the products Yarrow develops, or if Yarrow’s competitors develop competing products or biosimilars that enter the market more quickly than Yarrow does and are able to gain market acceptance. Conversely, the lack of commercial success of other competing therapies may raise concerns about the financial viability of Yarrow’s product candidates.

In addition, because of the competitive landscape for thyroid autoimmune diseases, including GD and TED, Yarrow may also face competition for establishing trial sites and clinical trial enrollment. Patient enrollment will depend on many factors, including if potential clinical trial patients choose to undergo treatment with approved products or enroll in competitors’ ongoing clinical trials for product candidates that are under development for the same indications as Yarrow’s product candidates. An increase in the number of approved products for the indications Yarrow is targeting with its product candidates will likely further exacerbate this competition. Yarrow’s inability to enroll a sufficient number of patients could, among other impacts, delay Yarrow’s development timeline, which may further harm Yarrow’s competitive position.

YB-101 is in the clinical stages of development and YB-101 and Yarrow’s future product candidates may fail in development or suffer delays that materially and adversely affect Yarrow’s viability. If Yarrow or its current or future collaborators are unable to complete development of or commercialize Yarrow’s product candidates, or experience significant delays in doing so, Yarrow’s business will be materially harmed.

Yarrow has no commercially approved products. YB-101 is in the clinical stages of development, and Yarrow has not completed any clinical trials. As a result, Yarrow expects it will be many years before Yarrow commercializes any product candidate, if ever. Yarrow’s ability to achieve and sustain profitability depends on obtaining regulatory approvals for, and successfully commercializing, Yarrow’s product candidates, either alone or with third parties, and Yarrow cannot guarantee you that it will ever obtain regulatory approval for any of its product candidates. Yarrow has not yet demonstrated its ability to complete any clinical trials, obtain regulatory approvals, manufacture a commercial-scale product or arrange for a third party to do so on Yarrow’s behalf, or conduct sales and marketing activities necessary for successful product commercialization. Before obtaining regulatory approval for the commercial distribution of any product candidate, Yarrow or an existing or future collaborator must conduct extensive preclinical tests and clinical trials to demonstrate the safety and efficacy in humans of the product candidate.

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Yarrow or its collaborators may experience delays in initiating or completing preclinical studies or clinical trials. Yarrow or its collaborators also may experience numerous unforeseen events during, or as a result of, any future preclinical studies or clinical trials that Yarrow could conduct that could delay or prevent Yarrow’s ability to receive regulatory approval or commercialize its product candidates, including:

Commencing clinical trials in the United States is subject to acceptance by the FDA of an IND and finalizing the trial design based on discussions with the FDA. Commencing clinical trials in jurisdictions outside of the United States is similarly subject to acceptance by the applicable regulatory authority of clinical trial documentation following discussions with such authority. In the event that the FDA or other applicable regulatory authority requires Yarrow to complete additional preclinical studies or Yarrow is required to satisfy other FDA or foreign regulatory authority requests, respectively, prior to commencing clinical trials, the start of Yarrow’s first clinical trial for a product candidate may be delayed. Even after Yarrow receives and incorporates guidance from these regulatory authorities, the FDA or other regulatory authorities could disagree as to whether Yarrow has satisfied their requirements to commence any clinical trial or change their position on the acceptability of Yarrow’s trial design or the clinical endpoints selected,

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which may require Yarrow to complete additional preclinical studies or clinical trials, delay the enrollment of Yarrow’s clinical trials or impose stricter approval conditions than Yarrow currently expects. There are analogous processes and risks applicable to clinical trial applications in other countries.

Yarrow may not have the financial resources to continue development of its product candidates if Yarrow experiences any issues that delay or prevent regulatory approval of, or Yarrow’s ability to commercialize, its product candidates. Yarrow or its current or future collaborators’ inability to complete development of, or commercialize Yarrow’s product candidates, or significant delays in doing so, could have a material and adverse effect on Yarrow’s business, financial condition, results of operations and prospects.

Yarrow is substantially dependent on the success of YB-101, and Yarrow’s anticipated future clinical trials of such product candidate may not be successful.

Yarrow’s future success is substantially dependent on its ability to timely obtain regulatory approval for, and then successfully commercialize, YB-101. Yarrow is initially investing a majority of its efforts and financial resources into the research and development of this product candidate. Yarrow expects to initiate a combined Phase 2a/Phase 2b trial of YB-101 in adult patients with GD who are well-controlled on oral anti-thyroid drugs (“ATDs”) with GD in the first half of 2026 and is exploring a clinical development plan for YB-101 in adult patients with TED in the United States and other territories outside of China. The success of YB-101 is dependent on observing YB-101 blocking the pathogenic activity of thyroid-stimulating autoantibodies that drive disease progression in GD and TED with an improved safety and tolerability profile compared to the current standard of care. To the extent Yarrow does not observe this blocking of pathogenic activity of thyroid-stimulating autoantibodies or improved safety, efficacy, pharmacokinetic and pharmacodynamic properties in Yarrow’s Phase 2a/Phase 2b clinical trial of YB-101 or in additional clinical trials, it would significantly and adversely affect the clinical and commercial potential of YB-101.

Yarrow’s product candidates will require additional clinical development, evaluation of clinical, preclinical and manufacturing activities, regulatory approval in multiple jurisdictions, substantial investment and significant marketing efforts before Yarrow generates any revenues from product sales. Yarrow is not permitted to market or promote these product candidates, or any other product candidates, before Yarrow receives regulatory approval from the FDA and comparable foreign regulatory authorities, and Yarrow may never receive such regulatory approvals.

The success of Yarrow’s product candidates will depend on a variety of factors. Yarrow does not have complete control over many of these factors, including certain aspects of clinical development and the regulatory submission process, potential threats to Yarrow’s intellectual property rights, potential threats from the intellectual property rights of third parties and the manufacturing, marketing, distribution and sales efforts of any current or future collaborator. Accordingly, Yarrow cannot assure you that it will ever be able to generate revenue through the sale of these product candidates, even if approved. If Yarrow is not successful in obtaining regulatory approval and commercializing YB-101 or future product candidates, or are significantly delayed in doing so, Yarrow’s business will be materially harmed.

If Yarrow does not achieve its projected development objectives in the time frames Yarrow announces and expects, the commercialization of its product candidates may be delayed, which may harm Yarrow’s reputation and prospects, increase its expenses and cause the Combined Company’s stock price to decline.

From time to time, Yarrow estimates the timing of the anticipated accomplishment of various scientific, clinical, regulatory and other product development goals, which Yarrow sometimes refers to as milestones. These milestones may include the commencement or completion of scientific studies and clinical trials, such as the expected timing for the initiation of Yarrow’s Phase 2a/2b clinical trial of YB-101 in adult patients with GD, the timing for receipt of clinical data from Yarrow’s clinical trials of YB-101 and the timing for the submission of regulatory filings. From time to time, Yarrow may publicly announce the expected timing of some of these milestones. All of these milestones are and will be based on numerous assumptions. The actual timing of these milestones can vary dramatically compared to Yarrow’s estimates, in many cases for reasons beyond Yarrow’s control. If Yarrow does not meet these milestones as publicly announced, or at all, Yarrow’s prospects and reputation may be adversely affected and the Combined Company’s stock price may decline. Additionally, delays relative to Yarrow’s projected timelines are likely to cause overall expenses to increase, which may require Yarrow to raise additional capital sooner than expected and prior to achieving targeted development milestones.

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Yarrow’s projections regarding the market opportunities for its product candidates may not be accurate, and the actual market for Yarrow’s products may be smaller than Yarrow estimates.

The precise incidence and prevalence for all the conditions Yarrow aims to address with its product candidates are unknown. Yarrow’s projections of both the number of people who have these diseases, as well as the subset of people with these diseases who have the potential to benefit from treatment with Yarrow’s product candidates, are based on Yarrow’s beliefs and estimates. These estimates have been derived from a variety of sources, including sales of Yarrow’s competitors, scientific literature, surveys of clinics, patient foundations or market research, and may prove to be incorrect in general, or as to their applicability to Yarrow. Further, new trials may change the estimated incidence or prevalence of these diseases. The total addressable market across all of Yarrow’s product candidates will ultimately depend upon, among other things, the diagnosis criteria included in the final labeling for each of Yarrow’s product candidates approved for sale for these indications, the ability of Yarrow’s product candidates to improve on the safety, convenience, cost and efficacy of competing therapies or therapies in development, acceptance by the medical community and patients, drug pricing and reimbursement.

Yarrow intends to initially seek regulatory approval of YB-101 as treatment for patients with GD and is exploring a clinical development plan for patients with TED. The number of patients in the United States and other major markets may turn out to be lower than expected, patients may not be otherwise amenable to treatment with Yarrow’s product candidates or new patients may become increasingly difficult to identify or gain access to, all of which would adversely affect Yarrow’s business, financial condition, results of operations and prospects. Yarrow may be unable to penetrate the existing GD and TED markets and successfully commercialize its product candidates, if approved. Further, even if Yarrow obtains significant market share for Yarrow’s product candidates, because some of its potential target populations are very small, Yarrow may never achieve profitability despite obtaining such significant market share.

In addition, the market for GD and TED therapies may fail to continue its growth, or may shrink, which could affect the commercial viability of Yarrow’s product candidates and could negatively impact revenues from any approved products. For example, sales of TEPEZZA^® may fall, and this could cause Yarrow’s business to be negatively impacted.

Clinical development involves a lengthy and expensive process that is subject to delays and with uncertain outcomes, and results of earlier studies and trials may not be predictive of future clinical trial results. If Yarrow’s clinical trials and any future preclinical studies are not sufficient to support regulatory approval of any of its product candidates, Yarrow may incur additional costs or experience delays in completing, or ultimately be unable to complete, the development of such product candidate.

Before obtaining regulatory approval from regulatory authorities for the sale of any product candidate, Yarrow must conduct extensive clinical trials to demonstrate the safety and efficacy of Yarrow’s product candidate in humans. Yarrow’s clinical trials may not be conducted as planned or completed on schedule, if at all, and failure can occur at any time during the preclinical study or clinical trial process. A failure of one or more clinical trials can occur at any clinical trial phase. The outcome of preclinical studies and early-stage clinical trials may not be predictive of the success of later clinical trials. Moreover, preclinical and clinical data are often susceptible to varying interpretations and analyses, and many companies that have believed their product candidates performed satisfactorily in preclinical studies and clinical trials have nonetheless failed to obtain regulatory approval of their product candidates.

Yarrow cannot be sure that the FDA or comparable foreign regulatory authorities will agree with Yarrow’s clinical development plans. If the FDA or comparable foreign regulatory authorities require Yarrow to conduct additional trials or enroll additional patients, Yarrow’s development timelines may be delayed. Yarrow cannot be sure that submission of an IND or similar foreign application will result in the FDA or comparable foreign regulatory authorities, as applicable, allowing clinical trials to begin in a timely manner, if at all. Moreover, even if these trials begin, issues may arise that could cause regulatory authorities to suspend or terminate such clinical trials. Events that may prevent successful or timely initiation or completion of clinical trials include: inability to generate sufficient preclinical, toxicology or other in vivo or in vitro data to support the initiation or continuation of clinical trials; delays in reaching a consensus with regulatory authorities on study design or implementation of the clinical trials; delays or failure in obtaining regulatory authorization to commence a trial; delays in reaching agreement on acceptable terms with prospective CROs and clinical trial sites, the terms of which can be subject to extensive negotiation and may vary significantly among different CROs and clinical trial sites; delays in identifying, recruiting and training suitable clinical investigators; delays in obtaining required IRB approval or positive ethics committee opinions at each clinical trial site; delays in manufacturing, testing, releasing, validating or importing/exporting sufficient stable quantities of Yarrow’s product candidates for use in clinical trials or the inability to do any of the foregoing; failure by Yarrow’s CROs, other third parties or Yarrow to adhere to clinical trial protocols; failure to perform in accordance with the FDA’s or any other regulatory authority’s good clinical practice (“GCP”) requirements or regulatory guidelines; changes to the clinical trial protocols; clinical sites deviating from trial protocol or dropping out of a trial; changes in regulatory requirements, guidance or clinical

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trial plans that require amending or submitting new clinical protocols; selection of clinical endpoints that require prolonged periods of observation or analyses of resulting data; transfer of manufacturing processes to new or larger-scale facilities and delays or failure by Yarrow’s CMOs or Yarrow to make any necessary changes to such manufacturing process; and third parties being unwilling or unable to satisfy their contractual obligations to Yarrow.

Yarrow could also encounter delays if a clinical trial is suspended or terminated by Yarrow, by the IRBs or ethics committees of the institutions in which such clinical trials are being conducted, by the Data Safety Monitoring Board, if any, for such clinical trial or by the FDA or comparable foreign regulatory authorities. Such authorities may suspend or terminate a clinical trial due to a number of factors, including failure to conduct the clinical trial in accordance with regulatory requirements or Yarrow’s clinical trial protocols, inspection of the clinical trial operations or trial site by the FDA or comparable foreign regulatory authorities resulting in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, failure to demonstrate a benefit from the product candidate, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial. If Yarrow is required to conduct additional clinical trials or other testing of its product candidates beyond those that Yarrow currently contemplates, if Yarrow is unable to successfully complete clinical trials of its product candidates, if the results of these trials are not positive or are only moderately positive or if there are safety concerns, Yarrow’s business and results of operations would be adversely affected.

Yarrow may find it difficult to enroll and maintain patients in its clinical trials, in part due to the limited number of patients and significant competition for patients who have the diseases for which YB-101 is being developed. If Yarrow encounters difficulties enrolling patients in its expected clinical trial of YB-101 or other future clinical trials, Yarrow’s clinical development activities could be delayed or otherwise adversely affected.

Yarrow may experience difficulties in patient enrollment in its future clinical trials for a variety of reasons. The timely completion of clinical trials in accordance with their protocols depends, among other things, on Yarrow’s ability to enroll a sufficient number of patients who remain in the trial until its conclusion. In particular, because Yarrow is initially focused on developing product candidates for indications for which there is significant competition for recruiting patients, Yarrow may encounter challenges for patient enrollment when Yarrow commences clinical trials for its product candidates. Further, ATDs are the current treatment option for the treatment of GD, TEPEZZA^® is approved for the treatment of TED, and additional products may gain approval in the future, and patients may decide, or physicians may recommend, to use such approved treatments instead of enrolling in clinical trials.

The enrollment of patients in future trials for any of Yarrow’s product candidates will depend on many factors, including:

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Additionally, the number of patients required for clinical trials of Yarrow’s product candidates may be larger than Yarrow anticipates. Even if Yarrow is able to enroll a sufficient number of patients for its future clinical trials, Yarrow may have difficulty maintaining patients in its clinical trials. Yarrow’s inability to enroll or maintain a sufficient number of patients would result in significant delays in completing clinical trials or receipt of regulatory approvals and increased development costs or may require Yarrow to abandon one or more clinical trials altogether, which could cause Yarrow’s value to decline, limit its ability to obtain additional financing and otherwise harm Yarrow’s prospects.

Preliminary, “topline” or interim data from Yarrow’s clinical trials that Yarrow announces or publishes from time to time may change as more patient data become available and are subject to audit and verification procedures.

From time to time, Yarrow may publicly disclose preliminary or topline data from its future preclinical studies and clinical trials, which are based on a preliminary analysis of then-available data. The results and related findings and conclusions are subject to change following a more comprehensive review of the data. Yarrow also makes assumptions, estimations, calculations and conclusions as part of its analyses of these data without the opportunity to fully and carefully evaluate complete data. As a result, the preliminary or topline results that Yarrow reports may differ from future results of the same studies, or different conclusions or considerations may qualify such results, once additional data have been received and fully evaluated or subsequently made subject to audit and verification procedures.

Any preliminary or topline data should be viewed with caution until the final data are available. From time to time, Yarrow may also disclose interim data from its future preclinical studies and clinical trials. Interim data are subject to the risk that one or more of the clinical outcomes may materially change as patient enrollment continues and more patient data become available or as patients from Yarrow’s clinical trials continue other treatments. Further, others, including regulatory authorities, may not accept or agree with Yarrow’s assumptions, estimates, calculations, conclusions or analyses or may interpret or weigh the importance of data differently, which could impact the value of the particular product candidate, the approvability or commercialization of the particular product candidate and of Yarrow as a company. In addition, the information Yarrow chooses to publicly disclose regarding a particular preclinical study or clinical trial is based on what is typically extensive information, and you or others may not agree with what Yarrow determines is material or otherwise appropriate information to include in Yarrow’s disclosure. As a result, you or others may have reached different conclusions based on such extensive information in comparison to Yarrow’s publicly disclosed conclusion regarding a particular preclinical study or clinical trial. If the preliminary, topline or interim data that Yarrow reports differ from actual results, or if others, including regulatory authorities, disagree with the conclusions reached, Yarrow’s ability to obtain approval for, and commercialize, Yarrow’s product candidates may be harmed, which could harm Yarrow’s business, operating results, prospects or financial condition.

Yarrow’s future clinical trials or those of its current or future collaborators may reveal significant adverse events or undesirable side effects not observed in previously conducted preclinical studies or clinical trials and may result in a safety profile that could halt clinical development, inhibit regulatory approval or limit commercial potential or market acceptance of any of Yarrow’s product candidates.

Results of Yarrow’s clinical trials could reveal a high or unacceptable severity and prevalence of side effects, adverse events or unexpected characteristics. Yarrow has not yet completed any clinical trials in humans. If significant adverse events or other side effects are observed in any of Yarrow’s future clinical trials, Yarrow may have difficulty recruiting patients to such trials, patients may drop out of Yarrow’s trials, or Yarrow may be required to abandon the trials or Yarrow’s development efforts of one or more product candidates altogether. For example, although YB-101 is not expected to be associated with the hepatotoxicity or agranulocytosis risks known to occur with ATDs based on GenSci’s preclinical studies, it is possible that patients in Yarrow’s future clinical trials could exhibit the same or similar adverse events. In another example, hearing impairment observed in TEPEZZA^®, or other negative side effects of other products in development for the treatment of TED, may negatively affect clinical trials for Yarrow’s product candidates, delay regulatory approval or result in a restrict drug label, if approved. Yarrow, the FDA or other applicable regulatory authorities, or an IRB or ethics committee, may suspend any clinical trials of any product candidate at any time for various reasons, including a belief that subjects or patients in such trials are being exposed to unacceptable health risks or adverse side effects. Some potential products developed in the biotechnology industry that initially showed therapeutic promise in early-stage studies and trials have later been found to cause side effects that prevented their further development. Other potential products have shown side effects in preclinical studies, which side effects do not present themselves in clinical trials in humans. Even if the side effects do not preclude the product candidate from obtaining or maintaining regulatory approval, undesirable side effects may inhibit market acceptance of the approved product due to Yarrow’s tolerability versus other therapies. Treatment-emergent adverse events could also affect patient recruitment or the ability of enrolled subjects to complete Yarrow’s clinical trials or could result in potential product liability claims. Potential side effects associated with Yarrow’s product candidates may not be appropriately recognized or managed by the treating

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medical staff, as toxicities resulting from Yarrow’s product candidates may not be normally encountered in the general patient population and by medical personnel. Any of these occurrences could harm Yarrow’s business, financial condition, results of operations and prospects significantly.

In addition, even if Yarrow successfully advances its product candidates or any future product candidate through clinical trials, such trials will only include a limited number of patients and limited duration of exposure to Yarrow’s product candidates. As a result, Yarrow cannot be assured that adverse effects of Yarrow’s product candidates will not be uncovered when a significantly larger number of patients are exposed to the product candidate after approval. Further, any clinical trials may not be sufficient to determine the effect and safety consequences of using Yarrow’s product candidates over a multi-year period.

If any of the foregoing events occur or if one or more of Yarrow’s product candidates prove to be unsafe, Yarrow’s entire pipeline could be affected, any of which would have a material adverse effect on Yarrow’s business, financial condition, results of operations and prospects.

Yarrow may expend its limited resources to pursue a particular product candidate and fail to capitalize on product candidates that may be more profitable or for which there is a greater likelihood of success.

Because Yarrow has limited financial and managerial resources, Yarrow is focusing its research and development efforts on its lead product candidate, YB-101. As a result, Yarrow may forgo or delay pursuit of opportunities with other product candidates that later prove to have greater commercial potential. Yarrow’s resource allocation decisions may cause Yarrow to fail to capitalize on viable commercial products or profitable market opportunities. Yarrow’s spending on current and future research and development product candidates for specific indications may not yield any commercially viable product candidates. If Yarrow does not accurately evaluate the commercial potential or target market for a particular product candidate, Yarrow may relinquish valuable rights to that product candidate through collaboration, licensing or other royalty arrangements in cases in which it would have been more advantageous for Yarrow to retain sole development and commercialization rights to such product candidate. In addition, Yarrow may select product candidates amongst a variety of potential product candidates, and the product candidates Yarrow selects may fail to be viable commercial products or the product candidates Yarrow does not select may have a greater likelihood of success.

Even if YB-101 or any future product candidates are approved, such products may not achieve adequate market acceptance among clinicians, patients, healthcare third-party payors and others in the medical community necessary for commercial success and Yarrow may not generate any future revenue from the sale or licensing of such products.

Even if regulatory approval is obtained for YB-101 or one of Yarrow’s future product candidates, Yarrow may not gain market acceptance among physicians, healthcare professionals, patients, healthcare payors or the medical community. Yarrow may not generate or sustain revenue from sales of the product due to factors such as whether the product can be sold at a competitive cost and whether it will otherwise be accepted in the market. Market acceptance will depend on many factors, including factors that are not within Yarrow’s control. There are product candidates in the later stages of development for the treatment of GD, including Vyvgart^®, IMVT-1402 and BHV-1300. TEPEZZA^® was recently approved for TED, and there are multiple product candidates in later stages of development, for the treatment of TED, including Veligrotug, VRDN-003, Batoclimab and pacibekitug. However, YB-101 is designed to block the pathogenic activity of thyroid-stimulating autoantibodies that drive disease progression in GD and TED; to date, no such therapy that inhibits the biological pathway responsible for both hyperthyroidism and orbitopathy while avoiding systemic immunosuppression has been approved by the FDA for the treatment of both GD and TED, though several such agents are in advanced clinical development and close to approval. Market participants with significant influence over acceptance of new treatments, such as clinicians and third-party payors, may not adopt a biologic that incorporates TSHR targeting antibodies for Yarrow’s targeted indication, and Yarrow may not be able to convince the medical community and third-party payors to accept and use, or to provide favorable reimbursement for, any product candidates developed by Yarrow or its existing or future collaborators. Market acceptance of Yarrow’s product candidates may be negatively impacted by potential poor performance of Yarrow’s competitors, including the occurrence of serious adverse events in such competitors’ clinical trials or failure by such competitors to obtain and maintain regulatory approval for their product candidates. Additionally, although Yarrow believes that the improved dosing and convenience Yarrow expects its product candidates to provide will improve market acceptance of such product candidates and that Yarrow’s candidates will have a competitive efficacy profile, Yarrow’s predictions may not be accurate and other competitive products may instead gain and hold the applicable market. Sales of medical products also depend on the willingness of clinicians to prescribe the treatment. Yarrow cannot predict whether clinicians, clinicians’ organizations, hospitals, other healthcare providers, government agencies or private insurers will determine that Yarrow’s product is safe, therapeutically effective, cost effective or less burdensome as compared with competing treatments. If any current or future product candidate is approved but does not achieve an

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adequate level of acceptance by such parties, Yarrow may not generate or derive sufficient revenue from that product candidate and may not become or remain profitable.

Yarrow plans to conduct clinical trials for product candidates at sites outside the United States, and the FDA may not accept data from trials conducted in such locations.

Yarrow plans to conduct its Phase 2a/2b clinical trial of YB-101 for the treatment of GD in the United States and other territories outside of China, and Yarrow may choose to conduct one or more of its future clinical trials outside the United States in whole or in part. Although the FDA may accept data from clinical trials conducted outside the United States, acceptance of this data is subject to conditions imposed by the FDA. For example, the clinical trial must be well designed and conducted and performed by qualified investigators in accordance with ethical principles. The trial population must also adequately represent the U.S. population, and the data must be applicable to the U.S. population and U.S. medical practice in ways that the FDA deems clinically meaningful. In addition, while these clinical trials are subject to the applicable local laws, FDA acceptance of the data will depend on Yarrow’s determination that the trials also complied with all applicable U.S. laws and regulations. Many foreign regulatory authorities have similar requirements for clinical data gathered outside of their respective jurisdictions. In addition, such foreign trials would be subject to the applicable local laws of the foreign jurisdictions where the trials are conducted. There can be no assurance that the FDA or any comparable foreign regulatory authority will accept data from trials conducted outside of the United States or the relevant jurisdiction, as applicable. If the FDA or any comparable foreign regulatory authority does not accept such data, it would likely result in the need for additional trials, which would be costly and time-consuming and would delay or permanently halt Yarrow’s development of the applicable product candidates or delay or prevent regulatory approval for commercialization in the applicable jurisdiction. Even if the FDA or any comparable foreign regulatory authority accepted such data, it could require Yarrow to modify its planned clinical trials to receive clearance to initiate such trials in the United States or the relevant jurisdiction, as applicable, or to continue such trials once initiated.

Further, conducting international clinical trials presents additional risks that may delay completion of Yarrow’s clinical trials. These risks include the failure of enrolled patients in foreign countries to adhere to clinical protocol as a result of differences in healthcare services or cultural customs that could restrict or limit Yarrow’s ability to conduct its clinical trials, the administrative burdens of conducting clinical trials under multiple sets of foreign regulations, foreign exchange fluctuations, diminished protection of intellectual property in some countries, as well as political and economic risks relevant to foreign countries.

Risks Related to Yarrow’s Reliance on Third Parties

Yarrow relies on collaborations and licensing arrangements with third parties, including GenSci. If Yarrow is unable to maintain these collaborations or licensing arrangements, or if these collaborations or licensing arrangements are not successful, Yarrow’s business could be negatively impacted.

Yarrow relies on its collaboration with a third party, GenSci, for the rights necessary to develop and commercialize YB-101 outside of China. In the future, Yarrow could also rely on additional licensing arrangements with third parties. For example, Yarrow has entered into the GenSci License Agreement. However, GenSci could terminate the GenSci License Agreement under certain circumstances, including Yarrow’s failure to make any payments owed to GenSci under the agreement or any uncured material breach of the agreement by Yarrow, in which event Yarrow may lose intellectual property rights and may not be able to develop or commercialize the YB-101.

Collaborations or licensing arrangements that Yarrow enters into may not be successful, and any success will depend heavily on the efforts and activities of such collaborators or licensors. If any of Yarrow’s collaborators or licensors experiences delays in performance of, or fails to perform, their obligations under their agreement with Yarrow, disagrees with Yarrow’s interpretation of the terms of such agreement or terminates their agreement with Yarrow, Yarrow’s pipeline and product candidates and development timeline could be adversely affected. If Yarrow fails to comply with any of the obligations under its collaborations or license agreements, including payment terms and diligence terms, Yarrow’s collaborators or licensors may have the right to terminate such agreements, in which event Yarrow may lose intellectual property rights and may not be able to develop, manufacture, market or sell the products covered by Yarrow’s agreements or may face other penalties under Yarrow’s agreements. Yarrow’s collaborators and licensors may also fail to properly maintain or defend the intellectual property Yarrow has licensed from them, if required by Yarrow’s agreement with them, leading to the potential invalidation of Yarrow’s intellectual property, or they may even infringe upon Yarrow’s intellectual property rights, any of which could subject Yarrow to litigation or arbitration, which would be time-consuming and expensive and could harm Yarrow’s ability to commercialize its product candidates. In addition, collaborators could independently develop, or develop with third parties, products that compete directly or indirectly with Yarrow’s product candidates

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and products if the collaborators believe that the competitive products are more likely to be successfully developed or can be commercialized under terms that are more economically attractive than Yarrow’s.

As part of Yarrow’s strategy, Yarrow plans to evaluate additional opportunities to enhance its capabilities and expand its development pipeline or add development or commercialization capabilities. Yarrow may not realize the benefits of such collaborations, alliances or licensing arrangements. Any of these relationships may require Yarrow to incur non-recurring and other charges, increase Yarrow’s near and long-term expenditures, issue securities that dilute the Combined Company’s existing stockholders or disrupt Yarrow’s management and business.

Yarrow may face significant competition in attracting appropriate collaborators, and more established companies may also be pursuing strategies to license or acquire third-party intellectual property rights that Yarrow considers attractive. These companies may have a competitive advantage over Yarrow due to their size, financial resources and greater clinical development and commercialization capabilities. In addition, companies may be unwilling to assign or license rights to Yarrow, whether they perceive Yarrow to be a competitor or for other reasons. Whether Yarrow reaches a definitive agreement for a collaboration will depend, among other things, upon Yarrow’s assessment of the collaborator’s resources and expertise, the terms and conditions of the proposed collaboration and the proposed collaborator’s evaluation of a number of factors. Collaborations are complex and time-consuming to negotiate, document and execute. In addition, consolidation among large pharmaceutical and biotechnology companies has reduced the number of potential future collaborators. Yarrow may not be able to negotiate additional collaborations on a timely basis, on acceptable terms or at all. If Yarrow fails to enter into collaborations and does not have sufficient funds or expertise to undertake the necessary development and commercialization activities, Yarrow may not be able to further develop its product candidates or bring them to market.

Risks associated with the in-licensing or acquisition of product candidates could cause substantial delays in the preclinical and clinical development of Yarrow’s product candidates.

Yarrow has relied and continues to rely on GenSci, and expects to rely on Yarrow’s future licensing partners, to (i) conduct research and development in accordance with the applicable protocol, legal, regulatory and scientific standards, (ii) accurately report the results of all preclinical and clinical trials conducted prior to Yarrow’s licensing or acquisition of the relevant product candidates and (iii) correctly collect and interpret the data from these trials. If the research and development processes or the results of the product candidates development prior to Yarrow’s licensing or acquisition of Yarrow’s product candidates prove to be unreliable, this could result in increased costs and delays in the development of Yarrow’s product candidates, which could adversely affect any future revenue from such product candidates, if approved.

Yarrow may also acquire or in-license additional product candidates for preclinical or clinical development in the future as Yarrow continues to build its pipeline. The risks associated with acquiring or in-licensing product candidates could result in delays in the commencement or completion of Yarrow’s preclinical studies and clinical trials, if they are ever commenced or completed, and Yarrow’s ability to generate revenues from its product candidates may be delayed. Please see the section titled “Risk Factors — Risks Related to Yarrow’s Intellectual Property — If Yarrow is unable to obtain or maintain necessary rights to YB-101 or its future product candidates through acquisitions and in-licenses, Yarrow’s business may be materially harmed” below for additional information regarding such risks.

Yarrow currently relies, and plans to rely in the future, on third parties to conduct and support its future preclinical studies and clinical trials. If these third parties do not properly and successfully carry out their contractual duties or meet expected deadlines, Yarrow may not be able to obtain regulatory approval of or commercialize Yarrow’s product candidates.

Yarrow plans to utilize and depend upon independent investigators and collaborators, such as medical institutions, CROs, contract testing labs and strategic partners, to conduct and support Yarow’s anticipated clinical trials and future preclinical studies. Yarrow will rely heavily on these third parties over the course of its preclinical studies and clinical trials, and Yarrow controls only certain aspects of their activities. As a result, Yarrow will have less direct control over the conduct, timing and completion of these preclinical studies and clinical trials and the management of data developed through preclinical studies and clinical trials than would be the case if Yarrow was relying entirely upon its own staff. Nevertheless, Yarrow is responsible for ensuring that each of its studies and trials is conducted in accordance with the applicable protocol, legal, regulatory and scientific standards, and Yarrow’s reliance on these third parties does not relieve Yarrow of its regulatory responsibilities. Yarrow and its third-party contractors and CROs are required to comply with GCP, which are regulations and guidelines enforced by the FDA and comparable foreign regulatory authorities for all of Yarrow’s product candidates in clinical development. If Yarrow or any of these third parties fail to comply with applicable GCP regulations, the clinical data generated in Yarrow’s clinical trials may be deemed unreliable and the FDA or comparable foreign

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regulatory authorities may require Yarrow to perform additional clinical trials before approving Yarrow’s marketing applications. Yarrow cannot assure you that, upon inspection by a given regulatory authority, such regulatory authority will determine that any of Yarrow’s clinical trials comply with GCP. In addition, Yarrow’s clinical trials must be conducted with products manufactured in accordance with cGMP. Yarrow’s failure to comply with these requirements may require Yarrow to repeat clinical trials, which would delay the regulatory approval process. Moreover, Yarrow’s business may be implicated if any of these third parties violates federal or state fraud and abuse or false claims laws and regulations or healthcare privacy and security laws, and foreign equivalents.

Any third parties conducting Yarrow’s clinical trials will not be its employees and, except for remedies available to Yarrow under its agreements with such third parties, Yarrow cannot control whether they devote sufficient time and resources to Yarrow’s product candidates. These third parties may encounter challenges hiring and retaining sufficient qualified personnel or they may be involved in mergers, acquisitions or similar transactions and may have relationships with other commercial entities, including Yarrow’s competitors, for whom they may also be conducting clinical trials or other product development activities, which could negatively affect their performance on Yarrow’s behalf and the timing thereof and could lead to products that compete directly or indirectly with Yarrow’s current or future product candidates. If these third parties do not successfully carry out their contractual duties or obligations or meet expected deadlines, if they need to be replaced or if the quality or accuracy of the clinical data they obtain is compromised due to the failure to adhere to Yarrow’s clinical protocols or regulatory requirements or for other reasons, Yarrow’s clinical trials may be extended, delayed or terminated and Yarrow may not be able to complete development of, obtain regulatory approval of or successfully commercialize its product candidates. In addition, Yarrow relies on GenSci and expects to continue to rely on foreign CROs and CMOs for formulation and manufacturing of Yarrow’s Phase 2a/2b clinical trial materials, and will likely continue to rely on foreign CROs and CMOs in the future.

The biopharmaceutical industry in China is strictly regulated by the Chinese government. Changes to Chinese regulations or government policies affecting biopharmaceutical companies are unpredictable and may have a material adverse effect on Yarrow’s collaborators in China which could have an adverse effect on Yarrow’s business, financial condition, results of operations and prospects. In addition, the United States government has imposed significant tariffs on imports from China and other countries and may impose more restrictions on goods, including biologically derived substances, manufactured in or imported from China or other countries or impose other restrictions on companies’ ability to work with Chinese or other foreign counterparties. Evolving changes in China’s public health, economic, political, and social conditions and uncertainty around China’s relationship with other governments, such as the United States and the UK, could also negatively impact Yarrow’s ability to manufacture its product candidates for its planned clinical trials or have an adverse effect on its ability to secure government funding, which could adversely affect Yarrow’s financial condition and cause Yarrow to delay its clinical development of YB-101 or its future product candidates. Furthermore, if one or more of Yarrow’s collaborators or vendors in China is named a biotechnology company of concern under the BIOSECURE Act, which was enacted into law on December 18, 2025, Yarrow’s operations and financial condition may be negatively impacted as a result of any delays or increased costs arising from the trade restrictions and other foreign regulatory requirements affecting such collaborators. In addition, while Yarrow has established relationships with CROs and CMOs outside of China, moving to those suppliers in the event of a geopolitical instability affecting Yarrow’s collaborators in China could introduce delays into the development of YB-101 or its future product candidates.

Yarrow relies on the use of third-party CMOs to manufacture Yarrow’s product candidates, and Yarrow expects to continue to rely on third-party CMOs to produce Yarrow’s products, if approved. Yarrow’s business could be adversely affected if Yarrow is unable to use third-party manufacturing sites or if the third-party manufacturers encounter difficulties in production.

Yarrow does not currently own any facility that may be used as Yarrow’s clinical-scale manufacturing and processing facility and must rely on CMOs to manufacture Yarrow’s product candidates. Yarrow has not yet caused its product candidates to be manufactured on a commercial scale and may not be able to do so for any of Yarrow’s product candidates, if approved. Yarrow currently solely relies on GenSci to provide biological development and manufacturing services. If there should be any disruption in such supply arrangement, including any adverse events affecting Yarrow’s sole supplier, or if Yarrow experiences delays or difficulties in transferring, or is unable to successfully transfer, Yarrow’s manufacturing processes, it could have a negative effect on the clinical development of Yarrow’s product candidates and other operations while Yarrow works to identify and qualify an alternate supply source. Yarrow has limited control over the manufacturing process of, and may be dependent on, Yarrow’s contract manufacturing partners for compliance with cGMP requirements and any other regulatory requirements of the FDA or comparable foreign regulatory authorities for the manufacture of Yarrow’s product candidates. Beyond periodic audits, Yarrow has limited control over the ability of its CMOs to maintain adequate quality control, quality assurance and qualified personnel. If the FDA or another applicable regulatory authority does not approve these facilities for the manufacture of Yarrow’s product candidates or withdraws any approval in the future, Yarrow may need to find alternative manufacturing facilities, which would require the incurrence of significant additional costs and delays and materially adversely affect Yarrow’s ability to develop, obtain regulatory approval for or market its

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product candidates, if approved. Yarrow, or its future contract manufacturers, any current or future collaborators and their contract manufacturers could be subject to periodic unannounced inspections by the FDA, competent authorities of member states of the European Union (“EU Member States”) or other comparable foreign regulatory authorities, to monitor and ensure compliance with cGMP. Despite Yarrow’s efforts to audit and verify regulatory compliance, one or more of Yarrow’s third-party manufacturing vendors may be found on regulatory inspection by the FDA, competent authorities of EU Member States or other comparable foreign regulatory authorities to be noncompliant with cGMP regulations. Yarrow’s failure, or the failure of Yarrow’s CMOs, to comply with applicable regulations could result in sanctions being imposed on Yarrow, including fines, injunctions, civil penalties, delays, suspension, variation or withdrawal of approvals, license revocation, seizures or recalls of product candidates or drugs, operating restrictions and criminal prosecutions, any of which could significantly and adversely affect supplies of Yarrow’s product candidates or products, if approved, and harm Yarrow’s business and results of operations.

Moreover, Yarrow’s CMOs may experience manufacturing difficulties due to resource constraints, supply chain issues, intellectual property disputes or as a result of labor disputes or unstable political environments. If any CMOs on which Yarrow will rely fail to manufacture quantities of Yarrow’s product candidates at quality levels necessary to meet regulatory requirements and at a scale sufficient to meet anticipated demand at a commercially reasonable cost, Yarrow’s business, financial condition and prospects could be materially and adversely affected. In addition, Yarrow’s CMOs are responsible for transporting temperature-controlled materials that can be inadvertently degraded during transport due to several factors, rendering certain batches unsuitable for trial use for failure to meet, among others, Yarrow’s integrity and purity specifications. Yarrow and any of its CMOs may also face product seizure or detention or refusal to permit the import or export of products. Yarrow’s business could be materially adversely affected by business disruptions to Yarrow’s third-party providers that could materially adversely affect Yarrow’s anticipated timelines, potential future revenue and financial condition and increase Yarrow’s costs and expenses. Each of these risks could delay or prevent the completion of Yarrow’s anticipated clinical trials and future preclinical studies or the approval of any of Yarrow’s product candidates by the FDA or comparable foreign regulatory authorities, result in higher costs or adversely impact commercialization of Yarrow’s product candidates.

Risks Related to Yarrow’s Business and Operations

In order to successfully implement its plans and strategies, Yarrow will need to grow the size of its organization and Yarrow may experience difficulties in managing this growth.

Yarrow expects to experience significant growth in the number of its employees and the scope of Yarrow’s operations, particularly in the areas of clinical drug development, technical operations, clinical operations and regulatory affairs. To manage its anticipated future growth, Yarrow must continue to implement and improve its managerial, operational and financial personnel and systems, expand Yarrow’s facilities and continue to recruit and train additional qualified personnel. Due to its limited financial resources and the limited experience of its management team working together in managing a company with such anticipated growth, Yarrow may not be able to effectively manage the expansion of its operations or recruit and train additional qualified personnel.

Yarrow is highly dependent on its key personnel and anticipates hiring new key personnel. If Yarrow is not successful in attracting and retaining highly qualified personnel, Yarrow may not be able to successfully implement its business strategy.

Yarrow’s ability to compete in the highly competitive biotechnology and pharmaceutical industries depends upon its ability to attract and retain highly qualified managerial, scientific and medical personnel. Yarrow is highly dependent on Yarrow’s managerial, scientific and medical personnel, including Yarrow’s Chief Executive Officer and other key members of Yarrow’s leadership team. Although Yarrow has entered into employment agreements with Yarrow’s executive officers, each of them may terminate their employment with Yarrow at any time. Yarrow does not maintain “key person” insurance for any of Yarrow’s executives or other employees. The loss of the services of Yarrow’s executive officers or other key employees could impede the achievement of Yarrow’s research, development and commercialization objectives and seriously harm its ability to successfully implement its business strategy. Furthermore, replacing executive officers and key personnel may be difficult and may take an extended period of time. If Yarrow does not succeed in attracting and retaining qualified personnel, it could materially adversely affect Yarrow’s business, financial condition and results of operations. Yarrow could in the future have difficulty attracting and retaining experienced personnel and may be required to expend significant financial resources in Yarrow’s employee recruitment and retention efforts.

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Yarrow’s future growth may depend, in part, on its ability to operate in foreign markets, where Yarrow would be subject to additional regulatory burdens and other risks and uncertainties.

Yarrow’s future growth may depend, in part, on its ability to develop and commercialize its product candidates, if approved, in foreign markets for which Yarrow may rely on collaboration with third parties. Recent and ongoing changes in the United States trade policy with foreign countries, including the continued uncertainty surrounding U.S. tariffs and potential retaliatory measures by foreign governments, may disrupt the global supply chain for biopharmaceutical products. For example, in September 2025, President Trump announced plans to impose 100% tariffs on imported branded or patented pharmaceuticals, unless the importing company is building U.S. manufacturing capacity, although the effective date of such tariffs has been delayed. Certain major drug producers and manufacturers are in negotiations with the U.S. Presidential Administration to receive relief from such tariffs. As a result of these negotiations, certain manufacturers, such as Pfizer, have announced their participation in a new direct purchasing platform called “TrumpRx.gov,” which allows U.S. patients to purchase certain medicines at significant discounts to current retail prices. The discounts may adversely affect revenue generated from participating drugs. The potential impact of this platform on Yarrow’s business is unclear at this time. It is not yet clear whether these tariffs would apply to the importation of active pharmaceutical ingredients and possibly bulk drug products that are intended for use in clinical trials and not for commercial sale, which could increase the costs of materials for Yarrow’s clinical trials. Any direct tariffs, if imposed on pharmaceutical products, may result in increased costs for raw materials and contract manufacturing services, reduced ability to source critical CMOs, and a delay in Yarrow’s development timelines.

Yarrow is not permitted to market or promote any of its product candidates before Yarrow receives regulatory approval from the applicable foreign regulatory authority, and Yarrow may never receive such regulatory approval for any of its product candidates. To obtain separate regulatory approval in many other countries, Yarrow must comply with numerous and varying regulatory requirements of such countries regarding safety and efficacy and governing, among other things, clinical trials and commercial sales, pricing and distribution of Yarrow’s product candidates, if approved, and Yarrow cannot predict success in these jurisdictions. If Yarrow fails to comply with the regulatory requirements in international markets and receive applicable regulatory approvals, Yarrow’s target market will be reduced and Yarrow’s ability to realize the full market potential of its product candidates will be harmed and its business will be adversely affected. Moreover, even if Yarrow obtains approval of its product candidates and ultimately commercialize its product candidates in foreign markets, Yarrow would be subject to the risks and uncertainties, including the burden of complying with complex and changing foreign regulatory, tax, accounting and legal requirements and reduced protection of intellectual property rights in some foreign countries.

Yarrow’s employees, independent contractors, consultants, commercial collaborators, principal investigators, CROs, CMOs, suppliers and vendors may engage in misconduct or other improper activities, including noncompliance with regulatory standards and requirements.

Yarrow is exposed to the risk that its employees, independent contractors, consultants, commercial collaborators, principal investigators, CROs, CMOs, suppliers and vendors acting for or on its behalf may engage in misconduct or other improper activities. Misconduct by these parties could include intentional, reckless or negligent conduct or disclosure of unauthorized activities to Yarrow that violates FDA regulations, including those laws requiring the reporting of true, complete and accurate information to the FDA, manufacturing standards, federal and state healthcare laws and regulations, and laws that require the true, complete and accurate reporting of financial information or data. In particular, sales, marketing and business arrangements in the healthcare industry are subject to extensive laws and regulations intended to prevent fraud, kickbacks, self-dealing and other abusive practices. These laws and regulations may restrict or prohibit a wide range of pricing, discounting, marketing and promotion, sales commission, customer incentive programs and other business arrangements. Misconduct by these parties could also involve the improper use of individually identifiable information, including, without limitation, information obtained in the course of clinical trials, which could result in regulatory sanctions and serious harm to Yarrow’s reputation. Yarrow has adopted a code of conduct, but it is not always possible to identify and deter misconduct by these parties and the precautions Yarrow takes to detect and prevent this activity may not be effective in controlling unknown or unmanaged risks or losses or in protecting Yarrow from governmental investigations or other actions or lawsuits stemming from a failure to comply with these laws or regulations.

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Yarrow’s internal information technology systems, or those of any of its CROs, manufacturers, other contractors or consultants, third party service providers, or existing or future collaborators, may fail or suffer security or data privacy breaches or other unauthorized or improper access to, use of, or destruction of Yarrow’s proprietary or confidential data, employee data or personal data, which could result in additional costs, loss of revenue, significant liabilities, harm to Yarrow’s brand and material disruption of Yarrow’s operations.

In the ordinary course of its business, Yarrow and the third parties upon which Yarrow relies collect, receive, store, process, generate, use, transfer, disclose, make accessible, protect, secure, dispose of, transmit, and share (collectively, “Process”) proprietary, confidential, and sensitive data, including personal data, intellectual property, trade secrets, and other sensitive data (collectively, “Sensitive Information”).

Despite the implementation of security measures in an effort to protect systems that store Yarrow’s information, given their size and complexity and the increasing amounts of information maintained on Yarrow’s internal information technology systems and those of Yarrow’s third-party CROs, other contractors (including sites performing Yarrow’s clinical trials), third party service providers and supply chain companies, and consultants, these systems are potentially vulnerable to breakdown or other damage or interruption from service interruptions, system malfunction, natural disasters, terrorism, war and telecommunication and electrical failures, as well as security breaches from inadvertent or intentional actions by Yarrow’s employees, contractors, consultants, business partners and/or other third parties, or from cyber-attacks by malicious third parties, which may compromise Yarrow’s system infrastructure or lead to the loss, destruction, alteration or dissemination of, or damage to, Yarrow’s data.

Some actors now engage and are expected to continue to engage in cyber-attacks, including without limitation nation-state actors for geopolitical reasons and in conjunction with military conflicts and defense activities. During times of war and other major conflicts, Yarrow, and the third parties upon which Yarrow relies, may be vulnerable to a heightened risk of these attacks, including retaliatory cyber-attacks, that could materially disrupt Yarrow’s systems and operations. In particular, severe ransomware attacks are becoming increasingly prevalent and can lead to significant interruptions in Yarrow’s operations, loss of sensitive data and income, reputational harm, and diversion of funds. Extortion payments may alleviate the negative impact of a ransomware attack, but Yarrow may be unwilling or unable to make such payments due to, for example, applicable laws or regulations prohibiting such payments.

To the extent that any disruption or security breach were to result in loss, destruction, unavailability, alteration or dissemination of, or damage to, Yarrow’s data or applications, or for it to be believed or reported that any of these occurred, Yarrow could incur liability and reputational damage and the development and commercialization of its product candidates could be delayed. Further, Yarrow’s insurance policies may not be adequate to compensate Yarrow for the potential losses arising from any such disruption in, or failure or security breach of, Yarrow’s systems or third-party systems where information important to Yarrow’s business operations or commercial development is stored.

Yarrow’s hybrid workforce may create additional risks for its information technology systems and data because some employees of Yarrow work remotely and utilize network connections, computers, and devices working at home, while in transit and in public locations. In addition, Yarrow’s current office in New Haven may create risks for Yarrow’s information technology systems and data because it is a shared space for which Yarrow does not have its own dedicated network. Additionally, business transactions (such as acquisitions or integrations) could expose Yarrow to additional cybersecurity risks and vulnerabilities, as Yarrow’s systems could be negatively affected by vulnerabilities present in acquired or integrated entities’ systems and technologies.

While Yarrow has implemented security measures designed to protect against security incidents, there can be no assurance that these measures will be effective. Yarrow may be unable in the future to detect vulnerabilities in its information technology systems because such threats and techniques change frequently, are often sophisticated in nature, and may not be detected until after a security incident has occurred. Further, Yarrow may experience delays in developing and deploying remedial measures designed to address any such identified vulnerabilities. Applicable data privacy and security obligations may require Yarrow to notify relevant stakeholders of security incidents. Such disclosures are costly, and the disclosure or the failure to comply with such requirements could lead to adverse consequences.

Yarrow relies on third-party service providers and technologies to operate critical business systems to Process Sensitive Information in a variety of contexts. Yarrow’s ability to monitor these third parties’ information security practices is limited, and these third parties may not have adequate information security measures in place. If its third-party service providers experience a security incident or other interruption, Yarrow could experience adverse consequences. While Yarrow may be entitled to damages if its third-party service providers fail to satisfy their privacy or security-related obligations to Yarrow, any award may be insufficient to cover its damages, or Yarrow may be unable to recover such award. In addition, supply- chain attacks have increased in frequency and severity,

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and Yarrow cannot guarantee that third parties’ infrastructure in Yarrow’s supply chain or Yarrow’s third-party partners’ supply chains have not been compromised.

If Yarrow (or a third party upon whom Yarrow relies) experiences a security incident or is perceived to have experienced a security incident, Yarrow may experience adverse consequences, such as government enforcement actions (for example, investigations, fines, penalties, audits, and inspections); additional reporting requirements and/or oversight; restrictions on Processing Sensitive Information (including personal data); litigation (including class claims); indemnification obligations; negative publicity; reputational harm; monetary fund diversions; interruptions in Yarrow’s operations (including availability of data); financial loss; and other similar harms. Security incidents and attendant consequences may cause stakeholders (including investors and potential customers) to stop supporting Yarrow’s platform, deter new customers from products, and negatively impact Yarrow’s ability to grow and operate Yarrow’s business.

Yarrow’s contracts may not contain limitations of liability, and even where they do, there can be no assurance that limitations of liability in Yarrow’s contracts are sufficient to protect Yarrow from liabilities, damages, or claims related to its data privacy and security obligations. Yarrow cannot be sure that its insurance coverage will be adequate or sufficient to protect Yarrow from or to mitigate liabilities arising out of Yarrow’s privacy and security practices, that such coverage will continue to be available on commercially reasonable terms or at all, or that such coverage will pay future claims.

Yarrow is subject to stringent and changing laws, regulations and standards, and contractual obligations relating to privacy, data protection, and data security. The actual or perceived failure to comply with such obligations could lead to government enforcement actions (which could include civil or criminal penalties), fines and sanctions, private litigation and/or adverse publicity and could negatively affect Yarrow’s operating results and business.

Yarrow, and third parties Yarrow works with, are or may become subject to numerous domestic and foreign laws, regulations, and standards relating to privacy, data protection, and data security, the scope of which is changing, subject to differing applications and interpretations, and may be inconsistent among countries, or conflict with other rules. In addition, Yarrow is and may become subject to the terms of contractual obligations related to privacy, data protection, and data security. Yarrow’s obligations may also change or expand as its business grows. The actual or perceived failure by Yarrow or third parties related to Yarrow to comply with such laws, regulations and obligations could increase Yarrow’s compliance and operational costs, expose Yarrow to regulatory scrutiny, actions, fines and penalties, result in reputational harm, lead to a loss of customers, result in litigation and liability, and otherwise cause a material adverse effect on Yarrow’s business, financial condition, and results of operations.

If Yarrow fails to comply with environmental, health and safety laws and regulations, Yarrow could become subject to fines or penalties or incur costs that could have a material adverse effect on the success of Yarrow’s business.

Yarrow is subject to numerous environmental, health and safety laws and regulations, including those governing laboratory procedures and the handling, use, storage, treatment and disposal of hazardous materials and wastes. Yarrow’s operations may involve the use of hazardous and flammable materials, including chemicals and biological and radioactive materials. In addition, Yarrow may incur substantial costs in order to comply with current or future environmental, health and safety laws and regulations. These current or future laws and regulations may impair Yarrow’s research, development or commercialization efforts. Failure to comply with these laws and regulations also may result in substantial fines, penalties or other sanctions.

Yarrow may be subject to adverse legislative or regulatory tax changes that could negatively impact its financial condition.

The rules governing U.S. federal, state and local income taxation are constantly under review by persons involved in the legislative process and by the Internal Revenue Service (“IRS”) and the U.S. Treasury Department. Changes to tax laws (which changes may have retroactive application) could adversely affect the Combined Company’s stockholders or Yarrow. Yarrow assesses the impact of various tax reform proposals and modifications to existing tax treaties in all jurisdictions where Yarrow has operations to determine the potential effect on its business and any assumptions Yarrow has made about its future taxable income. Yarrow cannot predict whether any specific proposals will be enacted, the terms of any such proposals or what effect, if any, such proposals would have on Yarrow’s business if they were to be enacted.

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For example, the United States enacted the Inflation Reduction Act of 2022, which implements, among other changes, a 1% excise tax on certain stock buybacks. In addition, beginning in 2022, the Tax Cuts and JOBS Act (the “JOBS Act”) eliminated the previously available option to deduct research and development expenditures and requires taxpayers to amortize them generally over five years for research activities conducted in the United States and over fifteen years for research activities conducted outside the United States. July 4, 2025, the U.S. Congress enacted the One Big Beautiful Bill Act, which includes a provision restoring the immediate deductibility of domestic research and development expenditures. The impact of this newly enacted law on Yarrow’s tax position will depend on how the provision is implemented and interpreted by the IRS and other regulatory authorities. In addition, Yarrow has no assurance as to whether, when and how this provision may be subject to further amendment or repeal. Such changes, among others, may adversely affect Yarrow’s effective tax rate, results of operation and financial condition.

Yarrow may acquire businesses, product candidates or products, or form strategic alliances, in the future, and may not realize the benefits of such acquisitions.

Yarrow may acquire additional businesses or products, form strategic alliances, or create joint ventures with third parties that Yarrow believes will complement or augment its existing business. If Yarrow acquires businesses with promising markets or technologies, Yarrow may not be able to realize the benefit of acquiring such businesses if Yarrow is unable to successfully integrate them with its existing operations and company culture. Yarrow may encounter numerous difficulties in developing, manufacturing and marketing any new product candidates or products resulting from a strategic alliance or acquisition that delay or prevent Yarrow from realizing their expected benefits or enhancing Yarrow’s business. There is no assurance that, following any such acquisition, Yarrow will achieve the synergies expected in order to justify the transaction, which could result in a material adverse effect on Yarrow’s business and prospects.

Yarrow maintains its cash at financial institutions, often in balances that exceed federally-insured limits. The failure of financial institutions could adversely affect Yarrow’s ability to pay its operational expenses or make other payments.

Yarrow’s cash held in non-interest-bearing and interest-bearing accounts exceeds the FDIC insurance limits. If such banking institutions were to fail, Yarrow could lose all or a portion of those amounts held in excess of such insurance limitations. For example, the FDIC took control of Silicon Valley Bank in March 2023. The Federal Reserve subsequently announced that account holders would be made whole. However, the FDIC may not make all account holders whole in the event of future bank failures. In addition, even if account holders are ultimately made whole with respect to a future bank failure, account holders’ access to their accounts and assets held in their accounts may be substantially delayed. Any material loss that Yarrow may experience in the future or inability for a material time period to access Yarrow’s cash and cash equivalents could have an adverse effect on Yarrow’s ability to pay its operational expenses or make other payments, which could adversely affect Yarrow’s business.

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Risks Related to Yarrow’s Intellectual Property

Yarrow’s intellectual property portfolio is at an early stage. Yarrow does not currently own any issued patents or pending non-provisional patent applications and Yarrow in-licenses intellectual property rights to YB-101 from GenSci. Therefore, Yarrow’s ability to obtain and protect its patent rights, and protect other proprietary rights, is uncertain, exposing Yarrow to the possible loss of competitive advantage.

Yarrow will rely upon a combination of patents, trademarks, trade secret protection, copyrights and confidentiality agreements and the GenSci License Agreement to protect the intellectual property related to YB-101 and technologies and to prevent third parties from competing unfairly with Yarrow. Yarrow’s success depends in large part on its ability to obtain and maintain patent protection for Yarrow’s product candidates and their uses, as well as Yarrow’s ability to operate without infringing on or violating the proprietary rights of others. If Yarrow is unable to obtain patent protection with respect to YB-101, or any future product candidates, Yarrow’s business, financial condition, results or operations and prospects could be materially harmed.

Yarrow does not currently own or in-license any issued patents, but has filed one U.S. provisional patent application related to methods of treating GD with YB-101. Yarrow intends to file one or more non-provisional patent applications claiming priority to this provisional patent application. However, Yarrow cannot provide assurances that such non-provisional patent application(s) will be filed, nor whether such non-provisional patent application(s), if filed, will issue, the breadth of any resulting issued patent(s), or whether any issued patent(s) will be found to be invalid, unenforceable, or will be challenged by third parties.

Yarrow licenses patent rights to three patent families from GenSci under the GenSci License Agreement. The three patent families include only pending patent applications, and no issued patents. The licensed patent families are directed to monoclonal antibodies targeting the TSHR, including YB-101; methods of treatment with YB-101; and formulations of YB-101. The licensed monoclonal antibodies patent applications are pending, national stage patent applications undergoing patent prosecution. Yarrow cannot provide assurances that these pending national stage patent applications will issue, the breadth of any resulting issued patents, or whether any issued patents will be found to be invalid, unenforceable, or will be challenged by third parties. Both the licensed method of treatment and formulations patent families are pending PCT applications. Yarrow intends to file one or more national stage patent applications from each PCT application. However, Yarrow cannot provide assurances that such national stage patent application(s) will be filed, nor whether such patent application(s), if filed, will issue, the breadth of any resulting issued patent(s), or whether any issued patent(s) will be found to be invalid, unenforceable, or will be challenged by third parties.

Yarrow’s current patent portfolio is limited to owned or licensed pending patent applications. Yarrow’s owned or currently licensed, or future optioned, in-licensed or owned patent applications may not result in patents being issued. Any issued patents may not afford sufficient protection of Yarrow’s product candidates or their intended uses against competitors, nor can there be any assurance that the patents issued will not be infringed, designed around, or invalidated by third parties, or effectively prevent others from commercializing competitive technologies, products or product candidates. Even if these patents are granted, they may be difficult to enforce. Further, any issued patents that Yarrow may license or own covering Yarrow’s product candidates could be narrowed or found invalid or unenforceable if challenged in court or before administrative bodies in the United States or abroad, including the USPTO. If Yarrow does not obtain patent coverage for the work Yarrow is conducting, or if Yarrow obtains such rights but they are invalidated or rendered unenforceable, Yarrow may be unable to exclude competitors from pursuing and marketing the same or similar product candidates. Other risks Yarrow faces if it is not able to obtain and maintain patent coverage for Yarrow’s product candidates are the reduction in valuation of its product candidates, and ultimately of Yarrow as a company, by potential investors, and Yarrow’s inability to assert claims for infringement against third parties or counterclaim against such third parties or negotiate more advantageous settlement parameters. Further, if Yarrow encounters delays in its clinical trials or delays in obtaining regulatory approval, the period of time during which Yarrow could market its product candidates under patent protection would be reduced. Thus, the patents that Yarrow may own or license may not afford Yarrow any meaningful exclusivity period or competitive advantage.

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Yarrow may not be able to obtain or protect Yarrow’s intellectual property rights throughout the world and the legal systems in certain countries may not favor enforcement or protection of at least certain patents, trade secrets or other intellectual property. Filing, prosecuting, maintaining and defending patents on product candidates and other related inventions worldwide would be expensive and Yarrow’s intellectual property rights in some foreign jurisdictions can be less extensive than those in the United States; the reverse may also occur. For example, Yarrow in-licenses from GenSci patent applications in the following foreign jurisdictions: Australia, United Arab Emirates, Canada, European Patent Organization, Japan, Korea, Russia, Qatar, and Saudi Arabia. Government actions in certain jurisdictions, including those in which Yarrow has licensed patent rights, may allow exploitation of intellectual property without the patent owner’s consent. For example, government decrees may allow third parties to exploit patented inventions without authorization, effectively eliminating patent protection in those territories. These actions could result in abandonment or lapse of future patents in the affected jurisdictions. Geopolitical actions in the United States and in foreign countries could increase the uncertainties and costs surrounding the prosecution or maintenance of future patent applications and the maintenance, enforcement, or defense of any future issued patents. As such, Yarrow may not have patents in all countries or all major markets and may not be able to obtain patents in all jurisdictions even if Yarrow or its licensor files patent applications to obtain such rights. Yarrow’s competitors may operate in countries where Yarrow does not have patent protection and may be able to freely use its technologies and discoveries in such countries, at least to the extent not forbidden by law.

In addition to seeking patents for some of its technology and product candidates, Yarrow may also rely on trade secrets, including unpatented know-how, technology and other proprietary information, to maintain Yarrow’s competitive position. Any disclosure, either intentional or unintentional, by Yarrow’s employees, the employees of third parties with whom Yarrow shares its facilities or third-party consultants and vendors that Yarrow engages to perform research, clinical trials or manufacturing activities, or misappropriation by third parties (such as through a cybersecurity breach) of Yarrow’s trade secrets or proprietary information could enable competitors to duplicate or surpass Yarrow’s technological achievements, thus eroding Yarrow’s competitive position in its market. In order to protect its proprietary technology and processes, Yarrow relies in part on confidentiality agreements with its collaborators, employees, consultants, outside scientific collaborators and sponsored researchers and other advisors. These agreements may not effectively prevent disclosure of confidential information and may not provide an adequate remedy in the event of unauthorized disclosure of confidential information. Yarrow may need to share its proprietary information, including trade secrets, with future business partners, collaborators, contractors and others located in countries at heightened risk of theft of trade secrets, including through direct intrusion by private parties or state actors and those affiliated with or controlled by state actors. In addition, while Yarrow undertakes reasonable efforts to protect its trade secrets and other confidential information from disclosure, others may independently discover trade secrets and proprietary information, and in such cases, Yarrow may not be able to assert any trade secret rights against such party. Costly and time-consuming litigation could be necessary to enforce and determine the scope of Yarrow’s proprietary rights and failure to obtain or maintain trade secret protection could adversely affect Yarrow’s competitive business position.

Lastly, if Yarrow’s trademarks and trade names are not registered or adequately protected, then Yarrow may not be able to build name recognition in its markets of interest and Yarrow’s business may be adversely affected.

If Yarrow is unable to obtain or maintain necessary rights to YB-101 or its future product candidates through acquisitions and in-licenses, Yarrow’s business may be materially harmed.

Because YB-101 currently does and Yarrow’s product candidates may in the future require the use of proprietary rights held by third parties, the growth of Yarrow’s business will depend in part on its ability to acquire, in-license, or use these third-party proprietary rights. Yarrow may be unable to acquire or in-license any compositions, methods of use, processes or other third-party intellectual property rights from third parties that Yarrow identifies as necessary for its product candidates. The licensing and acquisition of third-party intellectual property rights is a competitive area, and a number of more established companies may pursue strategies to license or acquire third-party intellectual property rights that Yarrow may consider attractive or necessary. These established companies may have a competitive advantage over Yarrow due to their size, capital resources and greater clinical development and commercialization capabilities. In addition, companies that perceive Yarrow to be a competitor may be unwilling to assign or license rights to Yarrow. Yarrow also may be unable to license or acquire third-party intellectual property rights on terms that would allow Yarrow to make an appropriate return on Yarrow’s investment or at all. If Yarrow is unable to successfully obtain rights to required third-party intellectual property rights or maintain intellectual property rights Yarrow obtains in the future, Yarrow may have to abandon development of its product candidates, which could have a material adverse effect on Yarrow’s business, financial condition, results of operations, and prospects.

While Yarrow has the right to control prosecution, defense, maintenance and enforcement of patents in-licensed under the GenSci License Agreement once the trigger for transfer of prosecution control is met, there may be times when rights for patents and patent

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applications relating to Yarrow’s product candidates are controlled by Yarrow’s future licensors or collaboration partners. If Yarrow, GenSci or any of Yarrow’s future licensors or collaboration partners fail to prosecute, defend, maintain and enforce such patents and patent applications in a manner consistent with Yarrow’s best interests, including by payment of all applicable fees for patents covering its product candidates, Yarrow could lose its rights to the intellectual property or its exclusivity with respect to those rights, Yarrow’s ability to develop and commercialize those product candidates may be adversely affected and Yarrow may not be able to prevent competitors from making, using and selling competing products. In addition, even if Yarrow has the right to control prosecution of patents and patent applications Yarrow has licensed to and from third parties, including under the GenSci License Agreement following the point at which such control is assumed, Yarrow may still be adversely affected or prejudiced by actions or inactions of GenSci, additional licensees, or licensors and their counsel prior to the date upon which Yarrow assumes control over patent prosecution. For example, prior to entering into the GenSci License Agreement, GenSci was responsible for the prosecution, defense, maintenance and enforcement of patents related to YB-101. Subsequent to entering into such license agreement, subject to certain exceptions, Yarrow controls patent prosecution over YB-101 following the trigger for transfer of prosecution control to Yarrow.

Yarrow’s future licensors may not be the sole and exclusive owners of all rights in the patents Yarrow may in-license. If other third parties have rights to Yarrow’s future in-licensed patents, they may be able to license such patents to Yarrow’s competitors, and Yarrow’s competitors could market competing products and technology. This could have a material adverse effect on Yarrow’s competitive position, business, financial condition, results of operations, and prospects.

It is possible that Yarrow may be unable to obtain licenses at a reasonable cost or on reasonable terms, if at all. Even if Yarrow is able to obtain a license, it may be non-exclusive, thereby giving Yarrow’s competitors access to the same technologies licensed to Yarrow. In that event, Yarrow may be required to expend significant time and resources to redesign Yarrow’s product candidates, or the methods for manufacturing them or to develop or license replacement technology, all of which may not be feasible on a technical or commercial basis. If Yarrow is unable to do so, Yarrow may be unable to develop or commercialize the affected product candidates, which could harm Yarrow’s business, financial condition, results of operations, and prospects significantly. Yarrow cannot provide any assurances that third-party patents do not exist which might be enforced against Yarrow’s product candidates, manufacturing methods or future products or methods resulting in either an injunction prohibiting Yarrow’s manufacture or future sales, or, with respect to its future sales, an obligation on Yarrow’s part to pay royalties and/or other forms of compensation to third parties, which could be significant.

Disputes may arise between Yarrow and Yarrow’s future licensors regarding intellectual property subject to a license agreement, including (but not limited to): the scope of rights granted under the license agreement and other interpretation-related issues; whether and the extent to which Yarrow’s technology and processes infringe on intellectual property of the licensor that is not subject to the licensing agreement; Yarrow’s right to sublicense patents and other rights to third parties; Yarrow’s right to transfer or assign the license; the inventorship and ownership of inventions and know-how resulting from the joint creation or use of intellectual property by Yarrow’s future licensors and Yarrow and Yarrow’s partners; and the priority of invention of patented technology. If Yarrow or its future licensors breach the terms of Yarrow’s license agreements, such breach may have a material adverse effect on Yarrow’s business and the commercialization efforts for its product candidates.

Yarrow may be subject to intellectual property lawsuits or may need to file lawsuits to protect Yarrow’s intellectual property, which could result in substantial costs and liability and prevent Yarrow from commercializing Yarrow’s potential products.

Because the intellectual property landscape in the biotechnology industry is rapidly evolving and interdisciplinary, it is difficult to conclusively assess Yarrow’s freedom to operate and guarantee that Yarrow can operate without infringing on or violating third party rights. If certain of Yarrow’s product candidates are ultimately granted regulatory approval, patent rights held by third parties could be alleged to render one or more of Yarrow’s product candidates infringing. If a third party successfully brings a claim against Yarrow, and Yarrow’s rights are not held invalid or unenforceable, Yarrow may be required to pay substantial damages, be forced to abandon any affected product candidate and/or seek a license from the patent holder. In addition, any intellectual property claims (e.g., patent infringement or trade secret misappropriation) brought against Yarrow, whether or not successful, may cause Yarrow to incur significant legal expenses and divert the attention of Yarrow’s management and key personnel from other business concerns. Yarrow cannot be certain that future patents, if filed and issued, owned or licensed by Yarrow will not be challenged by others, whether in the course of litigation or in agencies like the USPTO. Some of Yarrow’s competitors may be able to sustain the costs of complex intellectual property litigation more effectively than Yarrow can because they have substantially greater resources. In addition, any uncertainties resulting from the initiation and continuation of any litigation could have a material adverse effect on Yarrow’s ability to raise funds.

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Competitors may infringe or otherwise violate Yarrow’s future patents, trademarks, copyrights or other intellectual property. To counter infringement or other violations, Yarrow may be required to file claims, which can be expensive and time-consuming. Any such claims could provoke these parties to assert counterclaims against Yarrow, including claims alleging that Yarrow infringe their patents or other intellectual property rights. In addition, in a patent infringement proceeding, a court or administrative body may decide that one or more of the Yarrow’s future patents, if obtained and asserted, is invalid or unenforceable, in whole or in part, construe the patent’s claims narrowly or refuse to prevent the other party from using the technology at issue on the grounds that Yarrow’s patents do not cover the technology. Similarly, if Yarrow asserts trademark infringement claims, a court or administrative body may determine that the marks Yarrow has asserted are invalid or unenforceable or that the party against whom Yarrow has asserted trademark infringement has superior rights to the marks in question. In such a case, Yarrow could ultimately be forced to cease use of such marks. In any intellectual property litigation, even if Yarrow is successful, any award of monetary damages or other remedy Yarrow receives may not be commercially valuable.

Further, Yarrow may be required to protect its future patents, if filed and issued, through procedures created to attack the validity of a patent at the USPTO. An adverse determination in any such submission or proceeding could reduce the scope or enforceability of, or invalidate, Yarrow’s patent rights, which could adversely affect Yarrow’s competitive position. Because of a lower evidentiary standard in USPTO proceedings compared to the evidentiary standard in United States federal courts necessary to invalidate a patent claim, a third party could potentially provide evidence in a USPTO proceeding sufficient for the USPTO to hold a claim invalid even though the same evidence would be insufficient to invalidate the claim if first presented in a district court action.

In addition, if Yarrow’s product candidates are found to infringe the intellectual property rights of third parties, these third parties may assert infringement claims against Yarrow’s future licensees or customers and other parties with whom Yarrow has business relationships and Yarrow may be required to indemnify those parties for any damages they suffer as a result of these claims, which may require Yarrow to initiate or defend protracted and costly litigation on behalf of licensees or other parties regardless of the merits of such claims. If any of these claims succeed, Yarrow may be forced to pay damages on behalf of those parties or may be required to obtain licenses for the products Yarrow uses.

Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation or other legal proceedings relating to Yarrow’s intellectual property rights, there is a risk that some of Yarrow’s confidential information could be compromised by disclosure during this type of litigation or other proceedings.

Yarrow’s success will depend in part on Yarrow’s and Yarrow’s current and future licensors’ ability to obtain, maintain and enforce patent protection for Yarrow’s owned and licensed intellectual property.

Yarrow’s success will depend in part on Yarrow’s and its current and future licensors’ (including GenSci’s) ability to obtain, maintain and enforce patent protection for Yarrow’s owned and licensed intellectual property. Yarrow may not successfully prosecute Yarrow’s current or future patent applications that cover Yarrow’s product candidates. Even if patents are issued that are owned by Yarrow, Yarrow may fail to maintain these patents, or may determine not to pursue litigation against other companies that are infringing these patents. After entry into the GenSci License Agreement, and once the trigger for transfer of prosecution control is met, Yarrow controls the prosecution, maintenance, enforcement and defense of licensed patent rights regarding YB-101. Prior to entering into the GenSci License Agreement, GenSci held such rights. Yarrow, GenSci and Yarrow’s future licensors may not successfully prosecute the licensed patent applications that cover Yarrow’s product candidates. Even if patents are issued in respect of these patent applications, Yarrow and Yarrow’s future licensors (including GenSci) may fail to maintain these patents, may determine not to pursue litigation against other companies that are infringing these patents, or may pursue such litigation less aggressively than Yarrow would. Without protection for any owned or in-licensed intellectual property, other companies might be able to offer substantially identical products for sale, which could adversely affect Yarrow’s competitive business position and harm Yarrow’s business prospects.

Yarrow may be subject to claims that Yarrow has wrongfully hired an employee from a competitor or that Yarrow’s employees, consultants or independent contractors have wrongfully used or disclosed confidential information of third parties.

As is common in the biotechnology industry, in addition to Yarrow’s employees, Yarrow engages the services of consultants to assist Yarrow in the development of Yarrow’s product candidates. Many of these consultants, and many of Yarrow’s employees, were previously employed at, or may have previously provided or may be currently providing consulting services to, other biotechnology or pharmaceutical companies including Yarrow’s competitors or potential competitors. Yarrow could in the future be subject to claims that Yarrow or Yarrow’s employees have inadvertently or otherwise used or disclosed alleged trade secrets or other confidential information of former employers or competitors. Although Yarrow tries to ensure that its employees and consultants do not use the

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intellectual property, proprietary information, know-how or trade secrets of others in their work for Yarrow, Yarrow may become subject to claims that it caused an employee to breach the terms of his or her non-competition or non-solicitation agreement, or that Yarrow or these individuals have, inadvertently or otherwise, used or disclosed the alleged trade secrets or other proprietary information of a former employer or competitor.

While Yarrow may litigate to defend against these claims, even if Yarrow is successful, litigation could result in substantial costs and could be a distraction to management and other employees. If Yarrow’s defenses to these claims fail, in addition to requiring Yarrow to pay monetary damages, a court could prohibit Yarrow from using technologies or features that are essential to Yarrow’s product candidates, if such technologies or features are found to incorporate or be derived from the trade secrets or other proprietary information of the former employers. Moreover, any such litigation or the threat thereof may adversely affect Yarrow’s reputation, its ability to form strategic alliances or sublicense Yarrow’s rights to collaborators, engage with scientific advisors or hire employees or consultants, each of which would have an adverse effect on Yarrow’s business, results of operations and financial condition. Even if Yarrow is successful in defending against such claims, litigation could result in substantial costs and be a distraction to management.

Changes to patent laws in the United States and other jurisdictions could diminish the value of patents in general, thereby impairing Yarrow’s ability to protect its products.

Changes in either the patent laws or interpretation of patent laws in the United States, including patent reform legislation such as the Leahy-Smith America Invents Act (the “Leahy-Smith Act”), could increase the uncertainties and costs surrounding the prosecution of Yarrow’s owned and in-licensed patent applications and the maintenance, enforcement or defense of Yarrow’s owned and in-licensed patent applications, if issued. The Leahy- Smith Act includes a number of significant changes to United States patent law. These changes include provisions that affect the way patent applications are prosecuted, redefine prior art, provide more efficient and cost-effective avenues for competitors to challenge the validity of patents, and enable third-party submission of prior art to the USPTO during patent prosecution and additional procedures to attack the validity of a patent at USPTO-administered post-grant proceedings, including post-grant review, inter partes review, and derivation proceedings. Assuming that other requirements for patentability are met, prior to March 2013, in the United States, the first to invent the claimed invention was entitled to the patent, while outside the United States, the first to file a patent application was entitled to the patent. After March 2013, under the Leahy-Smith Act, the United States transitioned to a first-to-file system in which, assuming that the other statutory requirements for patentability are met, the first inventor to file a patent application will be entitled to the patent on an invention regardless of whether a third party was the first to invent the claimed invention. As such, the Leahy-Smith Act and its implementation increased the uncertainties and costs surrounding the prosecution of Yarrow’s owned and licensed patent applications and the enforcement or defense of any resulting issued patents, all of which could have a material adverse effect on Yarrow’s business, financial condition, results of operations and prospects. Additionally, there have been proposals for additional changes to the patent laws of the United States and other countries that, if adopted, could impact Yarrow’s ability to enforce its proprietary technology.

In addition, the patent positions of companies in the development and commercialization of biologics and pharmaceuticals are particularly uncertain. U.S. Supreme Court and U.S. Court of Appeals for the Federal Circuit rulings have narrowed the scope of patent protection available in certain circumstances and weakened the rights of patent owners in certain situations, including in the antibody arts. For example, the United States Supreme Court in Amgen, Inc. v. Sanofi (“Amgen”) recently held that Amgen’s patent claims to a class of antibodies functionally defined by their ability to bind a particular antigen were invalid for lack of enablement where the patent specification provided 26 exemplary antibodies, but the claimed class of antibodies covered a “vast number” of additional antibodies not disclosed in the specification. The Court stated that if patent claims are directed to an entire class of compositions of matter, then the patent specification must enable a person skilled in the art to make and use the entire class of compositions. This decision makes it unlikely that Yarrow will be granted U.S. patents with composition of matter claims as broad as Amgen’s directed to antibodies functionally defined by their ability to bind a particular antigen. Even if Yarrow is granted claims directed to functionally defined antibodies, it is possible that a third party may challenge Yarrow’s patents, when issued, relying on the reasoning in Amgen or other precedential court decisions. This combination of events has created uncertainty with respect to the validity and enforceability of patents once obtained. Depending on future actions by the U.S. Congress, the federal courts and the USPTO, the laws and regulations governing patents could change in unpredictable ways that could have a material adverse effect on Yarrow’s patent rights and its ability to protect, defend and enforce its patent rights in the future.

In addition, the U.S. Supreme Court’s July 2024 decision to overturn established case law giving deference to regulatory agencies’ interpretations of ambiguous statutory language has introduced uncertainty regarding the extent to which the FDA’s regulations, policies and decisions may become subject to increasing legal challenges, delays, and/or changes. Yarrow cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative action, either in the United States or abroad. Geopolitical instability in the United States and in foreign countries could increase the uncertainties and costs

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surrounding the prosecution or maintenance of patent applications and the maintenance, enforcement or defense of issued patents. In addition, the Unified Patent Court (“UPC”) entered into force on June 1, 2023. The UPC is a common patent court that hears patent infringement and revocation proceedings effective for EU Member States. This could enable third parties to seek revocation of a European patent in a single proceeding at the UPC rather than through multiple proceedings in each of the jurisdictions in which the European patent is validated.

Although Yarrow does not currently own any European patents or applications, if Yarrow obtains or license such patents and applications in the future, any such revocation and loss of patent protection could have a material adverse impact on Yarrow’s business and its ability to commercialize or license its technology and products. Moreover, the controlling laws and regulations of the UPC will develop over time and may adversely affect Yarrow’s ability to enforce or defend the validity of any European patents Yarrow may obtain. Yarrow may decide to opt out from the UPC any future European patent applications that Yarrow may file and any patents Yarrow may obtain. If certain formalities and requirements are not met, however, such European patents and patent applications could be challenged for non-compliance and brought under the jurisdiction of the UPC. Yarrow cannot be certain that future European patents and patent applications will avoid falling under the jurisdiction of the UPC, if Yarrow decides to opt out of the UPC.

Obtaining and maintaining patent protection depends on compliance with various procedural, document submissions, fee payment and other requirements imposed by governmental patent agencies, and Yarrow’s patent protection could be reduced or eliminated for non-compliance with these requirements.

Periodic maintenance fees, renewal fees, annuities fees and various other governmental fees on patents and/or patent applications are due to be paid to the USPTO and foreign patent agencies in several stages over the lifetime of the patent and/or patent application. The USPTO and various foreign governmental patent agencies also require compliance with a number of procedural, documentary, fee payment and other similar provisions during the patent application process. While an inadvertent lapse can in many cases be cured by payment of a late fee or by other means in accordance with the applicable rules, there are situations in which noncompliance can result in abandonment or lapse of the patent or patent application, resulting in partial or complete loss of patent rights in the relevant jurisdiction. Non-compliance events that could result in abandonment or lapse of a patent or patent application include, but are not limited to, failure to respond to official actions within prescribed time limits, non-payment of fees and failure to properly legalize and submit formal documents. If Yarrow fails to maintain any future owned or licensed patents, if issued, or fails to maintain any current or future owned or licensed pending patent applications, covering Yarrow’s product candidates, its competitive position would be adversely affected.

Yarrow may not identify relevant third-party patents or may incorrectly interpret the relevance, scope or expiration of a third-party patent, which might adversely affect Yarrow’s ability to develop and market its products.

Yarrow cannot guarantee that any of Yarrow’s patent searches or analyses, including the identification of relevant patents, the scope of patent claims or the expiration of relevant patents, are complete or thorough, nor can Yarrow be certain that it has identified each and every third-party patent and pending application in the United States and abroad that is relevant to or necessary for the commercialization of Yarrow’s product candidates in any jurisdiction. The scope of a patent claim is determined by an interpretation of the law, the written disclosure in a patent, the patent’s prosecution history and in some cases certain extrinsic evidence of the meaning of terms in a claim. Yarrow’s interpretation of the relevance or the scope of a patent or a pending application may be incorrect. For example, Yarrow may incorrectly determine that its products are not covered by a third-party patent or may incorrectly predict whether a third-party’s pending application will issue with claims of relevant scope. Yarrow’s determination of the expiration date of any patent in the United States or abroad that Yarrow considers relevant may be incorrect. Yarrow’s failure to identify and correctly interpret relevant patents may negatively impact its ability to develop and market its products.

In addition, because some patent applications in the United States may be maintained in secrecy until the patents are issued, patent applications in the United States and many foreign jurisdictions are typically not published until 18 months after filing, and publications in the scientific literature often lag behind actual discoveries, Yarrow cannot be certain that others have not filed patent applications for technology covered by Yarrow’s current or future, owned or licensed patent applications or patents, if issued, or that Yarrow is the first to invent the technology. Yarrow’s competitors may have filed, and may in the future file, patent applications covering Yarrow’s products or technology similar to Yarrow’s. Any such patent application may have priority over Yarrow’s current or future, owned or licensed patent applications or patents, if issued, which could require Yarrow to obtain rights to issued patents covering such technologies.

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Yarrow may become subject to claims challenging the inventorship or ownership of Yarrow’s patents, if issued, and other intellectual property.

Yarrow may be subject to claims that former employees, collaborators or other third parties have an interest in Yarrow’s current pending patent application, or future patents, if filed and issued, or other intellectual property as an inventor or co- inventor. The failure to name the proper inventors on a patent application can result in the patents issuing thereon being invalid or unenforceable. Inventorship disputes may arise from conflicting views regarding the contributions of different individuals named as inventors, the effects of foreign laws where foreign nationals are involved in the development of the subject matter of the patent, conflicting obligations of third parties involved in developing Yarrow’s product candidates or as a result of questions regarding co-ownership of potential joint inventions. Litigation may be necessary to resolve these and other claims challenging inventorship and/or ownership. Alternatively, or additionally, Yarrow may enter into agreements to clarify the scope of Yarrow’s rights in such intellectual property. If Yarrow fails in defending any such claims, in addition to paying monetary damages, Yarrow may lose valuable intellectual property rights, such as exclusive ownership of, or right to use, valuable intellectual property. Such an outcome could have a material adverse effect on Yarrow’s business. Even if Yarrow is successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees.

Yarrow’s current or future licensors may have relied on third-party consultants or collaborators or on funds from third parties, such as the U.S. government, such that Yarrow’s licensors are not the sole and exclusive owners of the patents Yarrow in-licensed. If other third parties have ownership rights or other rights to Yarrow’s owned or in-licensed pending patent applications or future patents, if filed and issued, they may be able to license such patent applications or patents to Yarrow’s competitors, and its competitors could market competing products and technology. This could have a material adverse effect on Yarrow’s competitive position, business, financial condition, results of operations, and prospects.

Patent terms may be inadequate to protect Yarrow’s competitive position of its product candidates for an adequate amount of time.

Patents have a limited lifespan. In the United States, if all maintenance fees are timely paid, the natural expiration of a patent is generally 20 years from Yarrow’s earliest U.S. non-provisional filing date. Various extensions may be available, but the life of a patent, and the protection it affords, is limited. Even if patents covering Yarrow’s product candidates are obtained, once the patent life has expired, Yarrow may be open to competition from competitive products, including generics or biosimilars. Given the amount of time required for the development, testing and regulatory review of new product candidates, patents protecting such product candidates might expire before or shortly after such product candidates are commercialized. As a result, Yarrow’s owned and licensed patent portfolio may not provide Yarrow with sufficient rights to exclude others from commercializing products similar or identical to ours.

Yarrow’s technology licensed from various third parties may be subject to retained rights.

Yarrow’s future licensors may retain certain rights under the relevant agreements with Yarrow, including the right to use or license the licensed technology outside of the scope of Yarrow’s license, use the underlying technology for noncommercial academic and research use, to publish general scientific findings from research related to the technology, and to make customary scientific and scholarly disclosures of information relating to the technology. It is difficult to monitor whether Yarrow’s licensors limit their use of the technology to these uses, and Yarrow could incur substantial expenses to enforce Yarrow’s rights to its licensed technology in the event of misuse. In addition, while there are certain restrictions on GenSci’s ability to develop products that could be competitive with ours as more fully described in “Yarrow’s Business — The GenSci License Agreement” beginning on page 260 of this proxy statement/prospectus, these restrictions may not prevent the possible future license or development by GenSci of certain technology that could lead to product candidates competitive with ours. This could have a material adverse effect on Yarrow’s competitive position, business, financial condition, results of operations, and prospects.

Risks Related to Government Regulation

The regulatory approval processes of the FDA and other comparable foreign regulatory authorities are lengthy, time-consuming and inherently unpredictable. If Yarrow is not able to obtain, or if there are delays in obtaining, required regulatory approvals for Yarrow’s product candidates, Yarrow will not be able to commercialize, or will be delayed in commercializing, its product candidates, and its ability to generate revenue will be materially impaired.

The process of obtaining regulatory approvals, both in the United States and abroad, is unpredictable, expensive and typically takes many years following commencement of clinical trials, if approval is obtained at all, and can vary substantially based upon a

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variety of factors, including the type, complexity and novelty of the product candidates involved. Yarrow cannot commercialize product candidates in the United States without first obtaining regulatory approval from the FDA. Similarly, Yarrow cannot commercialize product candidates outside of the United States without obtaining regulatory approval from comparable foreign regulatory authorities. Before obtaining regulatory approvals for the commercial sale of Yarrow’s product candidates, including YB-101, Yarrow must demonstrate through lengthy, complex and expensive preclinical studies and clinical trials that its product candidates are both safe and effective for each targeted indication. Securing regulatory approval also requires the submission of information about the drug manufacturing process to, and inspection of manufacturing facilities by, the relevant regulatory authority. Further, Yarrow’s product candidates may not be effective, may be only moderately effective, may prove to have undesirable or unintended side effects, toxicities or other characteristics, or may fail to improve on the applicable standard of care, any of which may preclude Yarrow from obtaining regulatory approval. The FDA and comparable foreign regulatory authorities have discretion in the approval process and may refuse to accept any application or may decide that Yarrow’s data is insufficient for approval and require additional preclinical, clinical or other data. Yarrow’s product candidates could be delayed in receiving, or fail to receive, regulatory approval for many reasons, including: the FDA or comparable foreign regulatory authorities may disagree with the design or implementation of Yarrow’s clinical trials; Yarrow may be unable to demonstrate to the satisfaction of the FDA or comparable foreign regulatory authorities that a product candidate is safe and effective for Yarrow’s proposed indication; the results of clinical trials may not meet the level of statistical significance required by the FDA or comparable foreign regulatory authorities for approval; serious and unexpected drug-related side effects may be experienced by participants in Yarrow’s clinical trials or by individuals using drugs similar to its product candidates; Yarrow may be unable to demonstrate that a product candidate’s clinical and other benefits outweigh Yarrow’s safety risks; the FDA or comparable foreign regulatory authorities may disagree with Yarrow’s interpretation of data from preclinical studies or clinical trials; the data collected from clinical trials of Yarrow’s product candidates may not be acceptable or sufficient to support the submission of a biologics license application (“BLA”) or other submission or to obtain regulatory approval in the United States or elsewhere, and Yarrow may be required to conduct additional clinical trials; the FDA or the applicable foreign regulatory authority may disagree regarding the formulation, labeling and/or the specifications of Yarrow’s product candidates; the FDA or comparable foreign regulatory authorities may fail to approve the manufacturing processes or facilities of third-party manufacturers with which Yarrow contracts for clinical and commercial supplies; and the approval policies or regulations of the FDA or comparable foreign regulatory authorities may significantly change in a manner rendering Yarrow’s clinical data insufficient for approval.

Of the large number of drugs in development, only a small percentage successfully complete the FDA or applicable foreign regulatory approval processes and are commercialized. The lengthy approval process as well as the unpredictability of future clinical trial results may result in Yarrow failing to obtain regulatory approval to market Yarrow’s product candidates, which would significantly harm Yarrow’s business, results of operations and prospects.

If Yarrow was to obtain approval, regulatory authorities may approve any of Yarrow’s product candidates for fewer or more limited indications than Yarrow requests, including failing to approve the most commercially promising indications, may grant approval contingent on the performance of costly post- marketing clinical trials, or may approve a product candidate with a label that does not include the labeling claims necessary or desirable for the successful commercialization of that product candidate. If Yarrow is not able to obtain, or if there are delays in obtaining, required regulatory approvals for Yarrow’s product candidates, Yarrow will not be able to commercialize, or will be delayed in commercializing, this could have a material adverse effect on Yarrow’s competitive position, business, financial condition, results of operations, and prospects. In addition, the FDA and foreign regulatory authorities may undergo leadership changes, change their policies, issue additional regulations or revise existing regulations, or take other actions, such as those implemented by the Department of Government Efficiency, which may impact Yarrow’s clinical development plans or prevent or delay approval of Yarrow’s product candidates under development on a timely basis. Such policy or regulatory changes could impose additional requirements upon Yarrow that could delay Yarrow’s ability to obtain approvals and increase the costs of compliance. Since the start of President Trump’s administration in 2025, U.S. policy changes have been implemented at a rapid pace and additional changes are likely. It is difficult to predict how executive actions that may be taken under the current administration may affect the FDA’s ability to exercise its regulatory authority. If any actions impose constraints on the FDA’s ability to engage in routine oversight and product review activities in the normal course, Yarrow’s business may be negatively impacted. Additionally, federal government could adopt legislation, regulations or policies that adversely affect Yarrow’s business or create a more challenging and costly environment to pursue the development, approval and commercialization of Yarrow’s product candidates.

Yarrow may not be able to meet requirements for the chemistry, manufacturing and control of Yarrow’s product candidates.

In order to receive approval of Yarrow’s products by the FDA and comparable foreign regulatory authorities, Yarrow must show that it and Yarrow’s contract manufacturing partners are able to characterize, control and manufacture Yarrow’s drug products safely and in accordance with regulatory requirements. This includes manufacturing the active ingredient, developing an acceptable

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formulation, manufacturing the drug product, performing tests to adequately characterize the formulated product, documenting a repeatable manufacturing process, and demonstrating that Yarrow’s drug products meet stability requirements. Meeting these chemistry, manufacturing and control requirements is a complex task that requires specialized expertise. If Yarrow is not able to meet the chemistry, manufacturing and control requirements, Yarrow may not be successful in getting Yarrow’s products approved.

Yarrow’s product candidates for which Yarrow intends to seek approval as biologics may face competition from biosimilars sooner than anticipated.

The ACA includes a subtitle called the Biologics Price Competition and Innovation Act of 2009 (“BPCIA”), which created an abbreviated approval pathway for biological products that are biosimilar to or interchangeable with an FDA-licensed reference biological product. Under the BPCIA, an application for a highly similar or “biosimilar” product may not be submitted to the FDA until four years following the date that the reference product was first approved by the FDA. In addition, the approval of a biosimilar product may not be made effective by the FDA until 12 years from the date on which the reference product was first approved. During this 12-year period of exclusivity, another company may still market a competing version of the reference product if the FDA approves a full BLA for the competing product containing the sponsor’s own preclinical data and data from adequate and well-controlled clinical trials to demonstrate the safety, purity and potency of their product.

Yarrow believes that any of Yarrow’s product candidates approved as biologics under a BLA should qualify for the 12-year period of exclusivity. However, there is a risk that this exclusivity could be shortened due to congressional action or otherwise, or that the FDA will not consider Yarrow’s product candidates to be reference products for competing products, potentially creating the opportunity for competition sooner than anticipated. Other aspects of the BPCIA, some of which may impact the BPCIA exclusivity provisions, have also been the subject of recent litigation. Moreover, the extent to which a biosimilar, once approved, will be substituted for any reference products in a way that is similar to traditional generic substitution for non- biological products is not yet clear, and will depend on a number of marketplace and regulatory factors that are still developing.

Even if Yarrow receives regulatory approval of Yarrow’s product candidates, Yarrow will be subject to extensive ongoing regulatory obligations and continued regulatory review, which may result in significant additional expense, and Yarrow may be subject to penalties if it fails to comply with regulatory requirements or experience unanticipated problems with its product candidates.

Any regulatory approvals that Yarrow may receive for Yarrow’s product candidates will require the submission of reports to regulatory authorities and surveillance to monitor the safety and efficacy of the product candidate, may contain significant limitations related to use restrictions for specified age groups, warnings, precautions or contraindications, and may include burdensome post-approval study or risk management requirements. For example, the FDA may require a risk evaluation and mitigation strategy (“REMS”) in order to approve Yarrow’s product candidates, which could entail requirements for a medication guide, physician training and communication plans or additional elements to ensure safe use, such as restricted distribution methods, patient registries and other risk minimization tools. Comparable foreign regulatory authorities may impose similar requirements. In addition, if the FDA or comparable foreign regulatory authorities approve Yarrow’s product candidates, Yarrow’s product candidates and the activities associated with their development and commercialization, including their design, testing, manufacture, safety, efficacy, recordkeeping, labeling, storage, approval, advertising, promotion, sale, distribution, import and export will be subject to comprehensive regulation by the FDA and other regulatory agencies in the United States and by comparable foreign regulatory authorities. These requirements include submissions of safety and other post-marketing information and reports, registration, as well as on-going compliance with cGMPs and GCPs for any clinical trials that Yarrow conducts following approval. In addition, manufacturers of drug products and their facilities are subject to continual review and periodic, unannounced inspections by the FDA and other regulatory authorities for compliance with cGMPs. If Yarrow or a regulatory authority discovers previously unknown problems with a product, such as adverse events of unanticipated severity or frequency, or problems with the facilities where the product is manufactured, a regulatory authority may impose restrictions on that product, the manufacturing facility or Yarrow, including requiring recall or withdrawal of the product from the market or suspension of manufacturing, delays or restrictions on Yarrow’s ability to conduct clinical trials or delays or refusal to grant a marketing authorization, including full or partial clinical holds on ongoing or planned trials, restrictions on the manufacturing process, warning or untitled letters, civil and criminal penalties, injunctions, product seizures, detentions or import bans, suspension, withdrawal or variation of any marketing authorization that has been granted, voluntary or mandatory publicity requirements and imposition of restrictions on operations, including costly new manufacturing requirements. Similar penalties may apply in case of failure by Yarrow or by any of Yarrow’s third-party partners, including suppliers, manufacturers and distributors, to comply with FDA and EU laws and the related national laws of individual EU Member States and other applicable regulatory authorities governing the conduct of clinical trials, manufacturing approval, marketing authorization of medicinal products and marketing of such products, both before and after grant of a marketing authorization, statutory health insurance, bribery and anti-

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corruption or other applicable regulatory requirements, including administrative, civil or criminal penalties. The occurrence of any event or penalty described above may inhibit Yarrow’s ability to commercialize its product candidates and generate revenue and could require Yarrow to expend significant time and resources in response and could generate negative publicity.

Disruptions at the FDA, the SEC and other government agencies and regulatory authorities caused by funding shortages or global health concerns could hinder their ability to hire and retain key leadership and other personnel, prevent new products and services from being developed or commercialized in a timely manner or otherwise prevent those agencies from performing normal business functions on which the operation of Yarrow’s business may rely, which could negatively impact its business.

The ability of the FDA to review regulatory filings and Yarrow’s ability to commence human clinical trials can be affected by a variety of factors, including government budget and funding levels, ability to hire and retain key personnel and accept the payment of user fees, and statutory, regulatory and policy changes. Average review times at the agency have fluctuated in recent years as a result. In addition, government funding of the SEC, and other government agencies on which Yarrow’s operations may rely, including those that fund research and development activities is subject to the political process, which is inherently fluid and unpredictable.

Disruptions at the FDA and other agencies or comparable foreign regulatory authorities may also slow the time necessary for the review and approval of applications for clinical trial or marketing authorization, which would adversely affect Yarrow’s business. For example, in recent years, including in 2018, 2019 and 2025, the U.S. government shut down several times and certain regulatory agencies, such as the FDA and the SEC, had to furlough critical employees and stop critical activities. Additionally, action by the Trump administration to limit federal agency budgets or personnel may result in reductions to the FDA’s budget, employees, and operations, which may lead to slower response times and longer review periods, potentially affecting Yarrow’s ability to progress development of its product candidates or obtain regulatory approval for its product candidates. If a prolonged government shutdown occurs, it could significantly impact the ability of the FDA to timely review and process Yarrow’s regulatory submissions, which could have a material adverse effect on its business. Further, future government shutdowns could impact Yarrow’s ability to access the public markets and obtain necessary capital in order to properly capitalize and continue Yarrow’s operations.

If a prolonged government shutdown occurs, or if global health concerns prevent the FDA or other regulatory authorities from conducting their regular inspections, reviews, or other regulatory activities, it could significantly impact the ability of the FDA or other regulatory authorities to timely review and process Yarrow’s regulatory submissions, which could have a material adverse effect on Yarrow’s business.

Yarrow may face difficulties from healthcare and regulatory legislative reform measures.

Existing regulatory policies may change, and additional government regulations may be enacted that could prevent, limit or delay regulatory approval of Yarrow’s product candidates. Yarrow cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative action, either in the United States or abroad. For example, the Trump administration has discussed several changes to the reach and oversight of the FDA, which could affect its relationship with the pharmaceutical industry, transparency in decision making and ultimately the cost and availability of prescription drugs. If Yarrow is slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if Yarrow is not able to maintain regulatory compliance, Yarrow may lose any regulatory approval that it may have obtained and it may not achieve or sustain profitability.

Yarrow’s business operations and current and future arrangements with investigators, healthcare professionals, consultants, third-party payors, patient organizations and customers will be subject to applicable healthcare regulatory laws, which could expose Yarrow to penalties.

Yarrow’s business operations and current and future arrangements with investigators, healthcare professionals, consultants, third-party payors, patient organizations and customers may expose Yarrow to broadly applicable fraud and abuse and other healthcare laws and regulations. These laws may constrain the business or financial arrangements and relationships through which Yarrow conducts its operations, including how it researches, markets, sells and distributes its product candidates, if approved.

Ensuring that Yarrow’s internal operations and future business arrangements with third parties comply with applicable healthcare laws and regulations will involve substantial costs. If Yarrow’s operations are found to be in violation of any of these laws or any other governmental laws and regulations that may apply to Yarrow, it may be subject to significant penalties, including civil, criminal and administrative penalties, damages, fines, exclusion from government-funded healthcare programs, integrity oversight and reporting obligations to resolve allegations of non-compliance, disgorgement, individual imprisonment, contractual damages,

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reputational harm, diminished profits and the curtailment or restructuring of Yarrow’s operations. Further, defending against any such actions can be costly and time-consuming and may require significant personnel resources. Therefore, even if Yarrow is successful in defending against any such actions that may be brought against it, Yarrow’s business may be impaired.

Even if Yarrow is able to commercialize any product candidates, due to unfavorable pricing regulations and/or third-party coverage and reimbursement policies, Yarrow may not be able to offer such product candidates at competitive prices, which would seriously harm Yarrow’s business.

Yarrow intends to seek approval to market Yarrow’s product candidates in both the United States and in selected foreign jurisdictions. If Yarrow obtains approval in one or more foreign jurisdictions for Yarrow’s product candidates, Yarrow will be subject to rules and regulations in those jurisdictions. Yarrow’s ability to successfully commercialize any product candidates that Yarrow may develop will depend in part on the extent to which reimbursement for these product candidates and related treatments will be available from government health administration authorities, private health insurers and other organizations. Government authorities and other third-party payors, such as private health insurers and health maintenance organizations, decide which medications they will pay for and establish reimbursement levels. Government authorities and other third-party payors have attempted to control costs by limiting coverage and the amount of reimbursement for particular medications. These entities may create preferential access policies for a competitor’s product, including a branded or generic/biosimilar product, over Yarrow’s products in an attempt to reduce their costs, which may reduce Yarrow’s commercial opportunity.

Yarrow is subject to U.S. and certain foreign export and import controls, sanctions, embargoes, anti-corruption laws, and anti-money laundering laws and regulations. Yarrow can face criminal liability and other serious consequences for violations, which can harm Yarrow’s business.

Yarrow is subject to export control and import laws and regulations, including the U.S. Export Administration Regulations, U.S. Customs regulations, various economic and trade sanctions regulations administered by the U.S. Treasury Department’s Office of Foreign Assets Controls, the U.S. Foreign Corrupt Practices Act of 1977, as amended, the U.S. domestic bribery statute contained in 18 U.S.C. § 201, the U.S. Travel Act, the USA PATRIOT Act, and other state and national anti-bribery and anti-money laundering laws in the countries in which Yarrow conducts activities. Governmental regulation of the import or export of Yarrow’s drug candidates, or Yarrow’s failure to obtain any required import or export authorization for its candidates, when applicable, could harm international operations. Furthermore, export control laws and economic sanctions prohibit the provision of certain items, technology, and services to countries, governments, and persons targeted by sanctions programs. Anti-corruption laws are interpreted broadly and prohibit companies and their employees, agents, contractors, and other collaborators from authorizing, promising, offering, or providing, directly or indirectly, improper payments or anything else of value to or from recipients in the public or private sector. Yarrow may engage third parties to sell Yarrow’s products outside the United States, to conduct clinical trials, and/or to obtain necessary permits, licenses, patent registrations, and other regulatory approvals. Yarrow has direct or indirect interactions with officials and employees of government agencies or government-affiliated hospitals, universities, and other organizations. Yarrow can be held liable for the corrupt or other illegal activities of Yarrow’s employees, agents, contractors, and other collaborators, even if Yarrow does not explicitly authorize or have actual knowledge of such activities. Any violations of the laws and regulations described above may result in substantial civil and criminal fines and penalties, imprisonment, the loss of export or import privileges, debarment, tax reassessments, breach of contract and fraud litigation, reputational harm, and other consequences.

Governments outside the United States tend to impose strict price controls, which may adversely affect Yarrow’s revenue, if any.

In some countries, particularly EU Member States, the pricing of prescription drugs is subject to governmental control. In these countries, pricing negotiations with governmental authorities can take considerable time after receipt of regulatory approval for a therapeutic. In addition, there can be considerable pressure by governments and other stakeholders on prices and reimbursement levels, including as part of cost containment measures. Political, economic and regulatory developments may further complicate pricing negotiations, and pricing negotiations may continue after reimbursement has been obtained. Reference pricing used by various EU Member States and parallel distribution, or arbitrage between low-priced and high- priced EU Member States, can further reduce prices. To obtain coverage and reimbursement or pricing approvals in some countries, Yarrow or future collaborators may be required to conduct a clinical trial or other studies that compare the cost-effectiveness of Yarrow’s product candidates to other available therapies in order to obtain or maintain reimbursement or pricing approval. Publication of discounts by third-party payors or authorities may lead to further pressure on the prices or reimbursement levels within the country of publication and other countries. If reimbursement of any product candidate approved for marketing is unavailable or limited in scope or amount, or if pricing is set at unsatisfactory levels, Yarrow’s business, financial condition, results of operations or prospects could be materially and adversely affected.

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If Yarrow seeks and is unable to obtain accelerated approval, the amount, size and duration of Yarrow’s clinical trials could be greater than planned, which could increase the expense, reduce the likelihood, and/or delay the timing of obtaining necessary regulatory approvals. Even if Yarrow receives accelerated approval, if confirmatory trials do not verify clinical benefit, or if Yarrow does not comply with rigorous post-approval requirements, such authorities may withdraw accelerated approval.

Yarrow may seek accelerated approval, or other expedited development, review or approval status, for Yarrow’s product candidates. Even if granted, there is no guarantee that receiving an expedited development, review or approval status from the FDA will lead to a faster development or regulatory review or approval process, and such status does not increase the likelihood that Yarrow’s product candidates will ultimately receive marketing approval. The FDA may grant accelerated approval to a product designed to treat a serious or life-threatening condition that provides meaningful therapeutic advantage over available therapies and demonstrates an effect on a surrogate endpoint or intermediate clinical endpoint that is reasonably likely to predict clinical benefit. If Yarrow chooses to pursue accelerated approval, there can be no assurance that the FDA will agree that Yarrow’s proposed primary endpoint is an appropriate surrogate endpoint. Similarly, there can be no assurance that after subsequent FDA feedback that Yarrow will continue to pursue accelerated approval or any other form of expedited development, review, or approval, even if Yarrow initially decides to do so. Furthermore, if Yarrow submits an application for accelerated approval, there can be no assurance that such application will be accepted or that approval will be granted on a timely basis, or at all. The FDA also could require Yarrow to conduct further studies or trials prior to considering Yarrow’s application or granting approval of any type. Yarrow might not be able to fulfill the FDA’s requirements in a timely manner, which would cause delays, or approval might not be granted because Yarrow’s submission is deemed incomplete by the FDA. Accelerated approval may be contingent on the sponsor’s agreement to conduct, in a diligent manner, additional post-approval confirmatory studies to verify and describe the drug’s predicted effect on irreversible morbidity or mortality or other clinical benefit. Under the Food and Drug Omnibus Reform Act of 2022, the FDA may require, as appropriate, that such studies be underway prior to approval or within a specific time period after the date of approval for a product granted accelerated approval. The FDA may require that any such confirmatory study be initiated or substantially underway prior to the submission of an application for accelerated approval. Even if Yarrow receives accelerated approval from the FDA, Yarrow will be subject to rigorous post-approval requirements, including submission to the FDA of all promotional materials prior to their dissemination. The FDA could withdraw accelerated approval for multiple reasons, including Yarrow’s failure to conduct any required post-approval study with due diligence, or the inability of such study to confirm the drug’s predicted clinical benefit relative to its risks. A failure to obtain accelerated approval or any other form of expedited review or approval for a product candidate could result in a longer time period prior to commercializing such product candidate, increase the cost of development of such product candidate, and harm Yarrow’s competitive position in the marketplace. Comparable considerations apply outside of the United States.

General Risk Factors

Yarrow may become exposed to costly and damaging liability claims, when testing a product candidate in the clinical stage or at the commercial stage, and Yarrow’s product liability insurance may not cover all damages from such claims.

Yarrow is exposed to potential product liability and professional indemnity risks that are inherent in the research, development, manufacturing, marketing and use of pharmaceutical products. While Yarrow currently has no products that have been approved for commercial sale, the future use of a product candidate in clinical trials, and the sale of any approved products in the future, may expose Yarrow to liability claims. These claims may be made by patients that use the product or product candidate, healthcare providers, pharmaceutical companies, or others selling such product. Any claims against Yarrow, regardless of their merit, could be difficult and costly to defend and could materially and adversely affect the market for Yarrow’s products or any prospects for commercialization of Yarrow’s products. Although Yarrow intends to obtain product liability insurance for Yarrow’s future clinical trials, it is possible that its liabilities could exceed Yarrow’s insurance coverage or that in the future Yarrow may not be able to maintain insurance coverage at a reasonable cost or obtain insurance coverage that will be adequate to satisfy any liability that may arise. If a successful product liability claim or series of claims is brought against Yarrow for uninsured liabilities or in excess of insured liabilities, Yarrow’s assets may not be sufficient to cover such claims and Yarrow’s business operations could be impaired.

Litigation costs and the outcome of litigation could have a material adverse effect on Yarrow’s business.

From time to time, Yarrow may be subject to litigation claims through the ordinary course of Yarrow’s business operations regarding, but not limited to, securities litigation, employment matters, security of patient and employee personal information, contractual relations with collaborators and licensors and intellectual property rights. Litigation to defend Yarrow against claims by third parties, or to enforce any rights that Yarrow may have against third parties, could result in substantial costs and diversion of Yarrow’s resources, causing a material adverse effect on Yarrow’s business, financial condition, results of operations or cash flows.

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Yarrow’s business could be adversely affected by economic downturns, inflation, fluctuating interest rates, natural disasters, public health crises, political crises, geopolitical events, or other macroeconomic conditions, which could have a material and adverse effect on Yarrow’s results of operations and financial condition.

The global economy, including credit and financial markets, has experienced extreme volatility and disruptions, including, among other things, diminished liquidity and credit availability, declines in consumer confidence, declines in economic growth, supply chain shortages, increases in inflation rates, fluctuating interest rates, and uncertainty about economic stability. Adverse macroeconomic conditions, including inflation, slower growth or recession, new or increased tariffs imposed by the U.S. government and potential retaliatory measures by foreign governments and other barriers to trade, especially in light of recent comments and executive orders made by the Trump administration, changes to fiscal and monetary policy or government budget dynamics (particularly in the pharmaceutical and biotech areas), government shutdowns, tighter credit, higher interest rates, volatility in financial markets, high unemployment, labor availability constraints, currency fluctuations and other challenges in the global economy have in the past adversely affected, and may in the future adversely affect, Yarrow and its business partners and suppliers.

Since February 2025, the United States government has imposed various tariffs on imports from most countries, including tariffs on imports from China and South Korea. In September 2025, President Trump announced plans to impose 100% tariffs on imported branded or patented pharmaceuticals, unless the importing company is building U.S. manufacturing capacity, although the effective date of such tariffs has been delayed. Certain major drug producers and manufacturers are in negotiations with the U.S. Presidential Administration to receive relief from such tariffs. As a result of these negotiations, certain manufacturers, such as Pfizer, have announced their participation in a new direct purchasing platform called “TrumpRx.gov,” which allows U.S. patients to purchase certain medicines at significant discounts to current retail prices. These discounts may adversely affect revenue generated from participating drugs. The potential impact of this platform on Yarrow’s business is unclear at this time. It is not yet clear whether these tariffs would apply to the importation of active pharmaceutical ingredients and possibly bulk drug products that are intended for use in clinical trials and not for commercial sale, which could increase the costs of materials for Yarrow’s clinical trials. There still remains substantial uncertainty about the duration of existing tariffs and whether additional tariffs may be imposed, modified or suspended. Historically, tariffs have led to increased trade and political tensions. In response to tariffs, other countries have implemented retaliatory tariffs on U.S. goods. Uncertainty and political tensions as a result of trade policies could reduce trade volume, investment, technological exchange and other economic activities between major international economies, resulting in a material adverse effect on global economic conditions and the stability of global financial markets. The Federal Reserve has raised interest rates multiple times in recent years in response to concerns about inflation and, although it has lowered interest rates, there is no guarantee that it will not raise them again. High interest rates, coupled with reduced government spending and volatility in financial markets, may increase economic uncertainty and affect consumer spending. Similarly, the ongoing military conflict between Russia and Ukraine and in the Middle East and rising tensions with China have created extreme volatility in the global capital markets and may have further global economic consequences, including disruptions of the global supply chain. Any such volatility and disruptions may adversely affect Yarrow’s business or the third parties on whom Yarrow relies. If the equity and credit markets deteriorate, including as a result of political unrest or war, it may make any necessary debt or equity financing more costly, more dilutive, or more difficult to obtain in a timely manner or on favorable terms, if at all. Increased inflation rates can adversely affect Yarrow by increasing its costs, including labor and employee benefit costs.

Yarrow may in the future experience disruptions as a result of such macroeconomic conditions, including delays or difficulties in initiating or expanding clinical trials and manufacturing sufficient quantities of materials. Any one or a combination of these events could have a material and adverse effect on Yarrow’s results of operations and financial condition.

Risks Related to the Combined Company

If any of the events described in “Risks Related to VYNE” or “Risks Related to Yarrow” occur, those events could cause potential benefits of the Merger not to be realized.

Following completion of the Merger, the Combined Company will be susceptible to many of the risks described in the sections herein entitled “Risks Related to VYNE” and “Risks Related to Yarrow.” To the extent any of the events in the risks described in those sections occur, the potential benefits of the Merger may not be realized and the results of operations and financial condition of the Combined Company could be adversely affected in a material way. This could cause the market price of the Combined Company common stock to decline.

The market price of the Combined Company common stock is expected to be volatile, and the market price of the common stock may drop following the Merger.

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The market price of the Combined Company common stock following the Merger could be subject to significant fluctuations. Some of the factors that may cause the market price of the Combined Company common stock to fluctuate include:

Moreover, the stock markets in general have experienced substantial volatility that has often been unrelated to the operating performance of individual companies. These broad market fluctuations may also adversely affect the trading price of the Combined Company common stock. In addition, a recession, depression or other sustained adverse market event could materially and adversely affect the Combined Company’s business and the value of its common stock. In the past, following periods of volatility in the market price of a company’s securities, stockholders have often instituted class action securities litigation against such companies.

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Furthermore, market volatility may lead to increased shareholder activism if the Combined Company experiences a market valuation that activists believe is not reflective of its intrinsic value. Activist campaigns that contest or conflict with the Combined Company’s strategic direction or seek changes in the composition of its board of directors could have an adverse effect on its operating results, financial condition and cash flows.

The Combined Company may incur losses for the foreseeable future and may never achieve profitability.

The Combined Company may never become profitable, even if it is able to complete clinical development for one or more product candidates and eventually commercialize such product candidates. The Combined Company will need to successfully complete significant research, development, testing and regulatory compliance activities that, together with projected general and administrative expenses, are expected to result in substantial increased operating losses for at least the next several years. Even if the Combined Company does achieve profitability, it may not be able to sustain or increase profitability on a quarterly or annual basis.

If the Combined Company fails to attract and retain management and other key personnel, it may be unable to continue to successfully develop or commercialize its product candidates or otherwise implement its business plan.

The Combined Company’s ability to compete in the highly competitive pharmaceuticals industry depends on its ability to attract and retain highly qualified managerial, scientific, medical, legal, sales and marketing and other personnel. The Combined Company will be highly dependent on its management and scientific personnel. The loss of the services of any of these individuals could impede, delay, or prevent the successful development of the Combined Company’s product pipeline, completion of its planned clinical trials, commercialization of its product candidates or in-licensing or acquisition of new assets and could impact negatively its ability to implement successfully its business plan. If the Combined Company loses the services of any of these individuals, it might not be able to find suitable replacements on a timely basis or at all, and its business could be harmed as a result. The Combined Company might not be able to attract or retain qualified management and other key personnel in the future due to the intense competition for qualified personnel among biotechnology, pharmaceutical and other businesses.

The Combined Company will need to raise additional financing in the future to fund its operations, which may not be available to it on favorable terms or at all.

The Combined Company will require substantial additional funds to conduct the costly and time- consuming clinical efficacy trials necessary to pursue regulatory approval of each potential product candidate and to continue the development of YB-101 and Yarrow’s future product candidates. The Combined Company’s future capital requirements will depend upon a number of factors, including: the number and timing of future product candidates in the pipeline; progress with and results from preclinical testing and clinical trials; the ability to manufacture sufficient drug supplies to complete preclinical and clinical trials; the costs involved in preparing, filing, acquiring, prosecuting, maintaining and enforcing patent and other intellectual property claims; and the time and costs involved in obtaining regulatory approvals and favorable reimbursement or formulary acceptance. Raising additional capital may be costly or difficult to obtain and could, for example, through the sale of common stock or securities convertible or exchangeable into common stock, significantly dilute the Combined Company’s stockholders’ ownership interests or inhibit the Combined Company’s ability to achieve its business objectives. If the Combined Company raises additional funds through public or private equity offerings, the terms of these securities may include liquidation or other preferences that adversely the rights of its common stockholders. In addition, any debt financing may subject the Combined Company to fixed payment obligations and covenants limiting or restricting its ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends. If the Combined Company raises additional capital through marketing and distribution arrangements or other collaborations, strategic alliances or licensing arrangements with third parties, the Combined Company may have to relinquish certain valuable intellectual property or other rights to its product candidates, technologies, future revenue streams or research programs or grant licenses on terms that may not be favorable to it. Even if the Combined Company were to obtain sufficient funding, there can be no assurance that it will be available on terms acceptable to the Combined Company or its stockholders.

The Combined Company will incur additional costs and increased demands upon management as a result of complying with the laws and regulations affecting public companies.

The Combined Company will incur significant legal, accounting and other expenses as a public company that Yarrow did not incur as a private company, including costs associated with public company reporting obligations under the Exchange Act. The Combined Company’s management team will consist of the executive officers of Yarrow prior to the Merger. These executive officers and other personnel will need to devote substantial time to gaining expertise related to public company reporting requirements and compliance with applicable laws and regulations to ensure that the Combined Company complies with all of these requirements. Any

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changes the Combined Company makes to comply with these obligations may not be sufficient to allow it to satisfy its obligations as a public company on a timely basis, or at all. These reporting requirements, rules and regulations, coupled with the increase in potential litigation exposure associated with being a public company, could also make it more difficult for the Combined Company to attract and retain qualified persons to serve on the board of directors or on board committees or to serve as executive officers, or to obtain certain types of insurance, including directors’ and officers’ insurance, on acceptable terms.

Upon completion of the Merger, failure by the Combined Company to comply with the initial listing standards of Nasdaq will prevent its stock from being listed on Nasdaq.

Upon completion of the Merger, VYNE, under the new name “Yarrow Bioscience, Inc.” will be required to meet the initial listing requirements to maintain the listing and continued trading of its shares on Nasdaq. These initial listing requirements are more difficult to achieve than the continued listing requirements. Pursuant to the Merger Agreement, VYNE agreed to use its commercially reasonable efforts to cause the shares of VYNE Common Stock being issued in the Merger (including any common stock issuable upon the exercise of VYNE Pre-Funded Warrants) to be approved for listing on Nasdaq at or prior to the effective time of the Merger. Based on information currently available to VYNE, VYNE anticipates that its stock will be unable to meet the $4.00 minimum bid price initial listing requirement at the Closing unless it effects a reverse stock split. Based on the recent trading prices of VYNE Common Stock, VYNE and Yarrow currently estimate that a reverse stock split ratio of at least 1-for-     would be required to increase the per-share market price to $4.00, which is the minimum initial listing price requirement of Nasdaq. The final reverse stock split ratio will be determined mutually by the VYNE board of directors and the Yarrow board of directors prior to the closing of the Merger based primarily on the then-current trading price of VYNE Common Stock and the objective of achieving a post-closing per-share price that (1) satisfies Nasdaq’s listing requirements and (2) provides an appropriate and sustainable post-closing per-share market price that the parties believe will better position the Combined Company for long-term trading stability, investor interest and market visibility, taking into account prevailing market conditions and other relevant factors. Accordingly, the ratio effected is likely to be greater than the minimum necessary to satisfy Nasdaq’s listing standards. In addition, often a reverse stock split will not result in a trading price for the affected common stock that is proportional to the ratio of the split. Following the Merger, if the Combined Company is unable to satisfy Nasdaq listing requirements, Nasdaq may notify the Combined Company that its shares of common stock will not be listed on Nasdaq.

Upon a potential delisting from Nasdaq, if the Combined Company common stock is not then eligible for quotation on another market or exchange, trading of the shares could be conducted in the over-the- counter market or on an electronic bulletin board established for unlisted securities such as the Pink Sheets or the OTC Bulletin Board. In such event, it is likely that there would be significantly less liquidity in the trading of the Combined Company common stock; decreases in institutional and other investor demand for the shares, coverage by securities analysts, market making activity and information available concerning trading prices and volume; and fewer broker dealers willing to execute trades in the Combined Company common stock. Also, it may be difficult for the Combined Company to raise additional capital if the Combined Company common stock is not listed on a major exchange. The occurrence of any of these events could result in a further decline in the market price of the Combined Company common stock and could have a material adverse effect on the Combined Company.

The Combined Company is expected to be eligible to report as a “smaller reporting company,” and as a result of the reduced reporting requirements applicable to such companies, the Combined Company’s securities may be less attractive to investors.

The Combined Company is expected to be eligible to report as a smaller reporting company. For as long as the Combined Company continues to be eligible to report as a “smaller reporting company,” it may take advantage of exemptions from various reporting requirements that are applicable to other public companies that are not “smaller reporting companies,” including not being required to comply with the auditor attestation requirements in the assessment of the Combined Company’s internal control over financial reporting, as well as reduced disclosure obligations regarding executive compensation in the Combined Company’s periodic reports, proxy statements and registration statements. The Combined Company may take advantage of these reporting exemptions until it is no longer a smaller reporting company. The Combined Company will remain a smaller reporting company until the last day of any fiscal year for so long as either (1) the market value of shares of Combined Company common stock held by non-affiliates does not equal or exceed $250.0 million as of the prior June 30th, or (2) the Combined Company’s annual revenues did not equal or exceed $100.0 million during such completed fiscal year and the market value of shares of Combined Company common stock held by non-affiliates did not equal or exceed $700.0 million as of the prior June 30th.

The Combined Company will not be able to predict if investors will find Combined Company common stock less attractive because it will rely on these exemptions. If some investors find the Combined Company’s securities less attractive because it relies on

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any of these exemptions, there may be a less active trading market for the Combined Company’s common stock and the price of the Combined Company common stock may be more volatile.

Once the Combined Company is no longer a smaller reporting company or otherwise no longer qualifies for applicable exemptions, the Combined Company will be subject to additional laws and regulations affecting public companies that will increase the Combined Company’s costs and the demands on management and could harm the Combined Company’s operating results and cash flows.

The Combined Company will be subject to the reporting requirements of the Exchange Act, which requires, among other things, that the Combined Company file with the SEC, annual, quarterly and current reports with respect to the Combined Company’s business and financial condition as well as other disclosure and corporate governance requirements. However, as a “smaller reporting company,” as such term is defined in Rule 12b-2 under the Exchange Act, in at least the near term, the Combined Company may take advantage of exemptions from disclosure requirements and reduced disclosure obligations regarding executive compensation in this proxy statement/prospectus and in the Combined Company’s periodic reports and proxy statements. In addition, if the Combined Company is a smaller reporting company with less than $100.0 million in annual revenue, it would not be required to comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act. Once the Combined Company is no longer a smaller reporting company or otherwise no longer qualifies for these exemptions, the Combined Company will be required to comply with these additional legal and regulatory requirements applicable to public companies and will incur significant legal, accounting and other expenses to do so. If the Combined Company is not able to comply with the requirements in a timely manner or at all, the Combined Company’s financial condition or the market price of the Combined Company common stock may be harmed. For example, if the Combined Company or its independent auditor identifies deficiencies in the Combined Company’s internal control over financial reporting that are deemed to be material weaknesses the Combined Company could face additional costs to remedy those deficiencies, the market price of the Combined Company’s stock could decline or the Combined Company could be subject to sanctions or investigations by the SEC or other regulatory authorities, which would require additional financial and management resources.

If the Combined Company fails to maintain proper and effective internal controls, its ability to produce accurate financial statements on a timely basis could be impaired.

Provided the Combined Company continues to be listed on Nasdaq, the Combined Company will be subject to the reporting requirements of the Exchange Act, the Sarbanes-Oxley Act and the rules and regulations of Nasdaq. The Sarbanes-Oxley Act requires, among other things, that the Combined Company maintain effective disclosure controls and procedures and internal control over financial reporting. The Combined Company must perform system and process evaluation and testing of its internal control over financial reporting to allow management to report on the effectiveness of its internal controls over financial reporting in its Annual Report on Form 10-K filing for that year, as required by Section 404 of the Sarbanes- Oxley Act. As a private company, Yarrow has not been required to document and test its internal controls over financial reporting nor has its management been required to certify the effectiveness of its internal controls and its auditors have not been required to opine on the effectiveness of its internal control over financial reporting. Following the Merger, the Combined Company will be required to incur substantial professional fees and internal costs to expand its accounting and finance functions and expend significant management efforts. The Combined Company may experience difficulty in meeting these reporting requirements in a timely manner.

The Combined Company may discover weaknesses in its system of internal financial and accounting controls and procedures that could result in a material misstatement of its financial statements. The Combined Company’s internal control over financial reporting will not prevent or detect all errors and all fraud. A control system, no matter how well designed and operated, can provide only reasonable, not absolute, assurance that the control system’s objectives will be met. Because of the inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that misstatements due to error or fraud will not occur or that all control issues and instances of fraud will be detected.

If the Combined Company is not able to comply with the requirements of Section 404 of the Sarbanes- Oxley Act, or if it is unable to maintain proper and effective internal controls, the Combined Company may not be able to produce timely and accurate financial statements. If that were to happen, the market price of its common stock could decline and it could be subject to sanctions or investigations by Nasdaq, the SEC or other regulatory authorities.

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VYNE and Yarrow expect the Combined Company to amend its bylaws to provide that, unless the Combined Company consents in writing to the selection of an alternative forum, certain designated courts will be the sole and exclusive forum for certain legal actions between the Combined Company and its stockholders, which could limit its stockholders’ ability to obtain a favorable judicial forum for disputes with the Combined Company or its directors, officers, employees or stockholders.

VYNE and Yarrow expect the Combined Company to amend its bylaws to provide that, unless the Combined Company consents in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware (or, if the Court of Chancery does not have jurisdiction, or declines to accept, the federal district court for the District of Delaware or other state courts of the State of Delaware) is the sole and exclusive forum for the following types of proceedings (i) any derivative action or proceeding brought on the Combined Company’s behalf, (ii) any action asserting a claim of or based on a breach of a fiduciary duty owed by any of the Combined Company’s current or former directors, officers, employees or stockholders to the Combined Company or its stockholders, (iii) any action asserting a claim arising pursuant to any provision of the DGCL or as to which the DGCL confers jurisdiction on the Court of Chancery of the State of Delaware or (iv) any action asserting a claim arising pursuant to any provision of the Combined Company’s certificate of incorporation or its bylaws (in each case, as they may be amended from time to time) or that is governed by the internal affairs doctrine, in each case subject to the Court of Chancery having personal jurisdiction over the indispensable parties named as defendants therein, which for purposes of this risk factor refers to herein as the “Delaware Forum Provision.” The Delaware Forum Provision will not apply to any causes of action arising under the Securities Act and the Exchange Act. VYNE and Yarrow expect the Combined Company to also amend its bylaws to provide that, unless it consents in writing to an alternative forum, federal district courts of the United States will be the sole and exclusive forum for any complaint asserting a cause of action arising under the Securities Act, which for purposes of this risk factor is referred to herein as the “Federal Forum Provision.” There is uncertainty as to whether a court would enforce such a provision. The Federal Forum Provision will not apply to any causes of action arising under the Exchange Act. In addition, the bylaws of the Combined Company will provide that any person or entity purchasing or otherwise acquiring or holding any interest in shares of its capital stock is deemed to have notice of and consented to the foregoing Delaware Forum Provision and Federal Forum Provision; provided, however, that stockholders cannot and will not be deemed to have waived the Combined Company’s compliance with the U.S. federal securities laws and the rules and regulations thereunder.

The Delaware Forum Provision and the Federal Forum Provision may impose additional costs on stockholders of the Combined Company in pursuing any such claims, particularly if the stockholders do not reside in or near the State of Delaware or were permitted to select another jurisdiction. Additionally, the forum selection clauses in the bylaws of the Combined Company may limit its stockholders’ ability to bring a claim in a judicial forum that they find favorable for disputes with the Combined Company or its directors, officers, employees or stockholders, which may discourage such lawsuits against the Combined Company and its directors, officers, employees and stockholders even though an action, if successful, might benefit its stockholders. Alternatively, if a court were to find the Delaware Forum Provision or the Federal Forum Provision contained in the Combined Company’s bylaws to be inapplicable or unenforceable in an action, the Combined Company may incur additional costs associated with resolving such action in other jurisdictions, which could materially and adversely affect its business, financial condition and results of operations.

Provisions that will be in the Combined Company’s certificate of incorporation and bylaws and provisions under Delaware law could make an acquisition of the Combined Company more difficult and may prevent attempts by its stockholders to replace or remove its management.

Provisions that will be included in the Combined Company’s certificate of incorporation and bylaws may discourage, delay or prevent a merger, acquisition or other change in control of the Combined Company that stockholders may consider favorable, including transactions in which its common stockholders might otherwise receive a premium price for their shares. These provisions could also limit the price that investors might be willing to pay in the future for shares of the Combined Company’s common stock, thereby depressing the market price of its common stock. In addition, because the Combined Company’s board of directors will be responsible for appointing the members of the Combined Company’s management team, these provisions may frustrate or prevent any attempts by the Combined Company’s stockholders to replace or remove its current management by making it more difficult for stockholders to replace members of the Combined Company’s board of directors.

Among other things, these provisions will:

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Moreover, because the Combined Company will be incorporated in Delaware, it is governed by the provisions of Section 203 of the DGCL, which prohibits stockholders owning in excess of 15% of the outstanding Combined Company voting stock from merging or combining with the Combined Company. Although VYNE and Yarrow believe these provisions collectively will provide for an opportunity to receive higher bids by requiring potential acquirors to negotiate with the Combined Company’s board of directors, they would apply even if the offer may be considered beneficial by some stockholders. In addition, these provisions may frustrate or prevent any attempts by the Combined Company’s stockholders to replace or remove then current management by making it more difficult for stockholders to replace members of the board of directors, which is responsible for appointing the members of management.

VYNE and Yarrow do not anticipate that the Combined Company will pay any cash dividends in the foreseeable future other than the Cash Dividend that VYNE will declare and pay to the holders of record of outstanding shares of VYNE Common Stock as of a record date prior to the effective time of the Merger, to be set by the VYNE board of directors as close as reasonably practicable to (but not later than) the anticipated Closing Date.

Other than the Cash Dividend, the current expectation is that the Combined Company will retain its future earnings, if any, to fund the growth of the Combined Company’s business as opposed to paying dividends. As a result, capital appreciation, if any, of the Combined Company common stock will be your sole source of gain, if any, for the foreseeable future.

An active trading market for the Combined Company common stock may not develop and its stockholders may not be able to resell their shares of common stock for a profit, if at all.

Prior to the Merger, there had been no public market for shares of Yarrow’s capital stock. An active trading market for the shares of the Combined Company common stock may never develop or be sustained. If an active market for the Combined Company common stock does not develop or is not sustained, it may be difficult for the Combined Company’s stockholders to sell their shares at an attractive price or at all.

Future sales of shares by existing stockholders could cause the Combined Company’s stock price to decline.

If existing securityholders of VYNE and Yarrow sell, or indicate an intention to sell, substantial amounts of the Combined Company common stock in the public market after legal restrictions on resale discussed in this proxy statement/prospectus lapse, the trading price of the Combined Company common stock could decline. Based on shares outstanding as of, 2026, after giving effect to the estimated Exchange Ratio and the shares of Yarrow Common Stock to be issued in the Yarrow Pre-Closing Financing and shares expected to be issued upon completion of the Merger and prior to giving effect to the anticipated VYNE reverse stock split, the Combined Company is expected to have outstanding a total of approximately     shares of common stock immediately following the completion of the Merger (or approximately     shares of common stock after giving effect to the conversion of the exercise of Yarrow Pre-Funded Warrants to be issued in the Yarrow Pre-Closing Financing). Approximately     shares (or approximately     shares, if Yarrow Pre-Funded Warrants are exercised) will be freely tradeable upon completion of the Merger and approximately    shares will become available for sale in the public market beginning 180 days after the Closing as a result of the expiration of lock-up agreements between VYNE on the one hand and certain securityholders of Yarrow on the other hand (and without giving effect to any restrictions

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on resale under securities laws). In addition, shares of common stock that are subject to outstanding options of Yarrow will become eligible for sale in the public market to the extent permitted by the provisions of various vesting agreements and Rules 144 and 701 under the Securities Act. If these shares are sold, the trading price of the Combined Company common stock could decline.

After completion of the Merger, the Combined Company’s executive officers, directors and principal stockholders will have the ability to control or significantly influence all matters submitted to the Combined Company’s stockholders for approval.

Upon the completion of the Merger, and giving effect to the issuance of the shares of Yarrow Common Stock and Yarrow Pre-Funded Warrants prior to the Closing pursuant to the Yarrow Pre-Closing Financing, it is anticipated that the Combined Company’s executive officers, directors and principal stockholders will, in the aggregate, beneficially own approximately% of the outstanding shares of Combined Company common stock (on a fully-diluted basis), subject to beneficial ownership limitations and certain assumptions, including, but not limited to, VYNE’s Net Cash as of Closing being $0. VYNE management currently anticipates VYNE’s Net Cash as of Closing will be approximately $0, after giving effect to the Cash Dividend, which is expected to be approximately $14.5 to $16.5 million in the aggregate, and the currently estimated ownership percentages reflect this projection. As a result, if these stockholders were to choose to act together, they would be able to control or significantly influence all matters submitted to the Combined Company’s stockholders for approval, as well as the Combined Company’s management and affairs. For example, these stockholders, if they choose to act together, would control or significantly influence the election of directors and approval of any merger, consolidation or sale of all or substantially all of the Combined Company’s assets. This concentration of voting power could delay or prevent an acquisition of the Combined Company on terms that other stockholders may desire.

If equity research analysts do not publish research or reports, or publish unfavorable research or reports, about the Combined Company, its business or its market, its stock price and trading volume could decline.

The trading market for the Combined Company common stock will be influenced by the research and reports that equity research analysts publish about it and its business. Equity research analysts may elect to not provide research coverage of the Combined Company common stock after the completion of the Merger, and such lack of research coverage may adversely affect the market price of its common stock. In the event it does have equity research analyst coverage, the Combined Company will not have any control over the analysts or the content and opinions included in their reports. The price of the Combined Company common stock could decline if one or more equity research analysts downgrade its stock or issue other unfavorable commentary or research. If one or more equity research analysts ceases coverage of the Combined Company or fails to publish reports on it regularly, demand for its common stock could decrease, which in turn could cause its stock price or trading volume to decline.

The Combined Company will have broad discretion in the use of the cash and cash equivalents of the Combined Company and the proceeds from the Yarrow Pre-Closing Financing and may invest or spend the proceeds in ways with which you do not agree and in ways that may not increase the value of your investment.

The Combined Company will have broad discretion over the use of the cash and cash equivalents of the Combined Company and the proceeds from the Yarrow Pre-Closing Financing. You may not agree with the Combined Company’s decisions, and its use of the proceeds may not yield any return on your investment. The Combined Company’s failure to apply these resources effectively could compromise its ability to pursue its growth strategy and the Combined Company might not be able to yield a significant return, if any, on its investment of these net proceeds. You will not have the opportunity to influence its decisions on how to use the Combined Company’s cash resources.

The Combined Company’s ability to use NOL carryforwards and other tax attributes may be limited, including as a result of the Merger.

As discussed above, each of VYNE and Yarrow has incurred losses during its history, and the Combined Company does not expect to become profitable in the near future and may never achieve profitability. As of December 31, 2025, VYNE had federal and state NOL carryforwards of approximately $332.1 million and $94.2 million, respectively. VYNE had approximately $7.1 million of federal research and development credits, that may be used to offset future taxable income. VYNE had no state research and development tax credit carryforwards as of December 31, 2025. As of December 31, 2025, Yarrow had federal and state NOL carryforwards of approximately $1.0 million and $1.0 million, respectively. Yarrow had no federal or state research and development tax credit carryforwards as of December 31, 2025. Under current law, U.S. federal NOLs incurred in tax years beginning after December 31, 2017 may be carried forward indefinitely, but the deductibility of such NOL carryforwards is limited to 80% of taxable income. It is uncertain if and to what extent various states will conform to federal law. In addition, under Sections 382 and 383 of the Code, U.S. federal NOL carryforwards and other tax attributes may become subject to an annual limitation in the event of certain

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cumulative changes in ownership. For example, VYNE has completed a 382 study through March 31, 2025, and it noted that VYNE experienced ownership changes in connection with the 2020 merger between Menlo Therapeutics (VYNE’s predecessor company) and Foamix Pharmaceuticals Ltd. and with its private placement transaction in November 2023. As a result of the ownership changes, $40.2 million of federal NOLs are expected to expire unutilized. An “ownership change” pursuant to Section 382 of the Code generally occurs if one or more stockholders or groups of stockholders who own at least 5% of a company’s stock increase their ownership by more than 50 percentage points over their lowest ownership percentage within a rolling three-year period. The Combined Company’s ability to utilize its NOL carryforwards and other tax attributes to offset future taxable income or tax liabilities may be limited as a result of ownership changes, including, as discussed above, in connection with the Merger or other transactions. Similar rules may apply under state tax laws. If the Combined Company earns taxable income, such limitations could result in increased future income tax liability to the Combined Company, and the Combined Company’s future cash flows could be adversely affected.

Changes in tax law could adversely affect the combined company’s business and financial condition.

The Combined Company is subject to federal, state and local income and other taxes in the United States and in foreign jurisdictions because of the scope of its operations. New tax laws, statutes, rules, regulations or ordinances could be enacted at any time. Further, existing tax laws, statutes, rules, regulations or ordinances could be interpreted differently, changed, repealed or modified at any time. Any such enactment, interpretation, change, repeal or modification could adversely affect us, possibly with retroactive effect. For example, the U.S. government recently enacted legislation commonly referred to as the One Big Beautiful Bill Act that (along with prior U.S. federal tax reform legislation) has resulted in significant changes to the taxation of business entities, including, among other changes, the imposition of minimum taxes and excise taxes, changes to the taxation of income derived from international operations, changes in the deduction and amortization of research and development expenditures, and limitations on the deductibility of business interest. Future guidance from the IRS and other taxing authorities with respect to this and other legislation may affect the Combined Company, and certain aspects of such legislation could be repealed or modified in future legislation or sunset in future years. In addition, it is uncertain if and to what extent various states will conform to federal law. To the extent that any such changes in tax laws and regulations have a negative impact on the Combined Company, including as a result of related uncertainty, its business, financial condition, results of operations and cash flows may be materially and adversely impacted.

Unfavorable global economic conditions could adversely affect the Combined Company’s business, financial condition, results of operations or cash flows.

The Combined Company’s results of operations could be adversely affected by general conditions in the global economy and in the global financial markets. A severe or prolonged economic downturn could result in a variety of risks to the Combined Company’s business, including weakened demand for the Combined Company’s product candidates and the Combined Company’s ability to raise additional capital when needed on acceptable terms, if at all. A weak or declining economy could also strain the Combined Company’s suppliers, possibly resulting in supply disruption, or cause the Combined Company’s customers to delay making payments for its services. Any of the foregoing could harm the Combined Company’s business and the Combined Company cannot anticipate all of the ways in which the current economic climate and financial market conditions could adversely impact its business.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This proxy statement/prospectus and the documents incorporated by reference into this proxy statement/ prospectus contain forward-looking statements relating to VYNE, Yarrow, the Merger and the other proposed transactions contemplated thereby.

These forward-looking statements include express or implied statements relating to VYNE’s and Yarrow’s management team’s expectations, hopes, beliefs, intentions or strategies regarding the future. In addition, any statements that refer to projections, forecasts or other characterizations of future events or circumstances, including any underlying assumptions, are forward-looking statements. The words “anticipate,” “believe,” “contemplate,” “continue,” “could,” “estimate,” “expect,” “intends,” “may,” “might,” “plan,” “possible,” “potential,” “predict,” “project,” “should,” “will,” “would” and similar expressions may identify forward-looking statements, but the absence of these words does not mean that a statement is not forward-looking. These forward-looking statements are based on current expectations and beliefs concerning future developments and their potential effects. There can be no assurance that future developments affecting VYNE, Yarrow or the proposed transaction will be those that have been anticipated.

These forward-looking statements involve a number of risks, uncertainties (some of which are beyond VYNE’s or Yarrow’s control) or other assumptions that may cause actual results or performance to be materially different from those expressed or implied by these forward-looking statements. These risks and uncertainties include, but are not limited to: the risk that the conditions to the Closing are not satisfied, including the failure to obtain stockholder approval for the Merger; the risk that the Yarrow Pre-Closing Financing is not completed in a timely manner or at all; uncertainties as to the timing of the consummation of the transaction and the ability of each of VYNE and Yarrow to consummate the transaction, including the Yarrow Pre-Closing Financing; risks related to VYNE’s continued listing on Nasdaq until Closing; risks related to VYNE’s and Yarrow’s ability to correctly estimate their respective operating expenses and expenses associated with the transaction, as well as uncertainties regarding the impact any delay in the Closing would have on the anticipated cash resources of the Combined Company upon Closing and other events and unanticipated spending and costs that could reduce the Combined Company’s cash resources; the occurrence of any event, change or other circumstance or condition that could give rise to the termination of the Merger Agreement; statements regarding the Cash Dividend that VYNE may pay VYNE’s stockholders in connection with the completion of the Merger; the effect of the announcement or pendency of the Merger on VYNE’s or Yarrow’s business relationships, operating results and business generally; costs related to the Merger; the outcome of any legal proceedings that may be instituted against VYNE, Yarrow or any of their respective directors or officers related to the Merger Agreement or the transactions contemplated thereby; the ability of Yarrow to protect its intellectual property rights; competitive responses to the transaction; unexpected costs, charges or expenses resulting from the transaction; potential adverse reactions or changes to business relationships resulting from the announcement or completion of the transaction; adverse legislative, regulatory, political and economic developments; the risk of setbacks in Yarrow’s plans to develop and commercialize product candidates for the treatment of autoimmune diseases; Yarrow’s ability to maintain the GenSci License Agreement and enter into new license and collaboration agreements; delays or challenges in Yarrow’s ongoing and future preclinical studies and clinical trials and the reporting of data from those studies and trials; the risk that the efficacy and safety of Yarrow’s product candidates will be disappointing compared with expectations; Yarrow’s plans relating to the further development of its programs, including additional indications Yarrow may pursue; the risk that the size of the market opportunity for Yarrow’s programs, including Yarrow’s estimates of the number of patients who suffer from the diseases it is targeting may be lower than expected; Yarrow’s reliance on third parties to conduct additional preclinical studies and clinical trials of its programs and for the manufacture of Yarrow’s programs for preclinical studies and clinical trials; the risk of negative developments in the cost, timing and results of Yarrow’s preclinical and clinical development activities and planned clinical trials; Yarrow’s plans regarding, and its ability to maintain, obtain, and negotiate favorable terms of, any collaboration, licensing or other arrangements that may be necessary or desirable to develop, manufacture or commercialize its programs; and the timing of and Yarrow’s ability to obtain and maintain regulatory approvals for its product candidates, as well as future product candidates.

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Should one or more of these risks or uncertainties materialize, or should any of VYNE’s or Yarrow’s assumptions prove incorrect, actual results may vary in material respects from those projected in these forward-looking statements. There may be additional risks that VYNE considers immaterial or which are unknown. It is not possible to predict or identify all such risks. VYNE’s and Yarrow’s forward-looking statements only speak as of the date they are made, and VYNE and Yarrow do not undertake any obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as may be required under applicable securities laws.

For a discussion of the factors that may cause VYNE, Yarrow or the Combined Company’s actual results, performance or achievements to differ materially from any future results, performance or achievements expressed or implied in such forward-looking statements, or for a discussion of risk associated with the ability of VYNE and Yarrow to complete the Merger and the effect of the Merger on the business of VYNE, Yarrow and the Combined Company, please see the section titled “Risk Factors” beginning on page 27 of this proxy statement/prospectus. Additional factors that could cause actual results to differ materially from those expressed in the forward-looking statements are discussed in reports filed with the SEC by VYNE and incorporated by reference herein. Please see the section titled “Where You Can Find More Information” beginning on page 347 of this proxy statement/prospectus. There can be no assurance that the Merger will be completed, or if it is completed, that it will be completed within the anticipated time period or that the expected benefits of the Merger will be realized.

If any of these risks or uncertainties materialize or any of these assumptions prove incorrect, the results of VYNE, Yarrow or the Combined Company could differ materially from the forward-looking statements. All forward-looking statements in this proxy statement/prospectus are current only as of the date on which the statements were made. VYNE and Yarrow do not undertake any obligation to (and expressly disclaim any such obligation to) publicly update any forward-looking statement to reflect events or circumstances after the date on which any statement is made or to reflect the occurrence of unanticipated events.

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THE SPECIAL MEETING IN LIEU OF ANNUAL MEETING OF VYNE STOCKHOLDERS

Date, Time and Place

The VYNE Special Meeting will be held on         , 2026, commencing at      Eastern Time, unless postponed or adjourned to a later date. The VYNE Special Meeting will be held at. You will be able to attend and participate in the VYNE Special Meeting in person where you will be able to ask questions and vote. VYNE is sending this proxy statement/prospectus to its stockholders in connection with the solicitation of proxies by the VYNE board of directors for use at the VYNE Special Meeting and any adjournments or postponements of the VYNE Special Meeting. This proxy statement/prospectus is first being furnished to VYNE stockholders on or about         , 2026.

Purpose of the VYNE Special Meeting

The purposes of the VYNE Special Meeting are:

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Each of Proposal Nos. 1 and 2 is a condition to completion of the Merger. The issuance of VYNE Common Stock, including shares of VYNE Common Stock issuable upon exercise of VYNE Pre-Funded Warrants issued in exchange for Yarrow Pre-Funded Warrants sold in the Yarrow Pre-Closing Financing, and the change of control of VYNE resulting from the Merger will not take place unless Proposal Nos. 1 and 2 are approved by VYNE stockholders and the Merger is consummated. The amendment to the VYNE Charter to increase the number of authorized shares of VYNE Common Stock will not take place unless Proposal Nos. 1, 2, and 3 are approved by VYNE stockholders and the Merger is consummated. However, the VYNE board of directors may determine to effect the reverse stock split if approved by VYNE stockholders following the special meeting, even if Proposal No. 1 is not approved, or the Merger is not otherwise completed.

Recommendation of the VYNE Board of Directors

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Record Date and Voting Power

Only holders of record of VYNE Common Stock at the close of business on the Record Date of         , 2026, are entitled to notice of, and to vote at, the VYNE Special Meeting. At the close of business on           , 2026, there were       registered holders of record of VYNE Common Stock and there were          shares of VYNE Common Stock issued and outstanding. Each share of VYNE Common Stock entitles the holder thereof to one vote on each matter submitted for stockholder approval.

Voting and Revocation of Proxies

The proxy accompanying this proxy statement/prospectus is solicited on behalf of the VYNE board of directors for use at the VYNE Special Meeting.

If, as of the Record Date referred to above, your shares were registered directly in your name with the transfer agent for VYNE Common Stock, Equiniti Trust Company, LLC, then you are a stockholder of record. As a stockholder of record, you may vote at the VYNE Special Meeting or vote by proxy. Whether or not you plan to attend the VYNE Special Meeting, VYNE urges you to vote by proxy over the telephone or on the internet as instructed below or return the proxy card VYNE may mail to you to ensure your vote is counted, the form of which is attached hereto as Annex E.

The procedures for voting are as follows:

If you are a stockholder of record, you may vote at the VYNE Special Meeting. Alternatively, you may vote by proxy by using the accompanying proxy card, over the internet or by telephone. Whether or not you plan to attend the VYNE Special Meeting, VYNE encourages you to vote by proxy to ensure your vote is counted. Even if you have submitted a proxy before the VYNE Special Meeting, you may still attend the VYNE Special Meeting and vote. In such case, your previously submitted proxy will be disregarded.

If you are a beneficial owner of shares registered in the name of your broker, bank or other agent, you should have received a voting instruction card and voting instructions with these proxy materials from that organization rather than from VYNE. Simply

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complete and mail the voting instruction card to ensure that your vote is counted. To vote at the VYNE Special Meeting, you must obtain a valid proxy from your broker, bank or other agent. Follow the instructions from your broker, bank or other agent included with these proxy materials, or contact your broker, bank or other agent to request a proxy form.

VYNE provides internet proxy voting to allow you to vote your shares online, with procedures designed to ensure the authenticity and correctness of your proxy vote instructions. However, please be aware that you must bear any costs associated with your internet access, such as usage charges from internet access providers and telephone companies.

If you are a beneficial owner of shares held in street name and you do not instruct your broker, bank or other agent how to vote your shares, your broker, bank or other agent will only be able to vote your shares with respect to proposals considered to be “routine.” Your broker, bank or other agent is not entitled to vote your shares with respect to “non-routine” proposals. As a result, VYNE urges you to direct your broker, bank or other agent how to vote your shares on all proposals to ensure that your vote is counted.

Broker non-votes, if any, will be treated as shares present for the purpose of determining the presence of a quorum for the transaction of business at the VYNE Special Meeting. Broker non-votes, if any, will not be counted as “votes properly cast” or “shares entitled to vote” and will therefore have no effect on Proposal Nos. 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10.

All properly executed proxies that are not revoked will be voted at the VYNE Special Meeting and at any adjournments or postponements of the VYNE Special Meeting in accordance with the instructions contained in the proxy. If a stockholder of record of VYNE Common Stock executes and returns a proxy and does not specify otherwise, the shares represented by that proxy will be voted “FOR” all of the proposals in accordance with the recommendation of the VYNE board of directors.

Required Vote

The presence, in person or being represented by proxy, at the VYNE Special Meeting of the holders of at least one-third of the shares of VYNE Common Stock outstanding and entitled to vote at the VYNE Special Meeting is necessary to constitute a quorum at the meeting for the purpose of approving the proposals. Abstentions or “WITHHOLD” votes and broker non-votes will be counted towards the presence of a quorum. The affirmative vote of a majority of the votes properly cast for and against by the holders of VYNE Common Stock at the VYNE Special Meeting, assuming a quorum is present, is required for approval of Proposal Nos. 1, 2, 3, 4, 5, 7, 8, 9 and 10. The affirmative vote of a plurality of the votes properly cast by the holders of VYNE Common Stock entitled to vote at the VYNE Special Meeting, assuming a quorum is present, is required for the election of the director nominated via Proposal No. 6.

Each of Proposal No. 1 and Proposal No. 2 is a condition to completion of the Merger. The closing of the Yarrow Pre-Closing Financing is conditioned upon the satisfaction or waiver of each of the conditions to the closing of the Merger as well as certain other conditions. Therefore, the Merger and the Yarrow Pre-Closing Financing cannot be consummated without the approval of Proposal Nos. 1 and 2. The issuance of VYNE Common Stock in connection with the Merger and the change of control of VYNE resulting from the Merger will not take place unless Proposal Nos. 1 and 2 are approved by VYNE stockholders and the reverse stock split is effected and the Merger is consummated. The amendment to the VYNE Charter to effect a reverse stock split of VYNE issued and outstanding common stock will not take place unless Proposal No. 2 is approved by the requisite VYNE stockholders. VYNE may still elect to proceed with the reverse stock split if Proposal No. 2 is approved by VYNE’s stockholders even if Proposal No. 1 is not approved, or even if approved, the Merger is not consummated. Additionally, Proposal Nos. 3, 4, 5 and 8 are each conditioned on the consummation of the Merger. Therefore, if Proposal No. 1 and Proposal No. 2 are not approved and the Merger is not consummated, Proposal Nos. 3, 4, 5 and 8 will each have no effect, even if approved by VYNE stockholders.

Votes will be counted by the inspector of election appointed for the meeting, who will separately count “FOR” and “AGAINST” votes, abstentions or “WITHHOLD” votes (as applicable), and broker non-votes. Abstentions or “WITHHOLD” votes and broker non-votes will be treated as shares present for the purpose of determining the presence of a quorum for the transaction of business at the VYNE Special Meeting, but will not be counted as votes cast and will have no effect on the outcome of the vote for each proposal.

As described in the accompanying proxy statement/prospectus, certain VYNE stockholders who in the aggregate beneficially owned approximately 3.0% of the outstanding shares of VYNE Common Stock as of December 17, 2025, and RTW Investments, OrbiMed, Janus Henderson Investors, venBio Partners, Logos Capital and LifeSci Venture Partners, as Yarrow stockholders who in the aggregate owned approximately 95.9% of the outstanding shares of Yarrow capital stock as of December 17, 2025, are parties to stockholder support agreements with VYNE and Yarrow whereby such stockholders have agreed to vote in favor of the approval of

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the transactions contemplated therein, including, with respect to such Yarrow stockholders, adoption of the Merger Agreement and approval of the Merger and, with respect to such VYNE stockholders, Proposal Nos. 1 and 2, subject to the terms of the support agreements. Following the effectiveness of the registration statement on Form S-4 of which the accompanying proxy statement/prospectus is a part and pursuant to the Merger Agreement, Yarrow stockholders holding a sufficient number of shares of Yarrow Capital Stock to adopt the Merger Agreement and approve the Merger and related transactions will be asked to execute written consents providing for such adoption and approval.

Solicitation of Proxies

In addition to solicitation by mail, the directors, officers, employees and agents of VYNE may solicit proxies from VYNE stockholders by personal interview, telephone, email, fax or otherwise. VYNE and Yarrow will share equally the costs of printing and filing this proxy statement/prospectus and proxy card. Arrangements will also be made with brokerage firms and other custodians, nominees and fiduciaries who are record holders of VYNE Common Stock for the forwarding of solicitation materials to the beneficial owners of VYNE Common Stock. VYNE will reimburse these brokers, custodians, nominees and fiduciaries for the reasonable out of pocket expenses they incur in connection with the forwarding of solicitation materials. VYNE has retained D.F. King & Co., Inc. as its proxy solicitor.

VYNE will pay the fees of the Proxy Solicitor, which VYNE expects to be approximately $11,000, plus reimbursement for certain out-of-pocket expenses. VYNE has agreed to indemnify the Proxy Solicitor and related parties against certain liabilities and expenses arising out of its services in connection with the special meeting.

Other Matters

As of the date of this proxy statement/prospectus, the VYNE board of directors does not know of any business to be presented at the VYNE Special Meeting other than as set forth in the notice accompanying this proxy statement/prospectus. If any other matters should properly come before the VYNE Special Meeting, it is intended that the shares represented by proxies will be voted with respect to such matters in accordance with the judgment of the persons voting the proxies.

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THE MERGER

This section and the section titled “The Merger Agreement” beginning on page 160 of this proxy statement/ prospectus describe the material aspects of the Merger and the Merger Agreement. While VYNE and Yarrow believe that this description covers the material terms of the Merger and the Merger Agreement, it may not contain all of the information that is important to you. You should read carefully this entire proxy statement/ prospectus for a more complete understanding of the Merger and the Merger Agreement and the other documents to which you are referred in this proxy statement/prospectus. Please see the section titled “Where You Can Find More Information” beginning on page 347 of this proxy statement/prospectus.

Background of the Transaction

The following chronology summarizes the key meetings and events that led to the signing of the Merger Agreement. The following chronology does not purport to catalogue every conversation among the VYNE board of directors or committees thereof or the representatives of VYNE and other parties.

Background of the Merger

The following chronology is a summary description of the background of the negotiations and the proposed Merger and does not purport to catalogue every conversation among representatives of VYNE, Yarrow and other parties. In addition to formal VYNE board meetings, VYNE management had informal discussions with the VYNE board of directors throughout the process. The terms of the Merger Agreement are the result of extensive arm’s-length negotiations among Yarrow management and VYNE management and members of the VYNE board of directors and the Yarrow board of directors, along with VYNE’s financial advisor and VYNE’s and Yarrow’s respective legal counsels.

Prior to the commencement of its alternative strategic assessment process in August 2025 (discussed below), VYNE was focused on researching and developing products containing small molecule bromodomain and extra-terminal domain (“BET”) inhibitors for immune-mediated diseases. Until July 2025, VYNE’s lead product candidate was repibresib gel (also known as VYN201), a topically administered, small molecule pan-BD BET inhibitor. In July 2025, VYNE announced that its Phase 2b trial for repibresib gel in nonsegmental vitiligo did not meet its primary efficacy endpoint and subsequently terminated the trial. VYNE is also developing VYN202, an orally administered, small molecule BD2-selective BET inhibitor, which was in a Phase 1b trial for psoriasis until April 2025, when the FDA placed a clinical hold on the trial following an observation of testicular toxicity in dogs from a non-clinical toxicology study of VYN202. The FDA partially lifted the hold in certain doses for females, but VYNE made the decision to unblind the clinical data from the seven subjects who were enrolled in the trial. Based on the interim unblinded data together with promising results from multiple pre-clinical models, VYNE terminated the Phase 1b psoriasis trial in support of continued advancement of VYN202 into other serious, immune mediated diseases with more limited effective treatment options. In October 2025, VYNE initiated a repeat 12-week non-clinical toxicology study in male dogs to potentially maximize strategic optionality. The study is expected to be completed in the second half of 2026, with a final report expected in the fourth quarter of 2026.