UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No. )

Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐

Check the appropriate box:

Karyopharm Therapeutics Inc.

(Name of Registrant as Specified in its Charter)

(Name of Person(s) Filing Proxy Statement, if Other Than the Registrant)

Payment of Filing Fee (Check all boxes that apply):

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS TO BE HELD ON MAY 21, 2026

Dear Stockholder:

You are cordially invited to attend our 2026 Annual Meeting of Stockholders (the “Annual Meeting”) to be held on May 21, 2026, beginning at 9:00 a.m. Eastern Time, exclusively online via the Internet as a virtual web conference at www.virtualshareholdermeeting.com/KPTI2026 to consider and act upon the following matters:

Our Annual Meeting will be a “virtual meeting” of stockholders, which will be conducted exclusively online via the Internet as a virtual web conference. There will not be a physical meeting location, and stockholders will not be able to attend the Annual Meeting in person. This means that you can attend the Annual Meeting online, vote your shares during the online meeting and submit questions during the online meeting by visiting the above-mentioned Internet site. We believe that hosting a virtual meeting will enable greater stockholder attendance and participation from any location around the world. We will continue to evaluate the format of our stockholder meetings on an annual basis.

A printed copy of our proxy materials, including a proxy card, is being mailed to our stockholders on or about the date hereof.

Only stockholders of record at the close of business on March 30, 2026, the record date for the Annual Meeting, are entitled to notice of, and will be entitled to vote at, the Annual Meeting, or any adjournments or postponements thereof.

If you are a stockholder of record, you may vote or submit a proxy in one of the following ways:

If your shares are held in “street name,” meaning that they are held for your account by a broker or other nominee, you will receive instructions from the holder of record that you must follow to vote your shares.

Your vote is important to us. Whether or not you plan to attend the Annual Meeting online, we urge you to take the time to submit a proxy to vote your shares. Further information about how to attend the Annual Meeting online, vote your shares online during the Annual Meeting and submit your questions online during the Annual Meeting is included in the accompanying proxy statement.

By Order of the Board of Directors,

Richard Paulson

President, Chief Executive Officer and Director

Newton, Massachusetts

April 13, 2026

WHETHER OR NOT YOU PLAN TO ATTEND THE ANNUAL MEETING ONLINE, WE URGE YOU TO SUBMIT A PROXY TO VOTE YOUR SHARES BY SUBMITTING YOUR PROXY OVER THE INTERNET OR BY TELEPHONE, OR BY COMPLETING, DATING, SIGNING AND RETURNING THE ENCLOSED PROXY CARD IN THE ACCOMPANYING ENVELOPE. NO POSTAGE NEED BE AFFIXED IF THE PROXY CARD IS MAILED IN THE UNITED STATES.

TABLE OF CONTENTS

PROXY STATEMENT FOR THE 2026 ANNUAL MEETING OF STOCKHOLDERS TO BE HELD ON Thursday, MAY 21, 2026

The Board of Directors (the “Board”) of Karyopharm Therapeutics Inc. (which we also refer to as “Karyopharm,” the “Company,” “we,” “us,” or “our”) is soliciting proxies for use at the 2026 Annual Meeting of Stockholders (the “Annual Meeting”), to be held exclusively online via the Internet as a virtual web conference at www.virtualshareholdermeeting.com/KPTI2026 on Thursday, May 21, 2026 at 9:00 a.m. Eastern Time. We have determined that the Annual Meeting will be held in a virtual meeting format only, via the Internet, with no physical in-person meeting. At our virtual Annual Meeting, stockholders will be able to attend, vote and submit questions by visiting www.virtualshareholdermeeting.com/KPTI2026. Further information about how to attend the Annual Meeting online, vote your shares online during the Annual Meeting and submit questions during the Annual Meeting is included in this proxy statement.

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting of

Stockholders to be Held on Thursday, May 21, 2026:

This proxy statement and our annual report are available electronically at www.proxyvote.com.

A printed copy of our proxy materials, including proxy card, is being mailed to our stockholders on April 13, 2026.

GENERAL INFORMATION ABOUT THIS PROXY STATEMENT, THE ANNUAL MEETING AND VOTING

How do I attend the virtual Annual Meeting?

This year’s Annual Meeting will be conducted as a virtual meeting of stockholders. We will host the Annual Meeting exclusively online via the Internet as a virtual web conference. You will be able to attend the Annual Meeting online, vote your shares online during the Annual Meeting and submit your questions online during the Annual Meeting by visiting www.virtualshareholdermeeting.com/KPTI2026. There will not be a physical meeting location, and you will not be able to attend the Annual Meeting in person. The webcast will start at 9:00 a.m. Eastern Time on Thursday, May 21, 2026. You will need the control number included on your proxy card or in the instructions from your broker in order to be able to attend the Annual Meeting online. Information contained on this website is not incorporated by reference into this proxy statement or any other report we file with the Securities and Exchange Commission (the “SEC”).

Online check-in will begin at 8:45 a.m. Eastern Time on Thursday, May 21, 2026, and you should allow ample time for the online check-in proceedings. If you encounter any difficulties accessing the virtual Annual Meeting during the check-in or meeting time, please call the technical support number that will be posted on the virtual Annual Meeting log-in page. Technical support will be available starting at 8:45 a.m. on the day of the meeting.

Why is the Annual Meeting a virtual, online meeting?

We believe that hosting a virtual meeting will facilitate stockholder attendance and participation at the Annual Meeting by enabling stockholders to participate remotely from any location around the world. Our virtual meeting will be governed by our Rules of Conduct and Procedures, which will be posted on the virtual meeting platform on the date of the Annual Meeting. We have designed the virtual Annual Meeting to provide the same rights and opportunities to participate as stockholders would have at an in-person meeting, including the right to vote and ask questions through the virtual meeting platform. There will not be a physical meeting location, and stockholders will not be able to attend the Annual Meeting in person. We will continue to evaluate the format of our stockholder meetings on an annual basis.

Why did you send me these proxy materials?

We are providing these proxy materials because our Board is soliciting your proxy to vote at the Annual Meeting. This proxy statement summarizes information related to your vote at the Annual Meeting. All stockholders who find it convenient to do so are cordially invited to attend the Annual Meeting online. However, you do not need to attend the meeting virtually to vote your shares. Instead, you may submit a proxy to vote your shares as described in further detail in the answer to the question “How do I vote?” below.

Who can vote at the Annual Meeting and what are the voting rights of such stockholders?

Only stockholders of record at the close of business on March 30, 2026 (the “Record Date”) are entitled to vote at the Annual Meeting. On the Record Date, there were 22,543,316 shares of our common stock outstanding and entitled to vote (each share entitles its holder to one vote). Common stock is our only class of stock outstanding.

May I see a list of stockholders entitled to vote as of the Record Date?

A list of registered stockholders as of the close of business on the Record Date will be available for examination by any stockholder for any purpose germane to the Annual Meeting for a period of ten (10) days ending on the day before the Annual Meeting. If you wish to view this list, please contact our Corporate Secretary at Karyopharm Therapeutics Inc., 85 Wells Avenue, Newton, Massachusetts 02459, Attention: Corporate Secretary, (617) 658-0600.

What is the purpose of the Annual Meeting?

At the Annual Meeting, stockholders will consider and vote on the following matters:

How many votes do I have?

Each stockholder is entitled to one vote for each share of our common stock held by such stockholder on the Record Date.

How do I vote?

If you are the “record holder” of your shares, meaning that you own your shares in your own name and not through a bank, brokerage firm or other nominee (each a “Nominee”), you may submit a proxy or vote your shares by any of the following methods:

If your shares are held in “street name,” meaning they are held for your account by a Nominee, you may submit voting instructions or vote your shares by any of the following methods:

If you hold your shares of our common stock in multiple accounts, you should vote your shares or submit a proxy as described above for each account.

Can I revoke or change my vote?

If your shares are registered directly in your name, you may revoke your proxy and change your vote at any time before the Annual Meeting. To do so, you must do one of the following:

If your shares are held in “street name,” you may submit new voting instructions with a later date by contacting your Nominee. You may also vote your shares online while virtually attending the Annual Meeting, which will have the effect of revoking any previously submitted voting instructions.

Will my shares be voted if I do not return my proxy or do not provide specific voting instructions on the proxy card or voting instruction form that I submit?

If your shares are registered directly in your name, your shares will not be voted if you do not submit a proxy over the Internet, by telephone or by returning your proxy by mail prior to the Annual Meeting, or attend and vote online at the virtual Annual Meeting. If you submit a proxy card without giving specific voting instructions on one or more matters listed on your proxy card, your shares will be voted as recommended by our Board on such matters, and as the proxyholders may determine in their discretion how to vote with respect to the matters properly presented for a vote at the Annual Meeting.

If your shares are held in “street name,” your Nominee may, under certain circumstances, vote your shares if you do not timely return your voting instructions. Stock exchange rules permit a broker to vote shares held in a brokerage account on certain proposals if the broker does not receive voting instructions from you. Stock exchange rules, however, prohibit brokers from voting uninstructed shares in the case of election of directors, executive compensation matters and certain other matters. Of the matters to be voted on at the Annual Meeting, we expect the only proposal on which brokers will have discretionary voting authority is the ratification of the appointment of our independent registered public accounting firm (Proposal 5).

A “broker non-vote” on a matter results when your broker returns a proxy but does not vote on a particular proposal because it does not have discretionary authority to vote on that proposal and has not received voting instructions from you.

We encourage you to timely provide voting instructions to your Nominee. This ensures that your shares will be voted at the Annual Meeting according to your instructions. You should receive directions from your Nominee about how to submit your voting instructions to them.

What constitutes a quorum at the Annual Meeting?

A quorum is needed to hold a valid meeting. A quorum will be present if the holders of at least a majority in voting power of the shares of common stock issued and outstanding and entitled to vote on the Record Date are present at the virtual Annual Meeting either “in person” virtually or as represented by proxy. For purposes of establishing a quorum, abstentions and broker non-votes are counted as present or represented. If a quorum is not present, we expect to adjourn the Annual Meeting until we obtain a quorum. The presence at the Annual Meeting, in person or by proxy, of holders representing a majority in voting power of our outstanding common stock as of the Record Date, or 11,271,659 shares, constitutes a quorum at the Annual Meeting, permitting us to conduct the business of the Annual Meeting. Shares present virtually during the Annual Meeting will be considered shares of common stock present “in person” at the meeting.

What vote is required to approve each matter and how are votes counted?

Proposal 1 - Election of Directors

The two nominees for director to receive the highest number of votes FOR election will be elected as Class I directors. This is called a plurality. Shares held in street name by Nominees who indicate on their proxies that they do not have authority to vote the shares on Proposal 1 will not be counted as votes FOR or WITHHELD from any director nominee and will be treated as broker non-votes. Broker non-votes will have no effect on the voting on Proposal 1.

You may:

Votes that are withheld will not be included in the vote tally for the election of directors and will not affect the vote results.

Proposal 2 - Approval of an Amendment to our 2022 Plan to Increase the Number of Shares of our Common Stock Available for Issuance Thereunder by 3,000,000 Shares

To approve Proposal 2, stockholders holding a majority of the votes cast on the matter must vote FOR the proposal. Shares held in street name by Nominees who indicate on their proxies that they do not have authority to vote the shares on Proposal 2 will not be counted as votes FOR or AGAINST Proposal 2 and will be treated as broker non-votes. Broker non-votes will have no effect on the voting on Proposal 2. If you vote to ABSTAIN on Proposal 2, your shares will not be voted FOR or AGAINST the proposal and will also not be counted as votes cast or shares voting on Proposal 2. As a result, voting to ABSTAIN will have no effect on the voting on Proposal 2.

Proposal 3 - Approval of an Amendment to our Amended & Restated ESPP to Increase the Number of Shares of our Common Stock Available for Issuance Thereunder by 1,400,000 Shares

To approve Proposal 3, stockholders holding a majority of the votes cast on the matter must vote FOR the proposal. Shares held in street name by Nominees who indicate on their proxies that they do not have authority to vote the shares on Proposal 3 will not be counted as votes FOR or AGAINST Proposal 3 and will be treated as broker non-votes. Broker non-votes will have no effect on the voting on Proposal 3. If you vote to ABSTAIN on Proposal 3, your shares will not be voted FOR or AGAINST the proposal and will also not be counted as votes cast or shares voting on Proposal 3. As a result, voting to ABSTAIN will have no effect on the voting on Proposal 3.

Proposal 4 - Advisory Vote on the Compensation of Our Named Executive Officers

To approve Proposal 4, stockholders holding a majority of the votes cast on the matter must vote FOR the approval of the compensation of our NEOs, as described in this proxy statement. Shares held in street name by Nominees who indicate on their proxies that they do not have authority to vote the shares on Proposal 4 will not be counted as votes FOR or AGAINST Proposal 4 and will be treated as broker non-votes. Broker non-votes will have no effect on the voting on Proposal 4. If you vote to ABSTAIN on Proposal 4, your shares will not be voted FOR or AGAINST the proposal and will also not be counted as votes cast or shares voting on Proposal 4. As a result, voting to ABSTAIN will have no effect on the voting on Proposal 4. As an advisory vote, this proposal is not binding. The outcome of this advisory vote will not overrule any decision by us or our Board (or any committee thereof). However, our Compensation Committee and our Board value the opinions expressed by our stockholders in their vote on this proposal and will consider the outcome of the vote when making future compensation decisions for our NEOs.

Proposal 5 - Ratification of the Appointment of our Independent Registered Public Accounting Firm

To approve Proposal 5, stockholders holding a majority of the votes cast on the matter must vote FOR the proposal. If your shares are held by your Nominee in “street name” and you do not timely provide voting instructions with respect to your shares, we expect that your Nominee will have the authority to vote your shares on Proposal 5. If you vote to ABSTAIN on Proposal 5, your shares will not be voted FOR or AGAINST the proposal and will also not be counted as votes cast or shares voting on Proposal 5. As a result, voting to ABSTAIN will have no effect on the voting on Proposal 5. Although stockholder ratification of our Audit Committee’s appointment of Ernst & Young LLP as our independent registered public accounting firm for the year ending December 31, 2026 is not required, we believe that it is advisable to give stockholders an opportunity to ratify this appointment. If this proposal is not approved at the Annual Meeting, our Audit Committee and Board will reconsider the appointment of Ernst & Young LLP as our independent registered public accounting firm for future service.

How does the Board recommend that I vote on the proposals?

Our Board recommends that you vote:

Are there other matters to be voted on at the Annual Meeting?

We do not know of any matters that may come before the Annual Meeting other than Proposals 1, 2, 3, 4, and 5. If any other matters are properly presented at the Annual Meeting, the persons named in the accompanying proxy intend to vote, or otherwise act, in accordance with their judgment on the matter.

How do I submit a question at the virtual Annual Meeting?

We invite appropriate questions pertinent to the Company and the matters to be voted on at the Annual Meeting. We will not be providing a business update at the Annual Meeting or discussing matters related to our business or operations. If there are any matters of individual concern to a stockholder or not related to the matters to be voted on at the Annual Meeting, or if a question was not otherwise answered, such matters may be raised separately after the Annual Meeting by contacting Investor Relations at https://investors.karyopharm.com/contact-us.

If you wish to submit a question on the day of the Annual Meeting, beginning at 8:45 a.m. Eastern Time, you may log into the virtual meeting platform at www.virtualshareholdermeeting.com/KPTI2026, proceed to the “Ask A Question” area on the lower left side of the screen, select a “Question Topic” from the drop down menu, type your question where it states “Enter Question” and click the “Submit” tab. Our virtual meeting will be governed by our Rules of Conduct and Procedures, which will be posted at www.virtualshareholdermeeting.com/KPTI2026 during the Annual Meeting. The Rules of Conduct and Procedures will address the ability of stockholders to ask questions during the meeting, including rules on permissible topics, and rules for how questions and comments will be recognized. We will answer appropriate questions that are pertinent to the Company and the matters to be voted on by the stockholders at the Annual Meeting. Because time is limited at the Annual Meeting, we may not be able to answer all questions that are submitted. To promote fairness, efficiently use the Company’s resources and address all stockholder questions, we will limit each stockholder to one question, which should be succinct and should cover only one topic. Questions from multiple stockholders on the same topic or that are otherwise related may be grouped, summarized and answered together.

How are we soliciting proxies and tabulating votes?

We will pay all of the costs of soliciting proxies. In addition to these proxy materials, our directors, officers, and other employees may also solicit proxies in person or by mail, telephone, fax or email without additional compensation. We have retained Alliance Advisors, LLC, a proxy solicitation firm, to assist in the solicitation of proxies for a fee of approximately $15,000 plus expenses. We will also reimburse brokerage firms, banks and other agents for the cost of forwarding proxy materials to beneficial owners. Votes will be tabulated by Broadridge. If you have any questions or need assistance with voting please contact Alliance Advisors.

Alliance Advisors

150 Clove Road

Suite 400

Little Falls, NJ 07424

KPTI@AllianceAdvisors.com

How do I obtain an Annual Report on Form 10-K?

All of our SEC filings are available free of charge under the heading “Financial Information – SEC Filings” in the

“Investors” section of our website at www.karyopharm.com.

If you would like a physical copy of our Annual Report on Form 10-K for the year ended December 31, 2025, which we filed with the SEC on February 13, 2026 (the “2025 Annual Report”), we will send you one without charge. Please write to:

Karyopharm Therapeutics Inc.

85 Wells Avenue

Newton, Massachusetts 02459

Attn: Investor Relations

How can I find out the results of the voting at the virtual Annual Meeting?

Preliminary voting results will be announced at the Annual Meeting. Final voting results will be published in a current report on Form 8-K that we expect to file with the SEC within four business days after the Annual Meeting. If final voting results are not available to us in time to file a Form 8-K within four business days after the Annual Meeting, we intend to file a Form 8-K to publish preliminary results and, within four business days after the final results are known to us, file an amended Form 8-K to publish the final results.

PROPOSAL 1:

ELECTION OF DIRECTORS

Our Board is divided into three classes, with one class of our directors standing for election each year to serve for a three-year term. Directors for each class are elected at the annual meeting of stockholders held in the year in which the term for their class expires and hold office until their resignation or removal or until their successors are duly elected and qualified. In accordance with our certificate of incorporation and bylaws, our Board may fill existing vacancies on the Board by appointment.

The term of office of our Class I directors, Barry E. Greene and Christy J. Oliger, will expire at the Annual Meeting. Accordingly, the nominees for Class I director for election at the Annual Meeting are Mr. Greene and Ms. Oliger. If Mr. Greene and Ms. Oliger are elected at the Annual Meeting, each such individual will be elected to serve for a three-year term that will expire at our 2029 annual meeting of stockholders and until such individual’s successor is duly elected and qualified.

If no contrary indication is made, proxies are to be voted for Mr. Greene and Ms. Oliger, or in the event that either of Mr. Greene and Ms. Oliger is not a candidate or is unable to serve as a director at the time of the election (which is not currently expected), for any nominee who is designated by our Board to fill the vacancy.

Our Board currently consists of seven members. In identifying and selecting our directors, our Corporate Governance Guidelines provide that the background and qualifications of the members of our Board considered as a group should provide a significant breadth of experience, knowledge, and ability to assist our Board in fulfilling its responsibilities. Our priority in the selection of board members is: (a) identification of members who will further the interests of our stockholders through his or her established record of professional accomplishment; (b) ability to contribute positively to the collaborative culture among board members; (c) knowledge of our business; (d) understanding of the competitive landscape; and (e) adherence to high ethical standards. Our Board believes that diversity, including a variety of experiences, perspectives and skills, is an added benefit to the Board and its ability to function effectively. Therefore, to the extent consistent with applicable legal requirements and the Board’s fiduciary duties, the Board will consider such diversity among the factors it considers when evaluating potential candidates. Certain individual qualifications and skills of our directors that contribute to our Board’s effectiveness as a whole are summarized and described below.

Information Regarding Directors

The information set forth below as to the directors and nominees for directors has been furnished to us by the directors and nominees for directors:

Nominees for Election to the Board of Directors

For a Three-Year Term Expiring at the

2029 Annual Meeting of Stockholders (Class I)

Barry E. Greene. Mr. Greene has served as a member of our Board since 2013 and as our Lead Independent Director since 2015. Mr. Greene served as Chief Executive Officer of Sage Therapeutics, Inc. (“Sage”), a public biopharmaceutical company, from 2020 to August 2025. Mr. Greene served as President of Alnylam Pharmaceuticals, Inc. (“Alnylam”), a public biopharmaceutical company, from 2007 to 2020, and as its Chief Operating Officer from 2003 to 2016. Prior to Alnylam, he was General Manager of Oncology at Millennium Pharmaceuticals, Inc. (“Millennium”), a public biopharmaceutical company. Prior to joining Millennium in 2001, Mr. Greene served as Executive Vice President and Chief Business Officer for Mediconsult.com. Prior to Mediconsult.com, Mr. Greene’s experience included serving as Vice President of Marketing and Customer Services for AstraZeneca (formerly AstraMerck), a public biopharmaceutical company; Vice President, Strategic Integration with responsibility for the AstraZeneca North American post-merger integration; and a partner of Andersen Consulting. Mr. Greene served as a member of the board of directors of Sage from 2020 to August 2025. Mr. Greene served as a member of the board of directors of BCLS Acquisition Corp., a special purpose acquisition company, from 2020 to October 2022. From 2007 to August 2021, Mr. Greene served as a member of

the board of directors of Acorda Therapeutics, Inc., a public biopharmaceutical company, where he also served as a member of its compensation committee. Mr. Greene received his B.S. in Industrial Engineering from the University of Pittsburgh and served as a Senior Scholar at Duke University’s Medical School and Fuqua School of Business. We believe Mr. Greene’s qualifications to serve on our Board and as our Lead Independent Director include his extensive experience in the healthcare and consulting industries as well as his practical experience with business and product aspects of the biopharmaceutical industry, including successfully guiding new drugs through research, development, and the commercialization process.

Christy J. Oliger. Ms. Oliger has served as a member of our Board since 2020. Until 2020, Ms. Oliger served in numerous leadership roles over twenty years at Genentech, Inc. (“Genentech”), a biotechnology company, including most recently as Senior Vice President of the Oncology Business Unit from 2017 to 2020, and Senior Vice President, Neuroscience and Rare Disease Business Unit at Genentech from 2014 to 2017. During her tenure with Genentech, Ms. Oliger also held a number of senior leadership roles in both commercial and research and development across a variety of therapeutic areas, including oncology, neurology, rare disease, respiratory, dermatology and immunology. Prior to Genentech, Ms. Oliger held management positions at Schering-Plough. Ms. Oliger has served on the board of directors of Nuvalent, Inc., a public biopharmaceutical company, since June 2025, where she also serves as a member of the audit committee, Vera Therapeutics, Inc., a public biotechnology company, since April 2024, where she also serves as a member of the nominating and corporate governance committee and chair of the commercialization committee, and Replimune Group Inc., a public biotechnology company, since December 2021, where she also serves on the research and development committee and is the chair of the compensation committee and the commercialization steering committee. Ms. Oliger served on the board of directors of Lava Therapeutics N.V., a public immuno-oncology company, where she also served on the audit committee and nominating and corporate governance committee, from March 2023 to November 2025, when it was acquired by XOMA Royalty Corporation, the board of directors of RayzeBio, Inc., a public radiopharmaceutical company, from September 2023 until April 2024 when it was acquired by Bristol Myers Squibb, the board of directors of Reata Pharmaceuticals, Inc., a public biopharmaceutical company, from April 2021 until September 2023, when it was acquired by Biogen Inc., and the board of directors of Sierra Oncology, Inc., a public biopharmaceutical company, from June 2021 until July 2022, when it was acquired by GSK plc. Ms. Oliger holds a bachelor’s degree in Economics from the University of California at Santa Barbara. We believe Ms. Oliger’s qualifications to serve on our Board include her more than thirty years of strategic and operational experience in the biopharmaceutical industry with broad commercial, portfolio management and leadership expertise, including in the oncology field.

Members of the Board of Directors Continuing in Office

For a Three-Year Term Expiring at the

2027 Annual Meeting of Stockholders (Class II)

Deepika R. Pakianathan, Ph.D. Dr. Pakianathan has served as a member of our Board since 2013. Since 2001, Dr. Pakianathan has been a Managing Member at Delphi Ventures, a venture capital firm focused on biotechnology and medical device investments, where she leads the firm’s biotechnology investment activities. Dr. Pakianathan also serves as the Chief Executive Officer of two biotechnology companies operating in stealth mode, one company since 2019 and the other company since August 2023. From 1998 to 2001, Dr. Pakianathan was a senior biotechnology banker at JPMorgan, a global investment bank, from 1997 to 1998, she was a research analyst covering biotechnology at Genesis Merchant Group Securities and from 1993 to 1997 she was a post-doctoral research scientist at Genentech. Dr. Pakianathan has served on the board of directors of Theravance Biopharma, Inc., a public biopharmaceutical company, since 2020, where she also serves as chair of the nominating and governance committee and a member of the audit committee and the development and commercialization committee, and Mereo Biopharma Group PLC, a public biopharmaceutical company, since 2019, where she also serves as chair of its audit committee and a member of the remuneration committee. In 2020, Dr. Pakianathan was appointed to the board of directors of Palleon Pharmaceuticals, Inc., a biotechnology company, where she serves as lead director and chair of the audit committee and the compensation committee. In January 2021, Dr. Pakianathan was appointed to the board of Freenome Holdings, Inc., a diagnostic

company, where she serves as chair of the audit committee and a member of the compensation committee. From 2020 to February 2021, Dr. Pakianathan served on the board of directors of Foresite Development Corp I, and from February 2021 to December 2021, Dr. Pakianathan served on the board of directors of Foresite Development Corp II, both public special purpose acquisition companies. Dr. Pakianathan also served on the board of directors of Calithera Biosciences, Inc., a public biopharmaceutical company, from 2010 to December 2023; the board of directors of Alder Biopharmaceuticals, Inc., a public biopharmaceutical company, from 2007 until 2019, when it was acquired by Lundbeck A/S; the board of directors of OncoMed Pharmaceuticals, Inc., a public biopharmaceutical company, from 2008 until 2019, when it was acquired by Mereo Biopharma Group PLC; and the board of directors of Alexza Pharmaceuticals, Inc., a public biopharmaceutical company, from 2004 to 2016, when it was acquired by Ferrer. Dr. Pakianathan holds a M.S. and Ph.D. from Wake Forest University, a B.Sc. from the University of Bombay, India and a M.Sc. from The Cancer Research Institute at the University of Bombay, India. We believe Dr. Pakianathan’s qualifications to serve on our Board include her experience as a chief executive officer, a venture capital investor and director of multiple biotechnology companies, as well as her experience as a biotechnology investment banker, research analyst and research scientist.

Richard Paulson, M.B.A. Mr. Paulson has served as our President and Chief Executive Officer since May 2021 and as a member of our Board since 2020. Prior to joining Karyopharm, Mr. Paulson was the Executive Vice President and Chief Executive Officer of Ipsen North America, a biopharmaceutical company, from 2018 to May 2021. Mr. Paulson was Vice President and General Manager, U.S. Oncology Business Unit at Amgen Inc. (“Amgen”), a public biotechnology company, from 2015 to 2018 and prior to that was Vice President, Marketing for Amgen’s U.S. Oncology Business, General Manager, Amgen Germany and General Manager of Amgen Central & Eastern Europe. Prior to Amgen, Mr. Paulson held a number of global leadership positions at Pfizer Inc. (“Pfizer”), including serving as General Manager of Pfizer South Africa and Pfizer Czech Republic. Mr. Paulson also previously held a variety of sales, marketing, and market access roles with increasing seniority at GlaxoWellcome plc in Canada. Mr. Paulson served as a member of the board of directors of bluebird bio, Inc., a public biotechnology company, from April 2023 to July 2025. Mr. Paulson has an M.B.A. from the University of Toronto, Canada and an undergraduate degree in commerce from the University of Saskatchewan, Canada. We believe Mr. Paulson’s qualifications to serve on our Board include his more than 25 years of global biopharmaceutical industry experience, as well as his achievements in leading and growing businesses, both in the U.S. and internationally, as well as his extensive knowledge of, and leadership of, our Company as our President and Chief Executive Officer.

Chen Schor, M.B.A., C.P.A. Mr. Schor has served as a member of our Board since 2020. Mr. Schor has served as the President, Chief Executive Officer and Director of Adicet Bio, Inc. (“Adicet Bio”), a public biotechnology company, since 2020. He held the role of President and Chief Executive Officer at resTORbio, Inc. (“resTORbio”) from 2016 until its merger with Adicet Bio in 2020. Prior to resTORbio, Mr. Schor served as President, Chief Executive Officer and Director of Synta Pharmaceuticals Corporation from 2014 until 2016. Previously, he served as Vice President, Global Branded Business Development and Pipeline Management at Teva Pharmaceuticals Industries Ltd. and held leadership positions at several emerging private and public companies. Before that, Mr. Schor was a Partner at Yozma Venture Capital, where he led the foundation and growth of multiple therapeutic companies from inception to commercial success. Mr. Schor has served on the board of directors of resTORbio/Adicet Bio since 2016 and on the board of directors of Alliance for Cancer Gene Therapy, a non-for-profit organization committed to advancing new cancer cell and gene therapies, since December 2021. Mr. Schor has also served as chair of the board of directors of Koslapp Therapeutics, Inc., a private company, since June 2025. He previously served on the board of directors and audit committee of Brainstorm Cell Therapeutics Inc., a public biotechnology company, from 2011 until 2020. Mr. Schor holds a B.A. in Biology and an M.B.A. from Tel Aviv University, a B.A. in Economics and Accounting from Haifa University and is a Certified Public Accountant. We believe Mr. Schor’s qualifications to serve on our Board include his substantial transactional and financial experience and extensive experience leading biotech companies across all stages, from formation and early-stage discovery to publicly traded multi-product companies.

Members of the Board of Directors Continuing in Office

For a Three-Year Term Expiring at the

2028 Annual Meeting of Stockholders (Class III)

Garen G. Bohlin. Mr. Bohlin has served as a member of our Board since 2013. Since 2012, Mr. Bohlin has focused exclusively on service on boards of directors and consulting. From 2010 until his retirement in 2012, he served as Executive Vice President of Constellation Pharmaceuticals, Inc. (“Constellation”), a biopharmaceutical company, which was private at that time. Prior to Constellation, Mr. Bohlin served as Chief Operating Officer of Sirtris Pharmaceuticals, Inc., from 2006 to 2009, which was acquired by GlaxoSmithKline plc. From 1999 to 2008, Mr. Bohlin served as President and Chief Executive Officer of Syntonix Pharmaceuticals, Inc. (“Syntonix”), which was acquired by Biogen Idec. Prior to Syntonix, Mr. Bohlin spent 14 years in executive management at Genetics Institute, Inc., which was acquired by Wyeth, and prior to that he was a partner at Arthur Andersen & Co., where he spent 13 years. Mr. Bohlin has served on the board of directors of Collegium Pharmaceutical, Inc., a public specialty pharmaceutical company, since 2015, where he also serves on the audit committee and compliance committee, and as Chairman of the board of directors of Curadel Surgical Innovations, Inc., a radiopharmaceutical company, since 2020. Mr. Bohlin previously served on the board of directors of Proteon Therapeutics, Inc., a public biopharmaceutical company, from 2014 to 2020, where he also served on the audit committee, compensation committee and nominating and corporate governance committee. He also previously served on the board of directors of Tetraphase Pharmaceuticals, Inc., a public biotechnology company, from 2010 to 2020, where he also served on the audit committee. Mr. Bohlin holds a B.S. in Accounting from the University of Illinois. We believe Mr. Bohlin’s qualifications to serve on our Board include his extensive industry and board experience, including his audit committee experience, with publicly traded and privately held biotechnology companies.

Zhen Su, M.D., M.B.A. Dr. Su has served as a member of our Board since August 2023. Dr. Su has served as Chief Executive Officer of Marengo Therapeutics, Inc. (“Marengo”), a clinical-stage biotechnology company, since July 2021. Prior to joining Marengo, Dr. Su served as Senior Vice President and U.S. & Global Head of Oncology Business Franchise of Merck KGaA, a multinational science and technology company, from 2020 to July 2021 and served as Senior Vice President, Global Head of Oncology Business Franchise from 2019 to May 2021. Dr. Su served as Chief Medical Officer of EMD Serono, Inc., a biopharmaceutical company, from 2017 to 2019. Dr. Su also held leadership roles with increasing responsibility at Sanofi Oncology, a global healthcare company, and GSK, a global biopharmaceutical company. Before his industry career, Dr. Su served on the faculty of Duke University Medical School, where he led early oncology clinical studies focusing on mRNA-based and cell-based immunotherapy and then the University of Florida, where he was the director of the Cell and Gene Therapy program. Dr. Su has served as a member of the board of directors of CytomX Therapeutics, Inc., a public biopharmaceutical company, since March 2024 and a member of the board of directors of Marengo since July 2021. He served as a member of the board of directors of Galvanize Therapeutics, Inc., a biomedical platform company, from July 2024 to July 2025. Dr. Su received his Doctor of Medicine from Technical University of Dresden in Germany and his M.B.A. from the University of Toronto in Canada. We believe Dr. Su’s qualifications to serve on our Board include his strong leadership and business acumen with clinical expertise in oncology, urology and immuno-oncology and over 20 years of experience in academic and pharmaceutical medicine including general management, clinical development, medical affairs and business development.

Former Directors who served in 2025

Mansoor Raza Mirza, M.D., served as a member of our Board from 2010 until September 2025. On September 5, 2025, Dr. Mirza notified us of his resignation from the Board, effective as of September 8, 2025.

OUR BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS THAT THE STOCKHOLDERS VOTE FOR THE ELECTION OF EACH OF MR. GREENE AND MS. OLIGER AS A CLASS I DIRECTOR.

CORPORATE GOVERNANCE

General

We believe that good corporate governance is important to ensure the long-term benefit of our stockholders. This section describes key corporate governance practices that we have adopted, including our Code of Ethics and Business Conduct, which applies to all of our officers, directors and employees, Corporate Governance Guidelines, and charters for our Board’s Audit Committee, Compensation Committee, Nominating, Corporate Governance & Compliance Committee, and Commercialization and Portfolio Committee. We have posted copies of our Code of Ethics and Business Conduct and the Corporate Governance Guidelines, as well as each of our committee charters, under the heading “Corporate Governance” in the “Investors” section of our website, www.karyopharm.com, which you can access free of charge. Information contained on the website is not incorporated by reference in, or considered part of, this proxy statement. We intend to disclose on our website any amendments to, or waivers from, our Code of Ethics and Business Conduct that are required to be disclosed by law or the Listing Rules of the Nasdaq Stock Market (“Nasdaq”). We will also provide copies of these documents as well as our other corporate governance documents, free of charge, to any stockholder upon written request to Karyopharm Therapeutics Inc., 85 Wells Avenue, Newton, Massachusetts 02459, Attention: Investor Relations.

Director Independence

Rule 5605 of the Nasdaq Listing Rules requires a majority of a listed company’s board of directors to be comprised of independent directors. In addition, the Nasdaq Listing Rules require that, subject to specified exceptions, each member of a listed company’s audit, compensation and nominations committees be independent and that audit and compensation committee members also satisfy independence criteria set forth in Rule 10A-3 and Rule 10C-1, respectively, under the Securities Exchange Act of 1934, as amended (the “Exchange Act”).

Under Rule 5605(a)(2) of the Nasdaq Listing Rules, a director will only qualify as an “independent director” if, in the opinion of our Board, that person does not have a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. In order to be considered independent for purposes of Rule 10A-3 of the Exchange Act, a member of an audit committee of a listed company may not, other than in his or her capacity as a member of the audit committee, the board of directors, or any other board committee, accept, directly or indirectly, any consulting, advisory, or other compensatory fee from the listed company or any of its subsidiaries or otherwise be an affiliated person of the listed company or any of its subsidiaries.

In addition, in affirmatively determining the independence of any director who will serve on a company’s compensation committee, Rule 10C-1 under the Exchange Act requires that a company’s board of directors consider all factors specifically relevant to determining whether a director has a relationship to such company which is material to that director’s ability to be independent from management in connection with the duties of a compensation committee member, including, but not limited to: (a) the source of compensation of the director, including any consulting, advisory or other compensatory fee paid by such company to the director; and (b) whether the director is affiliated with the company or any of its subsidiaries or affiliates.

Our Board has reviewed the composition of our Board and its committees and the independence of each director. Based upon information requested from and provided by each director concerning his or her background, employment and affiliations, including family relationships, our Board has determined that each of our directors, with the exception of Mr. Paulson, is an “independent director” as defined under Rule 5605(a)(2) of the Nasdaq Listing Rules. Our Board also determined that Messrs. Bohlin and Schor and Dr. Pakianathan, who currently comprise our Audit Committee; Dr. Pakianathan, Mr. Greene and Ms. Oliger, who currently comprise our Compensation Committee; and Messrs. Greene, Bohlin, and Schor, who currently comprise our Nominating, Corporate Governance & Compliance Committee, satisfy the independence standards for such committees established by the SEC and the Nasdaq Listing Rules, as applicable. Our Board also determined that Dr. Mirza, a former director, was an “independent director” prior to his resignation from our Board effective as of September 8, 2025.

There are no family relationships among any of our directors or executive officers.

Board Leadership Structure

Our bylaws and Corporate Governance Guidelines provide our Board with flexibility to combine or separate the positions of Chairman of the Board and Chief Executive Officer and/or to implement the role of Lead Independent Director in accordance with its determination that utilizing one or the other structure would be in the best interests of the Company.

At this time, we do not have a Chairman of the Board, though our Board appointed Mr. Greene to serve as Lead Independent Director in 2015. While our Board believes that oversight of the Company is the responsibility of our Board as a whole, and this responsibility can be properly discharged without a Chairman or Lead Independent Director, our Board determined that appointing Mr. Greene as Lead Independent Director would facilitate interactions between our Chief Executive Officer and the other independent directors and would enable the Board and the Company to utilize Mr. Greene’s breadth of experience across many strategic and operational matters in biotechnology companies.

Mr. Greene serves as a liaison between our President and Chief Executive Officer and our independent directors. He meets regularly and communicates directly with the independent directors outside the presence of management and reports any comments and concerns of the independent directors to our President and Chief Executive Officer. He also meets regularly with our senior management to discuss operational and strategic matters. Mr. Greene presides over executive sessions of the Board and provides our President and Chief Executive Officer with an annual review, as well as regular feedback, based on the consensus views collected from members of our Board.

While our President and Chief Executive Officer facilitates communications between members of our Board and works with management in the preparation of the agenda for each meeting of the Board, Mr. Greene also has an important role in establishing the agenda, determining what information is provided to our Board and coordinating with management to ensure that sufficient meeting time is allocated to each agenda item. Additionally, all of our directors are encouraged to make suggestions for agenda items or pre-meeting materials for meetings of our Board.

Our Board has concluded that the current leadership structure described above is appropriate at this time for the reasons stated above. However, our Board will continue to periodically review our leadership structure and may make such changes in the future, as it deems appropriate.

The Board’s Role in Risk Oversight

Our Board has responsibility for the oversight of the Company’s risk management processes and, either as a whole or through its committees, regularly discusses with management our major risk exposures, the potential impact of these risks on our business and the steps we take to manage them. The risk oversight process includes receiving regular reports from Board committees and members of senior management to enable our Board to understand the Company’s risk identification, risk management and risk mitigation strategies with respect to areas of potential material risk, including the Company’s corporate strategy, business objectives, compliance, financial condition, legal, regulatory, commercial, information technology and reputational risk. The committees of the Board execute their risk oversight responsibility for risk management as follows:

While each committee is responsible for evaluating certain risks and overseeing the management of such risks, the entire Board is regularly informed through committee reports about such risks. Matters of significant risk are considered by our Board as a whole.

Human Capital

We believe that the success of our business is fundamentally correlated to the execution of our business strategy and the achievement of our long-term objectives as well as our greatest asset, our employees. To that end, we have invested significant resources toward the attraction, retention and development of our people and fostering an inclusive and engaging workplace. To support these goals, our human capital management programs and initiatives underscore our core values (Innovation, Courage, Alignment and Accountability, Resiliency and Energy) and are designed to support employee well-being, professional development, competitive compensation and an inclusive culture.

To attract, retain and reward our employees, we provide competitive total rewards intended to support the financial, physical and emotional well-being of employees and their families. We currently offer equity awards to all new employees and additional equity and cash-based incentive opportunities in connection with our annual performance review process. Our equity and cash incentive plans are designed to align employee performance with the achievement of our corporate objectives and the creation of stockholder value. In addition, many of our employees are stockholders of our company through participation in an employee stock purchase plan, which provides employees with the opportunity to acquire common stock on a tax-advantaged basis. We also provide up to a 4% match of components of employee compensation to our Section 401(k) retirement savings plan.

We strive to provide our employees with a safe and healthy work environment and believe that the overall health, safety and wellness of our employees is important to our ability to execute our business plans. As such, we provide our employees and their families with access to a variety of comprehensive benefits programs, including benefits that provide protection and security to employees and their eligible dependents. In alignment with our KaryoFlex philosophy, we offer flexible time off to our employees, which is designed to support work-life balance. Our full-time employees are all eligible to participate in our health, vision, dental, life, and long-term disability insurance plans. To encourage employees to keep up with routine medical care and participate in our wellness program, we fund a Health Reimbursement Account for participating employees that partially covers employee deductibles. To help employees cover medical expenses on a pre-tax basis, we also offer Flexible Spending Accounts. In addition, we offer a High Deductible Health Plan coupled with a Health Savings Account in which we provide initial funding and employees may also contribute to this tax-advantaged savings account to pay for qualified expenses. Employees may also participate in a Limited Purpose Flexible Spending Account for dental and vision expenses. All employees have access to complimentary virtual fitness programs, mental and emotional health support services, caregiving resources for childcare, tutoring, eldercare, pet care, and other needs as well as a monthly wellness stipend to support a broad range of well-being activities.

We encourage and support the growth and development of our employees and, where practical, seek to fill positions internally through lateral and promotional opportunities. Continual learning and career development is supported through ongoing performance and development discussions, a formal mentorship program, tuition assistance, and employee and leadership training programs focused on both technical and professional skills. We also offer customized training engagements and seminars aligned with employees’ current and anticipated roles, providing development opportunities across the organization and supporting retention of key talent.

Further, we strongly believe in fostering a culture of inclusiveness and employee well-being and are committed to maintaining a workplace that values diverse backgrounds, perspectives, and experiences. We strive to bring together employees with a wide variety of backgrounds, skills and culture and encourage all employees to maintain a work environment in which differences are respected. We have established relationships with external affinity organizations, including professional groups supporting LGBTQ+ individuals, women and Latino professionals in the biotechnology industry, to broaden our talent networks and enhance employee engagement.

We have created a women’s Employee Resource Group (“ERG”) that provides opportunities for connection, mentorship, and professional development for women and allies across the organization. We have also established key working relationships with local universities and operate an annual internship program that supports early-career talent development.

Corporate Responsibility

We are highly committed to policies and practices focused on environmental, social, and governance (“ESG”), positively impacting our social community and maintaining and cultivating good corporate governance. By focusing on ESG policies and practices, we believe we can affect a meaningful and positive change in our community and continue to cultivate our open and inclusive collaborative culture.

Some of our 2025 initiatives included continuing support for the scientific, medical, patient, and local communities in which we operate, including patient education, public health, quality of healthcare, and disease awareness. We also enable our employees to participate in various charity events, including walks, races, and other events that impact change in the communities of the patients we serve. We offer an employee volunteer time off program to support volunteer activities that enhance the communities in which we live and work while providing our employees the paid time to help those around them. This allows our employees to support causes that are meaningful to them and their families and align with our mission, goals, and vision.

Board of Directors Meetings

Our Board met 14 times during the year ended December 31, 2025, including telephonic meetings. During 2025, each of our incumbent directors attended or participated telephonically in 75% or more of the aggregate of (a) the total number of meetings of the Board held during the period for which he or she served as a director and (b) the total number of meetings of all committees on which the director served during the periods that he or she served.

We do not have a formal policy regarding attendance by members of our Board at our annual meeting of stockholders. Three members of our Board serving at the time attended our 2025 annual meeting of stockholders held on May 28, 2025.

Committees of the Board of Directors

Our Board currently has four standing committees: the Audit Committee; the Compensation Committee; the Nominating, Corporate Governance & Compliance Committee; and the Commercialization and Portfolio Committee. Each of these committees has a written charter approved by our Board. A copy of each charter can be found under the heading “Corporate Governance” in the “Investors” section of our website at www.karyopharm.com. The following table provides membership information for the current composition of these committees:

“*” indicates Lead Independent Director

“C” indicates Chair of the committee

“M” indicates member of the committee

Audit Committee

The members of our Audit Committee currently include Messrs. Bohlin (Chair) and Schor and Dr. Pakianathan. Our Board has determined that each of Messrs. Bohlin and Schor and Dr. Pakianathan qualifies as an “audit committee financial expert” within the meaning of SEC regulations and the Nasdaq Listing Rules. In making this determination, our Board considered the formal education and nature and scope of Mr. Bohlin and Mr. Schor’s previous experience, coupled with past or present service on various audit committees. For the relevant experience which qualifies Dr. Pakianathan as an audit committee financial expert, please see her biographical information under “Proposal 1: Election of Directors – Information Regarding Directors” section of this proxy statement. Our Audit Committee assists our Board in its oversight of the quality and integrity of our accounting, auditing and financial reporting process, the audits of our financial statements and our independent registered public accounting firm, including its appointment, compensation, and retention. The Audit Committee met eight times during 2025, including telephonic meetings. Pursuant to its charter, the Audit Committee’s general responsibilities currently include, among other things, the following:

Compensation Committee

The members of our Compensation Committee currently include Dr. Pakianathan (Chair), Mr. Greene and Ms. Oliger. Our Compensation Committee assists our Board in the discharge of its responsibilities relating to the compensation of our executive officers and Board members. The Compensation Committee met four times during 2025, including telephonic meetings. Pursuant to its charter, the Compensation Committee’s general responsibilities currently include, among other things, the following:

The Compensation Committee generally meets at least four times annually and with greater frequency if necessary. The agenda for each meeting is usually developed by the chair of the Compensation Committee, in consultation with our President and Chief Executive Officer and Chief Human Resources Officer. The Compensation Committee meets regularly in executive session. However, from time to time, various members of management and other employees, as well as outside advisors or consultants, may be invited by the Compensation Committee to make presentations, to provide financial or other background information or advice or to otherwise participate in Compensation Committee meetings. No officer may participate in, or be present during, any deliberations or determinations of the Compensation Committee regarding the compensation for such officer. The charter of the Compensation Committee grants the Compensation Committee full access to all of our books, records, facilities, and personnel, as well as authority to obtain, at our expense, advice and assistance from internal and external legal, accounting, or other advisors and consultants, and other external resources that the Compensation Committee considers necessary or appropriate in the performance of its duties. In particular, the Compensation Committee has the sole authority to retain compensation consultants to assist in its evaluation of executive and director compensation, including the authority to approve the consultant’s reasonable fees and other retention terms.

In addition, under its charter, the Compensation Committee may form, and delegate authority to, subcommittees, consisting of independent directors, as it deems appropriate. The Compensation Committee can also delegate to one or more executive officers the authority to grant equity awards to certain employees, as further described in its charter and subject to the terms of our equity plans. The Compensation Committee has, at times, delegated to our President and Chief Executive Officer the authority to make equity awards under our 2022 Plan within approved guidelines to employees in connection with annual, promotional, recognition or new hire grants, as applicable, other than grants to employees with a title of Senior Vice President or above (including our NEOs). The number of stock options, restricted stock units (“RSUs”) or performance-based RSUs (“PSUs”), as applicable, our President and Chief Executive Officer may grant under the 2022 Plan to any individual must be within the range set by our Compensation Committee for these awards. The independent directors of our Board have also delegated to a subcommittee of the Board the authority to make equity awards to new employees under the Karyopharm Therapeutics Inc. 2022 Inducement Stock Incentive Plan, as amended (the “2022 Inducement Plan”), pursuant to guidelines similar to those applicable to the delegation to our President and Chief Executive Officer under our 2022 Plan.

Historically, the Compensation Committee has approved and, in the case of our President and Chief Executive Officer, the Compensation Committee has recommended to the Board and the Board has approved, adjustments to executives’ annual compensation, determined variable cash compensation and equity awards, and established new performance objectives at one or more meetings held during the last quarter of the year and the first quarter of the following year. However, the Compensation Committee also considers matters related to individual compensation, such as compensation for new executive hires, as well as high-level strategic issues, such as the efficacy of our compensation strategy, potential modifications to that strategy, and new trends, plans, or approaches to compensation, at various meetings throughout the year. The Compensation Committee is responsible for making determinations, or making recommendations to our Board, regarding compensation of executive officers, making changes to pre-approved salary ranges, salary increase budgets, equity award budgets, variable cash compensation targets, incentive payments, and pre-approved equity ranges for new hires and high performers, and making material changes to benefits offered to our employees. In determining compensation of executive officers other than our President and Chief Executive Officer, the Compensation Committee, with input from its compensation consultant, also considers the recommendations of our President and Chief Executive Officer. In addition, the Compensation Committee, with input from its compensation consultant, makes recommendations to our Board regarding the compensation of our President and Chief Executive

Officer and our non-employee directors. The Compensation Committee also administers our equity-based plans and compensation programs.

Nominating, Corporate Governance & Compliance Committee

The members of our Nominating, Corporate Governance & Compliance Committee currently include Messrs. Greene (Chair), Bohlin, and Schor. The Nominating, Corporate Governance & Compliance Committee met six times during 2025, including telephonic meetings. Pursuant to its charter, the Nominating, Corporate Governance & Compliance Committee’s general responsibilities currently include, among other things, the following:

Each year, a self-evaluation process is conducted by the Company under the oversight of the Nominating, Corporate Governance & Compliance Committee. This process includes the completion of an extensive questionnaire by each director for the Board and each committee of the Board on which he or she sits, covering topics such as Board and committee leadership structure, composition and effectiveness, quality of Board and committee materials and discussions, priority agenda items, schedule sufficiency, and Board processes. The results of the self-evaluation questionnaires are reviewed by the Nominating, Corporate Governance & Compliance Committee, which then reports any key findings and observations to the full Board. The Board, led by the Lead Independent Director, then discusses the evaluation reports to determine what, if any, actions or improvements should be undertaken in the near-term and long-term. The Board and committee evaluations are discussed in executive session to allow for additional candid discussion.

Commercialization and Portfolio Committee

The members of our Commercialization and Portfolio Committee currently include Ms. Oliger (Chair) and Drs. Pakianathan and Su. Dr. Mirza served as a member of the Commercialization and Portfolio Committee until his resignation from the Board, effective as of September 8, 2025. The Commercialization and Portfolio Committee met four times during 2025, including telephonic meetings. Pursuant to its charter, the Commercialization and Portfolio Committee’s general responsibilities currently include, among other things, the following:

Code of Ethics and Business Conduct

We have adopted a written Code of Ethics and Business Conduct that applies to our directors, officers and employees, including our principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions. We have posted on our website, www.karyopharm.com, a current copy of the Code of Ethics and Business Conduct and all disclosures that are required by law or Nasdaq Listing Rules concerning any amendments to, or waivers from, any provision of the Code of Ethics and Business Conduct. Information contained on the website is not incorporated by reference in, or considered part of, this proxy statement.

Director Nomination Process

Director Qualifications

In evaluating director nominees, the Nominating, Corporate Governance & Compliance Committee considers, among other things, the following factors:

The Nominating, Corporate Governance & Compliance Committee’s goal is to assemble a Board that brings to the Company a variety of perspectives and skills derived from high quality business and professional experience. Moreover, the Nominating, Corporate Governance & Compliance Committee believes that the background and qualifications of the members of our Board, considered as a group, should provide a significant breadth of experience, knowledge and abilities to assist the Board in fulfilling its responsibilities.

The Nominating, Corporate Governance & Compliance Committee has not adopted a formal policy with respect to a fixed set of specific minimum qualifications for its candidates for membership on the Board, provided that director nominees are considered by the Nominating, Corporate Governance & Compliance Committee consistent with our Corporate Governance Guidelines, which include certain criteria for nomination as a director of our Board. The Nominating, Corporate Governance & Compliance Committee considers such criteria and other factors, including those set forth above, as it may deem are in the best interests of the Company and its stockholders. The Nominating, Corporate Governance & Compliance Committee further believes it is appropriate for at least one member of our Board to meet the criteria for an “audit committee financial expert” as that phrase is defined under the regulations promulgated by the SEC, and that a majority of the members of our Board be independent as required under the Nasdaq qualification standards. The Nominating, Corporate Governance & Compliance Committee believes it is appropriate for our President and Chief Executive Officer to serve as a member of our Board. Our directors’ performance and qualification criteria are reviewed periodically by the Nominating, Corporate Governance & Compliance Committee.

Identification and Evaluation of Nominees for Directors

The Nominating, Corporate Governance & Compliance Committee identifies nominees for director by first evaluating the current members of our Board willing to continue in service. Current members with qualifications and skills that are consistent with the Nominating, Corporate Governance & Compliance Committee’s criteria for service on the Board and who are willing to continue in service are considered for re-nomination, balancing the value of continuity of service by existing members of our Board with that of obtaining a new perspective or expertise. The Nominating, Corporate Governance & Compliance Committee reviews the overall service provided by these directors to the Company during their terms, including the number of meetings attended, level of participation, quality of performance and any other relationships and transactions that might impair the directors’ independence, as well as the results of the Board’s self-evaluation, which is generally conducted annually, to determine whether to recommend them to the Board for nomination for a new term.

If any member of our Board does not wish to continue to serve on the Board or if our Board decides not to re-nominate a member for re-election, and our Board seeks to fill such vacancy, the Nominating, Corporate Governance & Compliance Committee identifies a new nominee that meets the criteria above. The Nominating, Corporate Governance & Compliance Committee generally inquires of our Board and members of management for their recommendations and may also review the composition and qualification of the boards of directors of our competitors or seek input from industry experts or analysts. The Nominating, Corporate Governance & Compliance Committee then reviews the qualifications, experience, and background of suggested candidates. Final candidates, if other than our current directors, are interviewed by the members of the Nominating, Corporate Governance & Compliance Committee and by certain of our other independent directors and executive management. In making its determinations, the Nominating, Corporate Governance & Compliance Committee evaluates each individual in the context of our Board as a whole, with the objective of assembling a group that can best contribute to the success of the Company and represent stockholder interests through the exercise of sound judgment. After review and deliberation of all feedback and data, the Nominating, Corporate Governance & Compliance Committee makes its recommendation to our Board. The Nominating, Corporate Governance & Compliance Committee has previously engaged a search firm to conduct a search for additional directors with specific expertise to join our Board. The Nominating, Corporate Governance & Compliance Committee may in the future engage third-party search firms in those situations where particular qualifications are required or where existing contacts are not sufficient to identify an appropriate candidate.

We have not received director candidate recommendations from our stockholders and do not have a formal policy regarding consideration of such recommendations. However, any recommendations received from stockholders will be evaluated in the same manner that potential nominees suggested by board members, management, or other parties are evaluated. Stockholders wishing to recommend a director candidate for consideration by our Nominating, Corporate Governance & Compliance Committee must submit such recommendation in writing to our principal executive offices at Karyopharm Therapeutics Inc., 85 Wells Avenue, Newton, Massachusetts 02459, Attention: Corporate Secretary. Such recommendation must be received by us no earlier than January 21, 2027 and no later than February 19, 2027. Such submissions must state the nominee’s name, together with appropriate biographical information and background materials, and information with respect to the stockholder or group of stockholders making the recommendation, including the number of shares of common stock owned by such stockholder or group of stockholders. We may require any proposed nominee to furnish such other information as we may reasonably require to determine the eligibility of the

proposed nominee to serve as an independent director or that could be material to a reasonable stockholder’s understanding of the independence, or lack thereof, of such proposed nominee.

Stockholders also have the right under our bylaws to directly nominate director candidates, without any action or recommendation on the part of our Nominating, Corporate Governance & Compliance Committee or the Board, by following the procedures set forth below under “Stockholder Proposals.” If our Board determines to nominate a stockholder-recommended candidate and recommends his or her election, then his or her name will be included in our proxy statement and proxy card for the next annual meeting of stockholders. Otherwise, candidates nominated by stockholders in accordance with the procedures set forth in the bylaws will not be included in our proxy statement for the next annual meeting.

Limits on Director Service on Other Company Boards

We have a highly effective and engaged Board, and we believe that our directors’ service on other companies’ boards enable them to contribute valuable knowledge and perspective to our Board activities. Nonetheless, the Board is sensitive to the external obligations of its directors and the potential for overboarding to compromise their ability to effectively serve the Company. Our Corporate Governance Guidelines limit each director’s service on other boards of public companies to a number that permits them, given their individual circumstances, to responsibly perform all director duties. Directors who serve as chief executive officers of a public company may not serve on more than two public company boards other than the board of the company of which he or she is chief executive officer. All other directors may not serve on more than five public company boards.

Communications with Our Board of Directors

Stockholders seeking to communicate with our Board must submit their written comments to Karyopharm Therapeutics Inc., 85 Wells Avenue, Newton, Massachusetts 02459, Attention: Corporate Secretary. The Corporate Secretary will forward such communications to each member of our Board; provided that, if in the opinion of our Corporate Secretary it would be inappropriate to send a particular stockholder communication to a specific director, such communication will only be sent to the remaining directors (subject to the remaining directors concurring with such opinion).

Director Compensation

We seek to attract exceptional people to serve on our Board and, therefore, our policy is to compensate non-employee members of our Board competitively relative to members of the board of directors of comparable companies. The Board believes that including equity as a part of our director compensation helps align the interest of directors with those of our stockholders. Accordingly, our director compensation is a mix of cash and equity compensation. The Board also believes that it is appropriate for the Lead Independent Director and the Chair of each standing committee of the Board to receive additional compensation for the additional workload and time commitment required for Board members who serve in such capacities. The non-employee members of our Board are also reimbursed for travel, lodging, and other reasonable expenses incurred in attending Board or committee meetings. Directors who are also employees, such as Mr. Paulson, do not receive any compensation for service on the Board in addition to compensation received for their service as our employees.

The following table reflects the cash and equity compensation that our directors were eligible to receive under the terms of our Non-Employee Director Compensation Policy in effect during 2025, which did not change as compared to the 2024 director compensation program.

The stock options granted to our non-employee directors for service on our Board have an exercise price equal to the fair market value of our common stock on the date of grant, expire ten years after the date of grant, and are subject to the director’s continued service to the Company on the applicable vesting dates. In addition, our 2022 Plan includes limitations on director compensation, including, with respect to non-employee directors, a maximum aggregate amount of cash paid and value of awards granted (calculated based on grant date fair value for financial reporting purposes) equal to, in the case of any incumbent director, $750,000 in any calendar year, and, in the case of any newly elected or appointed director, $1,000,000 in such director’s initial year of election or appointment. Exceptions to these limitations may only be made by our Board in extraordinary circumstances provided that the non-employee director receiving any additional compensation does not participate in the decision to award such compensation. The foregoing limitations in non-employee director compensation do not apply to cash or equity awards granted to a non-employee director in his or her capacity as an advisor to the Company.

The following table sets forth the compensation paid to or earned by our non-employee directors during the year ended December 31, 2025.

Limitation of Liability and Indemnification

Our certificate of incorporation limits the personal liability of directors and officers for breach of fiduciary duty to the maximum extent permitted by the Delaware General Corporation Law (the “DGCL”) and provides that no director or officer will have personal liability to us (in the case of directors) or to our stockholders (in the case of directors and officers) for monetary damages for any breach of fiduciary duty as a director or officer. However, these provisions do not eliminate or limit the liability of any of our directors or officers:

Any amendment to or repeal of these provisions will not eliminate or reduce the effect of these provisions in respect of any act, omission or claim that occurred or arose prior to such amendment or repeal. If the DGCL is amended to provide for further limitations on the personal liability of directors or officers of corporations, then the personal liability of our directors or officers will be further limited to the greatest extent permitted by the DGCL.

In addition, our certificate of incorporation provides that we must indemnify our directors and officers, and we must advance expenses, including attorneys’ fees, to our directors and officers in connection with legal proceedings, subject to very limited exceptions.

We maintain an insurance policy that covers certain liabilities of our directors and officers arising out of claims based on acts or omissions in their capacities as directors or officers. In addition, we have entered into indemnification agreements with our directors. These indemnification agreements require us, among other things, to indemnify each such director for some expenses, including attorneys’ fees, judgments, fines, and settlement amounts incurred by him or her in any action or proceeding arising out of his or her service as one of our directors.

Certain of our non-employee directors may, through their relationships with their employers, be insured and/or indemnified against certain liabilities incurred in their capacity as members of our Board.

Insofar as indemnification for liabilities arising under the Securities Act of 1933, as amended (the “Securities Act”) may be permitted to directors, executive officers or persons controlling us, in the opinion of the SEC, such indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.

Report of the Audit Committee of the Board of Directors

The Audit Committee oversees the Company’s financial reporting process on behalf of the Board. We have reviewed the Company’s audited consolidated financial statements for the year ended December 31, 2025 and discussed them with Company management and Ernst & Young LLP, the Company’s independent registered public accounting firm for the year ended December 31, 2025.

We have received from, and discussed with, Ernst & Young LLP, which is responsible for expressing an opinion on the conformity of the Company’s audited consolidated financial statements with accounting principles generally accepted in the United States, its judgments as to the quality, not just the acceptability, of the Company’s accounting principles and such other matters as are required to be discussed with the Audit Committee under generally accepted auditing standards, including the matters required to be discussed by the applicable requirements of the Public Company Accounting Oversight Board (the “PCAOB”), and the SEC. In addition, we have discussed with Ernst & Young LLP its independence from management and the Company, have received from Ernst & Young LLP the written disclosures and the letter required by applicable requirements of the PCAOB regarding its communications with us concerning independence, and have considered the compatibility of non-audit services with the auditors’ independence.

Based on the review and discussions referred to above, we recommended to the Board of Directors that the audited consolidated financial statements be included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025.

This report of the Audit Committee is not “soliciting material,” shall not be deemed “filed” with the SEC and shall not be incorporated by reference by any general statement incorporating by reference this proxy statement into any filing under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, whether made before or after the date hereof and irrespective of any general incorporation language in any such filing, except to the extent that we specifically incorporate this information by reference, and shall not otherwise be deemed filed under such acts.

The foregoing report has been furnished by the Audit Committee.

PROPOSAL 2:

APPROVAL OF AN AMENDMENT TO OUR 2022 EQUITY INCENTIVE PLAN, AS AMENDED, TO INCREASE THE NUMBER OF SHARES OF OUR COMMON STOCK AVAILABLE FOR ISSUANCE THEREUNDER BY 3,000,000 SHARES

We are seeking stockholder approval to amend our 2022 Equity Incentive Plan, as amended (the “2022 Plan”) to increase the number of shares of common stock reserved for issuance under the 2022 Plan by 3,000,000 shares. No other amendments are being made to the 2022 Plan. Based on the recommendation of the Compensation Committee, on April 9, 2026, our Board approved the fourth amendment to the 2022 Plan, subject to stockholder approval (the “Amendment”). If stockholders approve this Amendment, we will continue to be able to make equity awards, including potential retention awards, which we believe are critical for attracting, motivating, rewarding and retaining a talented team who will contribute to our success.

Reasons Why Stockholders Should Approve the Amendment

Equity Awards Motivate, Retain and Incentivize Employees. We are a commercial-stage pharmaceutical company focused on marketing XPOVIO in its approved indications and developing and seeking regulatory approval of selinexor as an oral agent targeting multiple high unmet need cancer indications, including our lead clinical programs in myelofibrosis and endometrial cancer and our other late-stage clinical program in multiple myeloma. We are at a critical stage in our Company’s development and we believe that it is imperative that we motivate, retain, and incentivize our current employees as we continue to commercialize XPOVIO and further our efforts to bring a new treatment option for patients with myelofibrosis following recently announced clinical trial results from our Phase 3 clinical trial to treat patients with myelofibrosis, which met one of the two co-primary endpoints, as well as completing enrollment in and announcing expected topline results in mid-2026 from our Phase 3 clinical to treat patients with endometrial cancer.

As of March 30, 2026, only 95,975 shares remained available for future grant under the 2022 Plan, which is insufficient to make the critical, market-based grants needed to motivate, retain and incentivize our employees. Equity compensation is a critical component of our overall compensation program and recent operational and financial challenges have made it more difficult to effectively recruit, retain and incentivize talent. In light of the significant challenges we navigated in 2025 and in anticipation of key clinical, regulatory and commercial objectives in 2026, we intend to implement a broad-based retention program designed to help ensure continued motivation, retention and incentivization of our employees during this critical period. While this program is still in development, we expect this program to include performance-based equity awards to eligible employees. If the Amendment is not approved, we will be significantly constrained in our ability to make any future equity grants, which will, among other things, limit our ability to implement an effective retention program. In such circumstances, we may be required to increase the cash component of our compensation and retention programs, an approach we believe would be less effective in attracting, motivating, retaining and incentivizing our workforce and one that would strain our limited financial resources, potentially impacting our ability to service our debt obligations and pursue our growth objectives. In addition, the inability to offer competitive equity compensation would place us at a significant disadvantage relative to the companies with whom we compete for specialized talent and would increase the risk of attrition of key personnel critical to achieving our near-term clinical and regulatory objectives.

Accordingly, we believe approval of the Amendment is in the best interests of the Company and our stockholders and is vital to our ability to navigate these current challenges; motivate, retain and incentivize key talent; and position us for long-term success.

Broad-based Eligibility for Equity Awards. We believe that all of our employees are important in our continued efforts to bring XPOVIO to patients with cancer who can benefit from our drug as well as in the successful completion of and potential regulatory submissions for our ongoing clinical trials. Therefore, our equity incentive program is broad-based, with all eligible employees in good standing historically receiving annual equity awards as part of our annual performance review based upon level, performance and contribution as well as periodic retention awards. We believe that using equity as a means of compensation and retention broadly best aligns the interests of all of our employees with the interests of our stockholders by linking their compensation to our growth and the creation of stockholder value. Furthermore, equity awards have strong retention value since our Board typically grants awards to employees that

generally vest over a multi-year period. Accordingly, employees must remain with us during the vesting period in order to realize the potential benefits of their equity awards.

Aligns with our Pay-for-Performance Compensation Philosophy. We believe that equity compensation is fundamentally performance-based. As the value of our stock appreciates, our employees will receive greater compensation at the same time that our stockholders are receiving a greater return on their investment. Conversely, if the stock price does not appreciate following the grant of an equity award, then our employees would not receive any compensation with respect to stock options and would receive lower compensation than intended with respect to RSUs.

Aligns Employee and Director Interests with Stockholder Interests. Providing our employees and non-employee directors with compensation in the form of equity directly aligns the interests of those employees and directors with the interests of our stockholders. If the Amendment is approved by our stockholders, we will be able to continue granting equity incentives that foster this alignment between our employees and non-employee directors and our stockholders. If, however, the Amendment is not approved, we may have to restructure existing compensation programs, which will likely necessitate the replacement of components of compensation historically awarded in equity with cash, which may not necessarily align employee interests with those of stockholders as effectively as equity awards do. If we were to replace equity awards with cash, our cash reserves would be diverted away from our XPOVIO commercialization efforts as well as our clinical development programs and regulatory approval efforts, which may shorten our cash runway and negatively impact our ability to maximize the value of our multiple myeloma franchise as well as the timing and progress of our ongoing Phase 3 trials, and in turn, impair stockholder value.

We Are Mindful of the Dilution Associated with our Equity Compensation Practices. We understand that our equity compensation needs must be balanced against the dilutive effect our equity compensation program has on our stockholders. Our Compensation Committee and Board strive to thoughtfully manage long-term stockholder dilution, burn rate and stock-based compensation expense while maintaining our ability to attract, retain and motivate our workforce. We review market data on equity compensation with the Compensation Committee’s independent compensation consultant and the Compensation Committee on a regular basis with the goal of providing competitive pay packages for all levels of employees, including our executives, and aligning with the compensation practices of our peers. We actively manage dilution. Shares used to pay the exercise price of an award are not returned to the equity plan pool. Our Board, after weighing these considerations, believes the proposed dilution to stockholders as a result of the Amendment is judicious and sustainable and, importantly, critical to meet our business goals.

Consistent with Stockholder Interests and Sound Corporate Governance. As described under the heading “Sound Governance Features of the Amended 2022 Plan” and more thoroughly below, the 2022 Plan, as amended by the Amendment (the “Amended 2022 Plan”), was purposefully designed to include features that are consistent with the interests of our stockholders and sound corporate governance.

Why We Are Requesting Stockholder Approval of an Amendment to the 2022 Plan

Background

The 2022 Plan is our existing equity incentive plan and was originally approved by our Board on April 4, 2022 and by our stockholders on May 19, 2022, and most recently amended by our stockholders on May 28, 2025. The 2022 Plan is critical to our ability to continue to grant equity awards to all of our employees (other than to newly hired employees who we expect will generally receive grants made under the 2022 Inducement Plan). To date, we have granted RSUs, PSUs and stock options under the 2022 Plan.

In consultation with WTW, our Compensation Committee determined the requested number of shares provided for in the Amendment, based on its assessment of the equity level deemed necessary to motivate, retain and incentivize employees and the Committee’s assessment of the magnitude of increase that our stockholders would likely find appropriate. If stockholders approve the Amendment, subject to adjustment in the event of stock splits and other similar events, awards may be made under the Amended 2022 Plan, for up to a number of shares of common stock equal to the sum of: (i) 4,456,666 shares of common stock; and (ii) such additional number of shares of common stock (up to 948,749) as is equal to the sum of (x) the number of shares of common stock that were reserved for issuance under our 2013 Stock Incentive Plan (the “2013 Plan”), which remained available for grant immediately prior to May 19, 2022, the date our

stockholders originally approved the 2022 Plan and (y) the number of shares of common stock subject to awards granted under our 2013 Plan that were outstanding as of such date which awards expire, terminate or are otherwise surrendered, cancelled, forfeited or repurchased by the Company at their original issuance price pursuant to a contractual repurchase right (subject, however, in the case of incentive stock options to any limitations under the Internal Revenue Code of 1986, as amended, and any regulations thereunder (the “Code”)).

For newly hired employees, we have historically relied on the inducement grant exception under Nasdaq Listing Rule 5635(c)(4), including pursuant to the 2022 Inducement Plan, to grant nonstatutory stock options and/or RSUs (“Inducement Awards”) to all of our eligible newly hired full-time employees. Because the number of shares available for issuance under the 2022 Plan has been (and will continue to be even if the Amendment is approved) carefully calibrated to enable us to make equity grants to our current employees, the 2022 Inducement Plan will remain in effect even if the Amendment is approved and we expect to continue utilizing the 2022 Inducement Plan for all our new hire equity grants. As of March 30, 2026, there were 38,711 shares remaining available for the grant of new awards under the 2022 Inducement Plan.

The following table includes information regarding all of our (i) outstanding equity awards under all of our equity compensation plans under which shares of common stock may be issued, other than our Amended & Restated ESPP, (ii) outstanding Inducement Awards that were granted as stock options or RSUs outside of our equity compensation plans, (iii) outstanding warrants and pre-funded warrants, Convertible Senior Notes due 2028 (the “2028 Notes”) and Convertible Senior Notes due 2029 (the “2029 Notes”) under which shares of common stock may be issued upon exercise or conversion, as applicable, (iv) shares available for future awards under the 2022 Plan (prior to the Amendment) and the 2022 Inducement Plan and (v) the number of shares of common stock outstanding, each as of March 30, 2026:

If this proposal is approved by our stockholders, we intend to register the additional shares reserved for issuance under the 2022 Plan by filing a Registration Statement on Form S-8 as soon as practicable following such approval.

Our Board believes approval of the Amendment is in the best interests of the Company and its stockholders and recommends a vote “FOR” the approval of the Amendment.

The remainder of this Proposal 2 includes:

Sound Governance Features of the Amended 2022 Plan

The Amended 2022 Plan includes several features that are designed to protect the interests of our stockholders, align awards with such interests, and reflect sound corporate governance practices. Certain of these features are highlighted below, and these and other terms of the plan are more fully described in the Description of the Amended 2022 Plan further below as well as in the copy of the 2022 Plan and the Amendment in Appendix A to this proxy statement.

No Evergreen. The Amended 2022 Plan does not include an “evergreen” or other provision that provides for automatic increases in the number of shares available for grant under the plan and therefore any increase to the maximum share reserve in the Amended 2022 Plan is subject to approval by our stockholders, allowing our stockholders to have a say in our equity compensation programs.

Minimum Vesting Provisions. Minimum vesting provisions of one year generally apply to all awards to participants, with the exception of awards for up to 5% of the shares of stock reserved under the Amended 2022 Plan.

Clawback Policy. In accepting an award under the Amended 2022 Plan, participants agree to be bound by any clawback policy the Company has in effect or may adopt in the future.

No Automatic Vesting of Awards on a Change in Control Event; Double-trigger Acceleration of Vesting upon a Change in Control. The Amended 2022 Plan does not provide for the automatic vesting of awards in connection with a change in control event. Instead, the Amended 2022 Plan includes “double-trigger” acceleration, pursuant to which options, RSU awards and restricted stock awards will become fully vested and nonforfeitable if the holder of such award is terminated without cause or resigns for good reason within one year following a change in control event. For more information on the vesting treatment for equity awards granted under the Amended 2022 Plan, please see the section titled “Employment, Severance and Change in Control Arrangements” contained elsewhere in this proxy statement.

No liberal share recycling. The Amended 2022 Plan prohibits the re-granting of (i) shares withheld or delivered to satisfy the exercise price of an award or to satisfy tax withholding obligations, (ii) shares that were subject to a SAR, and were not issued upon the net settlement or net exercise of such award, or (iii) shares repurchased on the open market using proceeds from the exercise of an award.

No Repricing of Options or SARs. The Amended 2022 Plan prohibits the direct or indirect repricing of stock options or SARs without stockholder approval.

No Discounted Options or SARs. All options and SARs must have an exercise or measurement price that is at least equal to the fair market value of the underlying common stock on the date of grant.

No Reload Options or SARs. No options or SARs granted under the Amended 2022 Plan may contain a provision entitling the award holder to the automatic grant of additional options or SARs in connection with any exercise of the original option or SAR.

No Dividend Equivalents on Options or SARs. No options or SARs granted under the Amended 2022 Plan may provide for the payment or accrual of dividend equivalents.

Dividends and Dividend Equivalents on Restricted Stock, Restricted Stock Units and Other-Stock Based Awards Not Paid Until Award Vests. Under the Amended 2022 Plan, any dividends or dividend equivalents paid with respect to restricted stock, RSUs or other stock-based awards will be subject to the same restrictions on transfer and forfeitability as the award with respect to which they are paid.

Limit on Non-Employee Director Compensation. Under the Amended 2022 Plan, the maximum aggregate amount of cash earned or paid and value of awards (calculated based on grant date fair value for financial reporting purposes) granted to any non-employee director in any calendar year may not exceed $750,000 in the case of an incumbent director. However, such maximum aggregate amount shall not exceed $1,000,000 in any calendar year for any individual non-employee director in such non-employee director’s initial year of election or appointment. Exceptions to these limitations may only be made by our Board in extraordinary circumstances provided that the non-employee director receiving any additional compensation does not participate in the decision to award such compensation.

Material Amendments Require Stockholder Approval. Stockholder approval is required prior to an amendment of the Amended 2022 Plan that would (i) materially increase the number of shares authorized (other than as provided under the Amended 2022 Plan with respect to certain corporate events or substitute awards), (ii) expand the types of awards that may be granted, or (iii) materially expand the class of participants eligible to participate.

Administered by an Independent Committee. The Amended 2022 Plan is administered by the Compensation Committee, as delegated by our Board. The Compensation Committee is made up entirely of independent directors.

Information Regarding Overhang and Burn Rate

Consistent with our historical practice, in developing our share request for the Amended 2022 Plan and analyzing the impact of utilizing equity as a means of compensation on our stockholders, we considered both our “overhang” and our “burn rate”.

Overhang is a measure of potential dilution which we define as the sum of (i) the total number of shares underlying all equity awards outstanding and (ii) the total number of shares available for future award grants, divided by the sum of (a) the total number of shares underlying all equity awards outstanding, (b) the total number of shares available for future awards, and (c) the total number of shares of common stock outstanding. As of March 30, 2026, there were 1,781,658 shares underlying all equity awards outstanding (assuming maximum performance for PSUs), 95,975 shares available for future awards under the 2022 Plan (assuming maximum performance for PSUs), 38,711 shares available for future awards under the 2022 Inducement Plan and 22,543,316 shares of common stock were outstanding. Accordingly, our overhang at March 30, 2026 was 7.83%. If the 3,000,000 shares proposed to be authorized for grant under the Amended 2022 Plan are included in the calculation, our overhang on March 30, 2026 would have been 17.90%. For purposes of the above calculations, the number of shares of common stock outstanding does not include the 29,954,175 shares of common stock issuable upon exercise of outstanding warrants and pre-funded warrants or pursuant to conversion of the 2029 Notes and 2028 Notes. If such shares of common stock issuable upon exercise of outstanding warrants and pre-funded warrants or pursuant to conversion of the 2029 Notes and 2028 Notes are included in the calculations, our overhang at March 30, 2026 would have been 3.52% on a fully-diluted basis and 8.56% on a fully-diluted basis if the 3,000,000 shares proposed to be authorized for grant under the Amended 2022 Plan are also included in the calculation.

Net burn rate provides a measure of the potential dilutive impact of our equity award program, which we define as the number of shares covered by awards granted in a given fiscal year minus shares subject to outstanding equity awards forfeited and expired during that year, divided by the weighted-average number of shares of common stock outstanding for that year. We believe a net burn rate measure (that is, a burn rate calculated to reflect forfeitures and expirations of awards) indicates the rate at which we actually create potential future stockholder dilution. The following table sets forth information regarding historical awards granted and awards forfeited or expired in each of the 2023 through 2025 fiscal periods, and the corresponding annual net burn rate, for each of such three fiscal years, as well as the average net burn rate for those three years:

*Amounts presented in this table for 2024 and 2023 may differ from previously reported amounts, including amounts reported in the 2025 Annual Report, as a result of adjustments to reflect the Company’s 1-for-15 reverse stock split of our common stock effected on February 25, 2025.

(1) Included in “Forfeitures and Expirations” for 2025 are 220,143 stock options, 131,128 RSUs and 46,693 PSUs; for 2024 are 183,293 stock options, 73,104 RSUs and 16,881 PSUs; and for 2023 are 317,950 stock options, 94,971 RSUs and 22,319 PSUs. The PSU amounts assume maximum performance.

The following table provides information regarding the grants and forfeitures of PSUs as well as the PSUs for which the performance criteria was certified as attained, earned and vested during the past three completed fiscal years:

We recognize that equity awards dilute existing stockholders, and, therefore, we and our Compensation Committee are mindful to responsibly manage our equity compensation program. We believe our historical three-year burn rate is reasonable for a number of reasons, including our broad-based equity program in place to retain and motivate top talent in what is a competitive labor market for biotech companies, drive successful expansion of our commercial business and progress our clinical development and related regulatory submissions for our ongoing clinical development programs. It is critical that we grant competitive, market-driven equity awards to our employees and as a result, unlike many companies, our equity is not primarily limited to our executive leadership team. Rather, our equity compensation program has always been and will continue to be a key component in our ability to pay market-competitive compensation to all of our eligible

employees, not just those in leadership positions, and to motivate employees at every level of the organization to drive stockholder value.

We are disciplined in our use of equity and view our compensation program as a key tool to align employees and directors with long-term stockholder interests. We carefully manage dilution by actively monitoring our share reserve and burn rate, and we grant equity awards with a clear focus on retention, motivation, and performance. Our equity strategy is grounded in governance, designed to support our ability to attract and retain top talent in a competitive market, in order to deliver value to our stockholders.

Equity Compensation Plan Information

For more information on our equity compensation plans, please see the section titled “Executive Compensation – Equity Compensation Plan Information” contained elsewhere in this proxy statement.

Description of the Amended 2022 Plan

The following is a brief summary of the Amended 2022 Plan. A copy of each of the 2022 Plan, Amendment No. 1, Amendment No. 2, Amendment No. 3 and the Amendment is attached in Appendix A to this proxy statement. References to our Board in this summary include the Compensation Committee or any similar committee or sub-committee or the officers of the Company to the extent that the Board’s powers or authority under the Amended 2022 Plan have been delegated to such committee or officers, in accordance with the Amended 2022 Plan.

Types of Awards; Eligibility; Shares Available for Awards; Share Counting Rules

The Amended 2022 Plan provides for the grant of incentive stock options intended to qualify under Section 422 of the Code, non-statutory stock options, SARs, restricted stock, RSUs, other stock-based awards and cash awards as described below (collectively, “awards”). Employees, directors consultants and advisors to the Company are eligible to receive awards under the Amended 2022 Plan. The term “Company” and similar terms include any of the Company’s present or future parent or subsidiary corporations as defined in Sections 424(e) or (f) of the Code and any other business venture (including, without limitation, joint venture or limited liability company) in which the Company has a controlling interest, as determined by the Board.

Subject to adjustment in the event of stock splits, stock dividends and other similar events, awards may be made under the Amended 2022 Plan (any or all of which awards may be in the form of incentive stock options) for up to a number of shares of common stock equal to the sum of: (i) 4,456,666 shares of common stock; and (ii) such additional number of shares of common stock (up to 948,749) as is equal to the sum of (x) the number of shares of common stock reserved for issuance under the 2013 Plan that remained available for grant immediately prior to the date our stockholders originally approved the 2022 Plan and (y) the number of shares of common stock subject to awards granted under our 2013 Plan that were outstanding as of such date which awards expire, terminate or are otherwise surrendered, cancelled, forfeited or repurchased by the Company at their original issuance price pursuant to a contractual repurchase right (subject, however, in the case of incentive stock options to any limitations under the Code). Shares of common stock issued under the Amended 2022 Plan may consist in whole or in part of authorized but unissued shares or treasury shares.

The Amended 2022 Plan provides that the maximum aggregate amount of cash and value of awards (calculated based on grant date fair value for financial reporting purposes) granted to any individual non-employee director in any calendar year may not exceed $750,000 in the case of an incumbent director. However, such maximum aggregate amount shall not exceed $1,000,000 in any calendar year for any individual non-employee director in such non-employee director’s initial year of election or appointment. Moreover, fees paid by the Company on behalf of any non-employee director in connection with regulatory compliance and any amounts paid to a non-employee director as reimbursement of an expense will not count against this limit. Exceptions to this limitation may only be made by our Board in extraordinary circumstances provided that any non-employee director receiving additional compensation does not participate in the decision to award such compensation. This limitation does not apply to cash or awards granted to a non-employee director in his or her capacity as an advisor or consultant to the Company.

For purposes of counting the number of shares available for the grant of awards under the Amended 2022 Plan, all shares of common stock covered by SARs will be counted against the number of shares available for the grant of awards. However, SARs that may be settled only in cash will not be so counted. Similarly, to the extent that an RSU award may be settled only in cash, no shares will be counted against the shares available for the grant of awards under the Amended 2022 Plan. In addition, if we grant a SAR in tandem with an option for the same number of shares of our common stock and provide that only one such award may be exercised (“tandem SAR”), only the shares covered by the option, and not the shares covered by the tandem SAR, will be so counted, and the expiration of one in connection with the other’s exercise will not restore shares to the Amended 2022 Plan.

Shares covered by awards under the Amended 2022 Plan that expire or are terminated, surrendered, or cancelled without having been fully exercised or are forfeited in whole or in part (including as the result of shares subject to such award being repurchased by us at the original issuance price pursuant to a contractual repurchase right) or that result in any shares not being issued (including as a result of a SAR or an RSU that was settleable either in cash or in stock actually being settled in cash) will again be available for the grant of awards under the Amended 2022 Plan (subject, in the case of incentive stock options, to any limitations under the Code). In the case of the exercise of a SAR, the number of shares counted against the shares available for the grant of awards under the Amended 2022 Plan will be the full number of shares subject to the SAR multiplied by the percentage of the SAR actually exercised, regardless of the number of shares actually used to settle the SAR upon exercise, and the shares covered by a tandem SAR will not again become available for grant upon the expiration or termination of the tandem SAR.

Shares of common stock that are delivered (by actual delivery, attestation, or net exercise) to us by a participant to purchase shares of common stock upon exercise of an award or to satisfy tax withholding obligations (including shares retained from the award creating the tax obligation) will not be added back to the number of shares available for the future grant of awards under the Amended 2022 Plan. Shares repurchased by us on the open market using proceeds from the exercise of an award will also not increase the number of shares available for future grant of awards under the Amended 2022 Plan.

In connection with a merger or consolidation of an entity with us or our acquisition of property or stock of an entity, our Board may grant awards under the Amended 2022 Plan in substitution for any options or other stock or stock-based awards granted by such entity or an affiliate thereof on such terms as our Board determines appropriate in the circumstances, notwithstanding any limitation on awards contained in the Amended 2022 Plan. No such substitute awards will count against the overall share limit, except as required by reason of Section 422 and related provisions of the Code.

Descriptions of Awards

Options. A participant who is awarded an option receives the right to purchase a specified number of shares of common stock at a specified exercise price and subject to the other terms and conditions that are specified in connection with the award agreement. An option that is not intended to be an “incentive stock option” is a “non-statutory stock option.” Options may not be granted at an exercise price that is less than 100% of the fair market value of our common stock on the date of grant. If our Board approves the grant of an option with an exercise price to be determined on a future date, the exercise price may not be less than 100% of the fair market value of our common stock on that future date. Under present law, incentive stock options may not be granted at an exercise price less than 110% of the fair market value in the case of stock options granted to participants who hold more than 10% of the total combined voting power of all classes of our stock or any of our subsidiaries. Under the terms of the Amended 2022 Plan, options may not be granted for a term in excess of ten years (and, under present law, five years in the case of incentive stock options granted to participants who hold greater than 10% of the total combined voting power of all classes of our stock or any of our subsidiaries).

The Amended 2022 Plan permits participants to pay the exercise price of options using one or more of the following manners of payment: (i) payment by cash or by check, (ii) except as may otherwise be provided in the applicable award agreement or approved by our Board, in connection with a “cashless exercise” through a broker, (iii) to the extent provided in the applicable award agreement or approved by our Board, and subject to certain conditions, by delivery to us (either by actual delivery or attestation) of shares of common stock owned by the participant valued at their fair market value, (iv) to the extent provided in an applicable non-statutory stock option award agreement or approved by our Board, by delivery of a notice of “net exercise” as a result of which we will retain a number of shares of common stock otherwise

issuable pursuant to the stock option equal to the aggregate exercise price for the portion of the option being exercised divided by the fair market value of our common stock on the date of exercise, (v) to the extent permitted by applicable law and provided for in the applicable award agreement or approved by our Board, by any other lawful means (but not by a promissory note of the participant), or (vi) by any combination of these forms of payment. No option granted under the Amended 2022 Plan may contain a provision entitling the participant to the automatic grant of additional options in connection with any exercise of the original option. No options granted under the Amended 2022 Plan may provide for the payment or accrual of dividend equivalents.

Stock Appreciation Rights. A participant who is awarded a SAR receives, upon exercise, a number of shares of our common stock, or cash (or a combination of shares of our common stock and cash) determined by reference to appreciation, from and after the date of grant, in the fair market value of a share of our common stock over the measurement price. The Amended 2022 Plan provides that the measurement price of a SAR may not be less than 100% of the fair market value of our common stock on the date the SAR is granted (provided, however, that if our Board approves the grant of a SAR effective as of a future date, the measurement price shall not be less than 100% of the fair market value on such future date) and that SARs may not be granted with a term in excess of 10 years. No SARs granted under the Amended 2022 Plan may contain a provision entitling the participant to the automatic grant of additional SARs in connection with any exercise of the original SAR. No SARs granted under the Amended 2022 Plan may provide for the payment or accrual of dividend equivalents.

Limitation on Repricing of Options or SARs. With respect to options and SARs, unless such action is approved by stockholders or otherwise permitted under the terms of the Amended 2022 Plan in connection with certain changes in capitalization and reorganization events, we may not (1) amend any outstanding option or SAR granted under the Amended 2022 Plan to provide an exercise price or measurement price per share that is lower than the then-current exercise price or measurement price per share of such outstanding option or SAR, (2) cancel any outstanding option or SAR (whether or not granted under the Amended 2022 Plan) and grant in substitution therefor new awards under the Amended 2022 Plan (other than certain substitute awards issued in connection with a merger or consolidation of an entity with us or an acquisition by us, described above) covering the same or a different number of shares of our common stock and having an exercise price or measurement price per share lower than the then-current exercise price or measurement price per share of the canceled option or SAR, (3) cancel in exchange for a cash payment any outstanding option or SAR with an exercise price or measurement price per share above the then-current fair market value of our common stock, or (4) take any other action under the Amended 2022 Plan that constitutes a “repricing” within the meaning of the rules of the Nasdaq Stock Market or any other exchange or marketplace on which the Company’s stock is listed or traded.

Restricted Stock Awards. A participant who is granted a restricted stock award is entitled to acquire shares of our common stock, subject to our right to repurchase all or part of such shares at their issue price or other stated or formula price (or to require forfeiture of such shares if issued at no cost) in the event that the conditions specified in the applicable award are not satisfied prior to the end of the applicable restriction period established for such award. Any dividends (whether paid in cash, stock or property) declared and paid by us with respect to shares of restricted stock will be paid to the participant only if and when such shares become free from the restrictions on transferability and forfeitability that apply to such shares. No interest will be paid on unvested dividends.

Restricted Stock Unit Awards. A participant who is granted an RSU award is entitled to receive shares of our common stock, or cash equal to the fair market value of such shares or a combination thereof, to be delivered at the time such award vests or on a deferred basis pursuant to the terms and conditions established by our Board. Our Board may provide that settlement of RSUs will be deferred, on a mandatory basis or at the election of the participant, in a manner that complies with Section 409A of the Code. A participant has no voting rights with respect to any RSU. An RSU award agreement may provide the applicable participant with the right to receive an amount equal to any dividends or other distributions declared and paid on an equal number of outstanding shares of our common stock. Any such dividend equivalents may be settled in cash and/or shares of our common stock and will be subject to the same restrictions on transfer and forfeitability as the RSUs with respect to which such dividend equivalents are awarded. No interest will be paid on dividend equivalents.

Other Stock-Based Awards. Under the Amended 2022 Plan, our Board may grant other awards of shares of our common stock, and other awards that are valued in whole or in part by reference to, or are otherwise based on, shares of our common stock or other property, having such terms and conditions as our Board may determine. We refer to these

types of awards as other stock-based awards. Other stock-based awards may be available as a form of payment in settlement of other awards granted under the Amended 2022 Plan or as payment in lieu of compensation to which a participant is otherwise entitled. Other stock-based awards may be paid in shares of our common stock or in cash, as our Board may determine. The award agreement of an other stock-based award may provide the participant who receives that award of an other stock-based award with the right to receive dividend equivalents. Dividend equivalents may be settled in cash and/or shares of our common stock and will be subject to the same restrictions on transfer and forfeitability as the other stock-based award with respect to which they are awarded. No interest will be paid on dividend equivalents.

Cash Awards. Under the Amended 2022 Plan, the Board has the right to grant cash-based awards including awards subject to performance conditions.

Performance Conditions. Awards under the Amended 2022 Plan may be made subject to the achievement of performance goals. Our Board may specify that the degree of granting, vesting and/or payout of any award subject to performance-based vesting conditions will be subject to the achievement of one or more of the following performance measures established by the Board, which may be based on the relative or absolute attainment of specified levels of one or any combination of the following measures (and which may be determined pursuant to generally accepted accounting principles (“GAAP”) or on a non-GAAP basis, as determined by the Board): (i) the entry into an arrangement or agreement with a third party for the development, commercialization, marketing or distribution of products, services or technologies, or for conducting a research program to discover and develop a product, service or technology, and/or the achievement of milestones under such arrangement or agreement, including events that trigger an obligation or payment right; (ii) achievement of domestic and international regulatory milestones, including the submission of filings required to advance products, services and technologies in clinical development and the achievement of approvals by regulatory authorities relating to the commercialization of products, services and technologies; (iii) the achievement of discovery, preclinical and clinical stage scientific objectives, discoveries or inventions for products, services and technologies under research and development; (iv) the entry into or completion of a phase of clinical development for any product, service or technology, such as the entry into or completion of phase 1, 2 and/or 3 clinical trials; (v) the consummation of debt or equity financing transactions, or acquisitions of business, technologies and assets; (vi) new product or service releases; (vii) the achievement of qualitative or quantitative performance measures set forth in operating plans approved by the Board from time to time; (viii) specified levels of product sales, net income, earnings before or after discontinued operations, interest, taxes, depreciation and/or amortization, operating profit before or after discontinued operations and/or taxes, sales, sales growth, earnings growth, cash flow or cash position, gross margins, stock price, market share, return on sales, assets, equity or investment; (ix) improvement of financial ratings; (x) achievement of balance sheet or income statement objectives; (xi) total stockholder return or stock price; (xii) other comparable measures of financial and operational performance; and/ or (xiii) any other measure selected by the Board. Such goals may reflect absolute entity or business unit performance or a relative comparison to the performance of a peer group of entities or other external measure of the selected performance criteria and may be absolute in their terms or measured against or in relationship to other companies comparably, similarly or otherwise situated. The Board may specify that such performance measures will be adjusted to exclude any one or more of: (I) extraordinary items; (II) gains or losses on the dispositions of discontinued operations; (III) the cumulative effects of changes in accounting principles; (IV) the write-down of any asset; (V) fluctuation in foreign currency exchange rates; (VI) charges for restructuring and rationalization programs; (VII) non-cash, mark-to-market adjustments on derivative instruments; (VIII) amortization of purchased intangibles; (IX) the net impact of tax rate changes; (X) non-cash asset impairment charges; (XI) gains on extinguishment of the tax receivable agreement; and (XII) any other factors as the Board may determine. Such performance measures: (A) may vary by participant and may be different for different awards; (B) may be particular to a participant or the department, branch, line of business, subsidiary or other unit in which the participant works; and (C) may cover such period as may be specified by the Board. The Board will have the authority to make equitable adjustments to the performance goals in recognition of unusual or non-recurring events affecting the Company or the financial statements of the Company, in response to changes in applicable laws or regulations or to account for items of gain, loss or expense determined to be extraordinary or unusual in nature or infrequent in occurrence or related to the disposal of a segment of a business or related to a change in accounting principles. Our Board may adjust the cash or number of shares payable pursuant to a performance award, and the Board may, at any time, waive the achievement of the applicable performance measures. Notwithstanding its designation as a performance award, no option or SAR will provide for the payment or accrual of dividend equivalents, any dividends declared and paid by the Company with respect to shares of restricted stock will be subject to the same dividend rules for restricted stock awards not designated as a performance award and any right to receive dividend equivalents on an award of RSUs and other stock-based awards will be subject to the same dividend equivalent rules for such awards that are not designated as a performance award.

Eligibility to Receive Awards

All of our employees, officers, and directors, as well as our consultants and advisors, are eligible to receive awards under the Amended 2022 Plan, if selected by the Board. However, incentive stock options may only be granted to our employees, employees of our present or future parent or subsidiary corporations as defined in Sections 424(e) or (f) of the Code, and employees of any other entities the employees of which are eligible to receive incentive stock options under the Code.

Transferability of Awards

Awards may not be sold, assigned, transferred, pledged or otherwise encumbered by a participant, either voluntarily or by operation of law, except by will or the laws of descent and distribution or, other than in the case of an incentive stock option, pursuant to a qualified domestic relations order. During the life of the participant, awards are exercisable only by the participant. However, except with respect to awards that are subject to Section 409A of the Code and incentive stock options, our Board may permit or provide in an award for the gratuitous transfer of the award by the participant to or for the benefit of any immediate family member, family trust or other entity established for the benefit of the participant and/or an immediate family member thereof if we would be eligible to use a Form S-8 under the Securities Act for the registration of the sale of the common stock subject to such award to the proposed transferee. Further, we are not required to recognize any such permitted transfer until such time as the permitted transferee has, as a condition to the transfer, delivered to us a written instrument in form and substance satisfactory to us confirming that such transferee will be bound by all of the terms and conditions of the award. None of the restrictions described in this paragraph prohibit a transfer from the participant to the Company.

No Rights as a Stockholder; Clawback

No participant or designated beneficiary will have any rights as a stockholder with respect to any shares of common stock to be distributed with respect to an award granted under the Amended 2022 Plan until becoming a record holder of such shares, subject to the terms of an award agreement. In accepting an award under the Amended 2022 Plan, a participant agrees to be bound by any clawback policy that the Company has in effect or may adopt in the future, including without limitation the Company’s Dodd-Frank Compensation Recovery Policy.

Plan Benefits

As of March 30, 2026, approximately 274 persons were eligible to receive awards under the Amended 2022 Plan, including all three NEOs, three other executive officers who are not NEOs, 219 employees (excluding NEOs and other executive officers), all six non-employee directors (excluding our President and Chief Executive Officer who is an executive officer), 43 consultants and zero advisors (excluding consultants), in each case, if selected by the Board.

Awards Granted Under 2022 Plan

The following table sets forth information about equity awards granted under the 2022 Plan since adoption of the 2022 Plan by our stockholders on May 19, 2022 through March 30, 2026, exclusive of the 2026 director grants, which are set forth under the heading “New Plan Benefits Table”, to the individuals and groups described in the table below:

On March 30, 2026, the last reported sale price of our common stock on the Nasdaq Global Select Market was $5.30.

New Plan Benefits Table

The granting of awards under the Amended 2022 Plan is discretionary, and we cannot now determine the number or type of awards to be granted in the future to any particular person or group, other than as set forth below. As noted above, we are developing a retention program; however, the terms have not been finalized and the implementation and any allocation under such program remains at the discretion of our Compensation Committee.

We are obligated to grant each of our non-employee directors an option to purchase 4,600 shares immediately following our 2026 annual stockholder meeting under the terms of our Non-Employee Director Compensation Policy. Based upon our Non-Employee Director Compensation Policy, future awards of options to purchase shares will be made to non-employee directors in years subsequent to 2026 on the date of future annual stockholder meetings.

Administration

The Amended 2022 Plan will be administered by our Board. Our Board has the authority to grant awards and to adopt, amend and repeal the administrative rules, guidelines and practices relating to the Amended 2022 Plan that it deems advisable and to construe and interpret the provisions of the Amended 2022 Plan and any award agreements entered into under the Amended 2022 Plan. Our Board may correct any defect, supply any omission or reconcile any inconsistency in the Amended 2022 Plan or any award. All actions and decisions by our Board with respect to the Amended 2022 Plan and any awards made under the Amended 2022 Plan will be made in our Board’s discretion and will be final and binding on all persons having or claiming any interest in the Amended 2022 Plan or in any award.

Pursuant to the terms of the Amended 2022 Plan, our Board may delegate any or all of its powers under the Amended 2022 Plan to one or more committees or subcommittees of our Board. The Board has authorized the Compensation Committee to administer certain aspects of the Amended 2022 Plan. Awards granted to non-employee directors must be granted and administered by a committee of the Board, all of the members of which are independent directors as defined by Section 5605(a)(2) of the Nasdaq Marketplace Rules.

Subject to any requirements of applicable law, the Board may delegate to one or more officers the power to grant awards (subject to any limitations under the Amended 2022 Plan) to employees or officers and to exercise such other powers under the Amended 2022 Plan as the Board may determine, provided that the Board shall fix the terms of awards to be granted by such officers, the maximum number of shares subject to awards that the officers may grant, and the time period in which such awards may be granted; and provided further, that no officer shall be authorized to grant awards to any “executive officer” (as defined by Rule 3b-7 under the Exchange Act), or to any “officer” (as defined by Rule 16a-1(f) under the Exchange Act).

Subject to applicable limitations contained in the Amended 2022 Plan, the Board, the Compensation Committee, or any other committee or subcommittee or officer to whom the Board has delegated authority pursuant to the Amended 2022 Plan, as the case may be, selects the recipients of awards and determines (i) the number of shares of common stock, cash or other consideration covered by awards and the terms and conditions of such awards, including the dates upon which such awards become exercisable or otherwise vest, (ii) the exercise or measurement price of awards, if any, and (iii) the duration of awards.

Except as otherwise provided in the Amended 2022 Plan, each award under the Amended 2022 Plan may be made alone or in addition or in relation to any other award. The terms of each award need not be identical, and our Board need not treat participants uniformly. Our Board will determine the effect on an award of the disability, death, termination or other cessation of employment or service, authorized leave of absence or other change in the employment or other service status of a participant, and the extent to which, and the period during which, the participant (or the participant’s legal representative, conservator, guardian or designated beneficiary) may exercise rights or receive any benefits under an award.

The Board may at any time provide that any award shall become immediately exercisable in whole or in part, free from some or all restrictions or conditions or otherwise realizable in whole or in part, as the case may be. Subject to the preceding sentence, no award under the Amended 2022 Plan shall vest earlier than the first anniversary of its date of grant, unless such award is granted in lieu of salary, bonus or other compensation otherwise earned by or payable to the participant; provided, that, such limitation will not apply to awards granted, in the aggregate, for up to 5% of the maximum number of authorized shares under the Amended 2022 Plan.

In the event of any stock split, reverse stock split, stock dividend, recapitalization, combination of shares, reclassification of shares, spin-off or other similar change in capitalization or event, or any dividend or distribution to holders of our common stock, other than an ordinary cash dividend, we are required to make equitable adjustments (or make substituted awards, as applicable), in the manner determined by our Board, to (i) the number and class of securities available under the Amended 2022 Plan, (ii) the share counting rules set forth in the Amended 2022 Plan, (iii) the number and class of securities and exercise price per share of each outstanding option, (iv) the share- and per-share provisions and the measurement price of each outstanding SAR, (v) the number of shares subject to and the repurchase price per share subject to each outstanding award of restricted stock, and (vi) the share and per-share-related provisions and the purchase price, if any, of each outstanding RSU award and each outstanding other stock-based award. In the event we effect a split of our common stock by means of a stock dividend and the exercise price of and the number of shares subject to an outstanding option are adjusted as of the date of the distribution of the dividend (rather than as of the record date for such dividend), then a participant who exercises an option between the record date and the distribution date for such stock dividend shall be entitled to receive, on the distribution date, the stock dividend with respect to the shares of common stock acquired upon such option exercise, notwithstanding the fact that such shares were not outstanding as of the close of business on the record date for such stock dividend.

Subject to applicable law, we will indemnify and hold harmless each director, officer, employee or agent to whom any duty or power relating to the administration or interpretation of the Amended 2022 Plan has been or will be delegated against any cost or expense (including attorneys’ fees) or liability (including any sum paid in settlement of a claim with our Board’s approval) arising out of any act or omission to act concerning the Amended 2022 Plan unless arising out of such person’s own fraud or bad faith.

Amendment of awards. Except as otherwise provided under the Amended 2022 Plan with respect to repricing outstanding stock options or SARs and with respect to actions requiring stockholder approval, our Board may amend, modify or terminate any outstanding award, including but not limited to, substituting therefor another award of the same or a different type, changing the date of exercise or realization, and converting an incentive stock option to a non-statutory stock option, provided that the participant’s consent to any such action will be required unless our Board determines that the action, taking into account any related action, does not materially and adversely affect the participant’s rights under the Amended 2022 Plan or the change is otherwise permitted under the terms of the Amended 2022 Plan in connection with certain corporate events.

Reorganization Events

The Amended 2022 Plan contains provisions addressing the consequences of any reorganization event. A reorganization event is defined under the Amended 2022 Plan as (a) any merger or consolidation of us with or into another entity as a result of which all of our common stock is converted into or exchanged for the right to receive cash, securities or other property, or is canceled, (b) any transfer or disposition of all of our common stock for cash, securities or other property pursuant to a share exchange or other transaction or (c) our liquidation or dissolution.

Provisions Applicable to Awards Other than Restricted Stock. Under the Amended 2022 Plan, if a reorganization event occurs, our Board may take any one or more of the following actions as to all or any (or any portion of) outstanding awards other than restricted stock on such terms as our Board determines (except to the extent specifically provided otherwise in an applicable award agreement or another agreement between a participant and us): (1) provide that such awards shall be assumed, or substantially equivalent awards shall be substituted, by the acquiring or succeeding corporation (or an affiliate thereof), (2) upon written notice to a participant, provide that all of the participant’s unvested awards will be forfeited immediately before the reorganization event and/or that all of the participant’s unexercised awards will terminate immediately prior to the consummation of such reorganization event unless exercised by the participant (to the extent then exercisable) within a specified period following the date of such notice, (3) provide that outstanding awards shall become exercisable, realizable, or deliverable, or restrictions applicable to an award shall lapse, in whole or in part prior to or upon such reorganization event, (4) in the event of a reorganization event under the terms of which holders of our common stock will receive upon consummation thereof a cash payment for each share surrendered in the reorganization event, which we refer to as the Acquisition Price, make or provide for a cash payment to participants with respect to each award held by a participant equal to (A) the number of shares of our common stock subject to the vested portion of the award (after giving effect to any acceleration of vesting that occurs upon or immediately prior to such reorganization event) multiplied by (B) the excess, if any, of (I) the Acquisition Price over (II) the exercise,

measurement or purchase price of such award and any applicable tax withholdings, in exchange for the termination of such award, provided, that if the Acquisition Price per share (as determined by our Board) does not exceed the exercise price of the award, then the award will be canceled without any payment of consideration, (5) provide that, in connection with our liquidation or dissolution, awards shall convert into the right to receive liquidation proceeds (if applicable, net of the exercise, measurement or purchase price thereof and any applicable tax withholdings) and (6) any combination of the foregoing.

Our Board is not obligated to treat all awards, all awards held by a participant, or all awards of the same type, identically. Certain RSU awards that are subject to Section 409A of the Code will be settled in accordance with the terms of the applicable award agreement or as otherwise specified in the Amended 2022 Plan. Our Board, with reasonable notice to participants holding options or SARs, may impose a limitation on the ability of these participants to exercise their awards for the minimum number of days prior to the closing of the reorganization event as is reasonably necessary to facilitate the orderly closing of the reorganization event.

Provisions Applicable to Restricted Stock. Upon the occurrence of a reorganization event other than our liquidation or dissolution, our repurchase and other rights with respect to outstanding restricted stock will inure to the benefit of our successor and will, unless our Board determines otherwise, apply to the cash, securities or other property which our common stock was converted into or exchanged for pursuant to such reorganization event in the same manner and to the same extent as they applied to such restricted stock. However, our Board may either provide for termination or deemed satisfaction of such repurchase or other rights under the instrument evidencing any restricted stock or any other agreement between a participant and us, either initially or by amendment or provide for forfeiture of such restricted stock if issued at no cost. Upon the occurrence of a reorganization event involving our liquidation or dissolution, except to the extent specifically provided to the contrary in the instrument evidencing any award of restricted stock or any other agreement between the participant and us, all restrictions and conditions on all restricted stock then outstanding shall automatically be deemed terminated or satisfied.

Change in Control Events

The Amended 2022 Plan contains provisions addressing the consequences of any change in control event. A change in control event is defined under the Amended 2022 Plan as: (A) the acquisition by an individual, entity or group (within the meaning of Section 13(d)(3) or 14(d)(2) of the Exchange Act), referred to herein as a Person, of beneficial ownership of any of our capital stock if, after such acquisition, such Person beneficially owns (within the meaning of Rule 13d-3 promulgated under the Exchange Act) 50% or more of the combined voting power of our then-outstanding securities entitled to vote generally in the election of directors, referred to herein as the Outstanding Company Voting Securities; provided, however, that for the purposes of the preceding provision, the following acquisitions shall not constitute a change in control event: (1) any acquisition directly from us or (2) any acquisition by any corporation pursuant to a Business Combination (as defined below) which complies with clauses (x) and (y) of subsection (C) of this definition; or (B) such time as the Continuing Directors (as defined below) do not constitute a majority of the Board (or, if applicable, the board of directors a successor corporation to us), where the term “Continuing Director” means at any date a member of the Board (x) who was a member of the Board on the date of the initial adoption of the 2022 Plan by the Board or (y) who was nominated or elected subsequent to such date by at least a majority of the directors who were Continuing Directors at the time of such nomination or election or whose election to the Board was recommended or endorsed by at least a majority of the directors who were Continuing Directors at the time of such nomination or election; or (C) the consummation of a merger, consolidation, reorganization, recapitalization or share exchange involving us or a sale or other disposition of all or substantially all of our assets of us (a “Business Combination”), unless, immediately following such Business Combination, each of the following two conditions is satisfied: (x) all or substantially all of the individuals and entities who were the beneficial owners of the Outstanding Company Voting Securities immediately prior to such Business Combination beneficially own, directly or indirectly, more than 50% of the combined voting power of the then-outstanding securities entitled to vote generally in the election of directors of the resulting or acquiring corporation in such Business Combination (which shall include, without limitation, a corporation which as a result of such transaction owns the Company or substantially all of the Company’s assets either directly or through one or more subsidiaries) in substantially the same proportions as their ownership of the Outstanding Company Voting Securities immediately prior to such Business Combination and (y) no Person beneficially owns, directly or indirectly, 50% or more of the combined voting power of the then-outstanding securities of such corporation entitled to vote generally in the election of directors (except to the extent that such ownership existed prior to the Business Combination); or (D) our liquidation or dissolution.

Provisions Applicable to Options. Notwithstanding the provisions with respect to the treatment of the options in a reorganization event, except to the extent specifically provided to the contrary in an award agreement or any other agreement between a participant and us, each option shall be immediately exercisable in full if, on or prior to the first anniversary of the date of the consummation of the change in control event, the participant’s employment with us or the acquiring or succeeding corporation is terminated for “good reason” by the participant or is terminated without “cause” (each, as defined below) by us or the acquiring or succeeding corporation.

Provisions Applicable to Restricted Stock. Notwithstanding the provisions with respect to the treatment of the restricted stock in a reorganization event, except to the extent specifically provided to the contrary in an award agreement or any other agreement between a participant and us, each restricted stock award shall immediately become free from all conditions or restrictions if, on or prior to the first anniversary of the date of the consummation of the change in control event, the participant’s employment with us or the acquiring or succeeding corporation is terminated for “good reason” by the participant or is terminated without “cause” by us or the acquiring or succeeding corporation.

Provisions Applicable to RSUs. Notwithstanding the provisions with respect to the treatment of the RSUs in a reorganization event, except to the extent specifically provided to the contrary in an award agreement or any other agreement between a participant and us, each RSU that vests solely based on continued service shall become immediately vested in full and free from forfeiture if, on or prior to the first anniversary of the date of the consummation of the change in control event, the participant’s employment with us or the acquiring or succeeding corporation is terminated for “good reason” by the participant or is terminated without “cause” by us or the acquiring or succeeding corporation.

Provisions Applicable to SARs and Other Stock-Based Awards. The Board may specify in an award at the time of the grant the effect of a change in control event on any SAR or other stock-based award.

Under the Amended 2022 Plan, “good reason” means the occurrence of any of the following without the participant’s prior written consent: (A) any change in the participant’s position, title or reporting relationship with us from and after such reorganization event or change in control event that diminishes in any material respect the authority, duties or responsibilities of the participant as in effect immediately preceding the reorganization event or change in control event, as the case may be; provided, however, that a change in the participant’s title or reporting relationship solely due to the us becoming a division, subsidiary or other similar part of a larger organization following a reorganization event or change in control event shall not by itself constitute “good reason”; or (B) any material reduction in the participant’s annual base compensation from and after such reorganization event or change in control event, as the case may be. Notwithstanding the foregoing, “good reason” shall not be deemed to have occurred unless (x) the participant provides us with written notice that the participant intends to terminate employment for one of the grounds set forth in subsections (A) or (B) within 60 days of such ground arising, (y) if such ground is capable of being cured, we have failed to cure such ground within a period of 30 days from the date of such written notice, and (z) the participant terminates employment within six months from the date that “good reason” first occurs.

Under the Amended 2022 Plan, “cause” means the occurrence of any of the following: (A) the participant’s willful failure to perform in any material respect the participant’s material duties or responsibilities for us, which is not cured within 30 days of written notice thereof to the participant from us; (B) repeated unexplained or unjustified absence from us inconsistent with the participant’s duties and responsibilities for us, which continues without explanation or justification after written notice thereof to the participant from us; (C) the participant’s willful misconduct that causes material and demonstrable monetary or reputational injury to us, including, but not limited to, misappropriation or conversion of our assets (other than non-material assets); or (D) the conviction of the participant of, or the entry of a plea of guilty or nolo contendere by the participant to, any crime involving moral turpitude or any felony.

Provisions for Foreign Participants

The Board has established, and may further establish, one or more sub-plans under the Amended 2022 Plan to satisfy applicable securities, tax or other laws of various jurisdictions. The Board has established, and may further establish, such sub-plans by adopting supplements to the Amended 2022 Plan containing any limitations on the Board’s discretion under the Amended 2022 Plan and any additional terms and conditions not otherwise inconsistent with the Amended 2022 Plan as the Board deems necessary or desirable. All supplements adopted by the Board are deemed to be part of the Amended 2022 Plan, but each supplement only applies to participants within the affected jurisdiction.

Withholding

The participant must satisfy all applicable federal, state, and local or other income and employment tax withholding obligations before we will deliver stock certificates or otherwise recognize ownership of common stock under an award. We may elect to satisfy the withholding obligations through additional withholding on salary or wages. If we elect not to or cannot withhold from other compensation, the participant must pay us the full amount, if any, required for withholding or have a broker tender to us cash equal to the withholding obligations. Payment of withholding obligations is due before we will issue any shares on exercise, vesting or release from forfeiture of an award or at the same time as payment of the exercise or purchase price, unless we determine otherwise. If provided for in an award or approved by the Board, a participant may satisfy the tax obligations in whole or in part by delivery (either by actual delivery or attestation) of shares of common stock, including shares retained from the award creating the tax obligation, valued at their fair market value. However, except as otherwise provided by the Board, that the total tax withholding where stock is being used to satisfy such tax obligations cannot exceed our minimum statutory withholding obligations (based on minimum statutory withholding rates for federal and state tax purposes, including payroll taxes, that are applicable to such supplemental taxable income), except that, to the extent that we are able to retain shares of common stock having a fair market value that exceeds the statutory minimum applicable withholding tax without financial accounting implications or we are withholding in a jurisdiction that does not have a statutory minimum withholding tax, we may retain such number of shares (up to the number of shares having a fair market value equal to the maximum individual statutory rate of tax) as we shall determine to be necessary to satisfy the tax liability associated with any award. Shares used to satisfy tax withholding requirements cannot be subject to any repurchase, forfeiture, unfulfilled vesting or other similar requirements.

Amendment or Termination

No award may be granted under the Amended 2022 Plan after May 18, 2032, but awards previously granted may extend beyond that date. Our Board may amend, suspend or terminate the Amended 2022 Plan or any portion of the Amended 2022 Plan at any time, except that (i) no amendment may be made to the plan to permit an option or SAR to be repriced without stockholder approval and (ii) no amendment that would require stockholder approval under the rules of the national securities exchange on which we maintain our primary listing may be made effective unless and until such amendment has been approved by our stockholders. If the national securities exchange on which we maintain our primary listing does not have rules regarding when stockholder approval of amendments to equity compensation plans is required (or if our common stock is not then listed on any national securities exchange), no amendment of the Amended 2022 Plan materially increasing the number of shares authorized under the plan (other than as provided under the Amended 2022 Plan with respect to certain corporate events or substitute awards), expanding the types of awards that may be granted under the plan or materially expanding the class of participants eligible to participate in the plan will be effective unless and until our stockholders approve such amendment. If at any time the approval of our stockholders is required as to any other modification or amendment under Section 422 of the Code or any successor provision with respect to incentive stock options, our Board may not effect such modification or amendment without such approval. Unless otherwise specified in the amendment, any amendment to the Amended 2022 Plan adopted in accordance with the procedures described above will apply to, and be binding on the holders of, all awards outstanding under the Amended 2022 Plan at the time the amendment is adopted, provided that our Board determines that such amendment, taking into account any related action, does not materially and adversely affect the rights of participants under the Amended 2022 Plan. No award will be made that is conditioned on stockholder approval of any amendment to the Amended 2022 Plan unless the award provides that (i) it will terminate or be forfeited if stockholder approval of such amendment is not obtained within no more than 12 months from the date the award was granted and (ii) it may not be exercised or settled (or otherwise result in the issuance of shares of our common stock) prior to the receipt of such stockholder approval.

If stockholders do not approve the Amendment, the Amendment will not go into effect, and we will not grant additional awards under the 2022 Plan in excess of the current share reserve. In this event, the Board will consider whether to adopt alternative arrangements based on its assessment of our needs.

Federal Income Tax Consequences

The following is a summary of the United States federal income tax consequences that generally will arise with respect to awards granted under the Amended 2022 Plan. This summary is based on the federal tax laws in effect as of the date of this proxy statement. In addition, this summary assumes that all awards are exempt from, or comply with, the rules

under Section 409A of the Code regarding non-qualified deferred compensation. Changes to these laws could alter the tax consequences described below.

Incentive Stock Options. A participant will not have income upon the grant of an incentive stock option. Also, except as described below, a participant will not have income upon exercise of an incentive stock option if the participant has been employed by the Company or its corporate parent or 50% or majority-owned corporate subsidiary at all times beginning with the option grant date and ending three months before the date the participant exercises the option. If the participant has not been so employed during that time, then the participant will be taxed as described below under “Non-statutory Stock Options.” The exercise of an incentive stock option may subject the participant to the alternative minimum tax.

A participant will have income upon the sale of the stock acquired under an incentive stock option at a profit (if sales proceeds exceed the exercise price). The type of income will depend on when the participant sells the stock. If a participant sells the stock more than two years after the option was granted and more than one year after the option was exercised, then all of the profit will be long-term capital gain. If a participant sells the stock prior to satisfying these waiting periods, then the participant will have engaged in a disqualifying disposition and a portion of the profit will be ordinary income and a portion may be capital gain. This capital gain will be long-term if the participant has held the stock for more than one year and otherwise will be short-term. If a participant sells the stock at a loss (sales proceeds are less than the exercise price), then the loss will be a capital loss. This capital loss will be long-term if the participant held the stock for more than one year and otherwise will be short-term.

Non-statutory Stock Options. A participant will not have income upon the grant of a non-statutory stock option. A participant will have compensation income upon the exercise of a non-statutory stock option equal to the value of the stock on the day the participant exercised the option less the exercise price. Upon sale of the stock, the participant will have capital gain or loss equal to the difference between the sales proceeds and the value of the stock on the day the option was exercised. This capital gain or loss will be long-term if the participant has held the stock for more than one year and otherwise will be short-term.

Stock Appreciation Rights. A participant will not have income upon the grant of a SAR. A participant generally will recognize compensation income upon the exercise of a SAR equal to the amount of the cash and the fair market value of any stock received. Upon the sale of the stock, the participant will have capital gain or loss equal to the difference between the sales proceeds and the value of the stock on the day the SAR was exercised. This capital gain or loss will be long-term if the participant held the stock for more than one year and otherwise will be short-term.

Restricted Stock Awards. A participant will not have income upon the grant of restricted stock (i.e. stock subject to a substantial risk of forfeiture) unless an election under Section 83(b) of the Code is made within 30 days of the date of grant. If a timely 83(b) election is made, then a participant will have compensation income equal to the value of the stock on the date of grant less the purchase price, if any. When the stock is sold, the participant will have capital gain or loss equal to the difference between the sales proceeds and the value of the stock on the date of grant. If the participant does not make an 83(b) election, then when the stock vests (i.e. stock subject to a substantial risk of forfeiture) the participant will have compensation income equal to the value of the stock on the vesting date less the purchase price, if any. When the stock is sold, the participant will have capital gain or loss equal to the sales proceeds less the value of the stock on the vesting date. Any capital gain or loss will be long-term if the participant held the stock for more than one year and otherwise will be short-term.

Restricted Stock Units. A participant will not have income upon the grant of an RSU. A participant is not permitted to make a Section 83(b) election with respect to an RSU award. When the shares or common stock are delivered with respect to the RSUs (which may be upon vesting or may be at a later date), the participant will have income on the date of delivery in an amount equal to the fair market value of the stock on such date less the purchase price, if any. When the stock is sold, the participant will have capital gain or loss equal to the sales proceeds less the value of the stock on the delivery date. Any capital gain or loss will be long-term if the participant held the stock for more than one year and otherwise will be short-term.

Other Stock-Based Awards. The tax consequences associated with any other stock-based award granted under the Amended 2022 Plan will vary depending on the specific terms of such award. Among the relevant factors are whether or

not the award has a readily ascertainable fair market value, whether or not the award is subject to forfeiture provisions or restrictions on transfer, the nature of the property to be received by the participant under the award, and the participant’s holding period and tax basis for the award or underlying common stock.

Tax Consequences to the Company. There will be no tax consequences to the Company except that the Company (or, if applicable, the affiliate employer) will be entitled to a deduction when a participant has compensation income, subject to the limitations of Section 162(m) of the Code.

THE BOARD UNANIMOUSLY RECOMMENDS THAT STOCKHOLDERS VOTE “FOR” THE APPROVAL OF THE AMENDMENT TO THE 2022 EQUITY INCENTIVE PLAN, AS AMENDED.

PROPOSAL 3:

APPROVAL OF AN AMENDMENT TO OUR AMENDED & RESTATED 2013 EMPLOYEE STOCK PURCHASE PLAN, AS AMENDED, TO INCREASE THE NUMBER OF SHARES OF OUR COMMON STOCK AVAILABLE FOR ISSUANCE THEREUNDER BY 1,400,000 SHARES

On February 5, 2026, upon the recommendation of our Compensation Committee, our Board approved the adoption, subject to stockholder approval, of an amendment (the “ESPP Amendment”) to the Company’s Amended & Restated 2013 Employee Stock Purchase Plan, as amended (the “Amended & Restated ESPP” and, as amended by the ESPP Amendment, the “Amended 2013 ESPP”), to increase the number of shares of common stock authorized for issuance under the Amended & Restated ESPP from 600,594 (as adjusted to reflect the Company’s 1-for-15 reverse stock split of our common stock effected on February 25, 2025) shares to 2,000,594 shares. No other amendments are being made to the Amended & Restated ESPP.

The Amended 2013 ESPP is intended to benefit the Company and our stockholders by attracting, retaining and motivating talented employees, which we believe to be critical for our success, and aligning the interests of participating employees with those of our stockholders. We believe that the ability to participate in the Amended 2013 ESPP is an attractive feature for current and potential employees by affording them the opportunity to share in the growth and success of the Company. The Amended 2013 ESPP also helps to attract and retain employees because employee stock purchase plans are commonly offered by our peers and other industry leaders. As of March 30, 2026, 165,461 shares remained available for future issuance under the Amended & Restated ESPP without giving effect to the approval of the ESPP Amendment. We estimate that, with an increase of 1,400,000 shares, we will have a sufficient number of shares of common stock to cover purchases under the Amended 2013 ESPP through approximately 2031, though the actual duration of the reserved shares will depend on participation and our stock price. Our Board believes it is in the best interests of the Company and our stockholders to continue to provide our employees with the opportunity to acquire an ownership interest in the Company through their participation in the Amended 2013 ESPP, encouraging them to remain in our employ and more closely aligning their interests with those of our stockholders. If the ESPP Amendment is not approved by our stockholders, our ability to recruit and retain employees could be negatively impacted if we do not have sufficient authorized shares available for future issuance under our Amended 2013 ESPP for our employees’ participation. To further encourage stock ownership among our employees while providing our employees with a benefit that is common in the companies with which we compete for talent, our Board has approved the ESPP Amendment. If the Company’s stockholders do not approve the ESPP Amendment, the proposed 1,400,000 additional shares will not become available for issuance under our Amended & Restated ESPP and we will not have sufficient shares to maintain our Amended & Restated ESPP after the current offering period. In such event, our Board will consider whether to adopt alternative arrangements based on its assessment of the Company’s compensation practices and the competitive markets in which the Company competes for talented employees.

Our Board urges stockholders to vote for this proposal as failure to obtain the required vote may limit the Company’s ability to attract, retain and motivate employees. If this proposal is approved by our stockholders, we intend to register the additional shares authorized for issuance under the Amended 2013 ESPP by filing a Registration Statement on Form S-8 as soon as practicable following such approval.

Description of the Amended 2013 ESPP

The following is a brief summary of the Amended 2013 ESPP. The following description is only a summary of the material terms of the Amended 2013 ESPP, and is qualified in its entirety by reference to the Amended & Restated ESPP, Amendment No. 1 and Amendment No. 2, a copy of each of which is attached to this proxy statement as Appendix B.

Eligibility

All employees of the Company and any subsidiary of the Company designated by our Board or Compensation Committee are eligible to participate in the Amended 2013 ESPP, provided that they work more than twenty (20) hours per week and for more than five (5) months in a calendar year, have been employed by the Company or a designated subsidiary for at least thirty (30) days prior to enrolling in the Amended 2013 ESPP and are employed by the Company or a designated subsidiary on the first day of the applicable offering period. No employee can be granted an option under the Amended 2013 ESPP that would result in the employee owning common stock and/or options to purchase common stock

representing five percent or more of the total combined voting power or value of all classes of our outstanding capital stock. As of March 30, 2026, approximately 219 employees (excluding NEOs and other executive officers), all three NEOs and three other executive officers who are not NEOs would have been eligible to participate in the Amended 2013 ESPP. Non-employee directors, consultants and advisors are not permitted to participate in the Amended 2013 ESPP.

Amended 2013 ESPP Operation

The Amended 2013 ESPP permits eligible employees to purchase shares of our common stock at a discount. Eligible employees may elect to participate by completing an enrollment form, timely filing it with our payroll office and authorizing after-tax payroll deductions from their pay. Employees can elect to contribute up to 15 percent (or such lower maximum contribution rate as our Board or Compensation Committee may, at its discretion, designate). Our Board or Compensation Committee may also, in its discretion, establish a different minimum payroll deduction percentage.

The Amended 2013 ESPP will be implemented by consecutive six (6) month offering periods. Our Board or Compensation Committee may, in its discretion, choose a different offering period of not more than twelve (12) months.

Offering periods will begin at such time as our Board may determine. On the first day of each offering period, each employee who is enrolled in the Amended 2013 ESPP will automatically receive an option to purchase, on the last trading day of the offering period, up to that number of shares of our common stock determined by multiplying $2,083 by the number of full months in the offering period and dividing the result by the closing price of our common stock on the first day of the offering period, or such lesser number of shares set by the Board or Compensation Committee.

However, no eligible employee may be granted an option under the Amended 2013 ESPP that permits the employee’s rights to purchase shares under the Amended 2013 ESPP to accrue at a rate that exceeds $25,000 in fair market value (determined at the date the option is granted) of our common stock in any given calendar year in which such option is outstanding at any time.

Unless an employee withdraws from the Amended 2013 ESPP, the employee’s option will be exercised automatically on the last trading day of the offering period as to the largest whole number of shares that are exercisable and can be purchased with the deductions accumulated as of the last trading day of the offering period.

Our Board or Compensation Committee will determine the purchase price of each of the shares purchased in a given offering period. The purchase price will be at least 85% of (i) the closing price of a share of our common stock on the first trading day of the offering period or the last trading day of the offering period, whichever is lower or (ii) the closing price of a share of our common stock on the last trading day of the offering period. In the absence of a determination by the Board or the Compensation Committee, the purchase price will be 85% of the lesser of the closing price of our common stock on the first trading day of the offering period or the last trading day of the offering period.

All payroll deductions received or held by the Company under the Amended 2013 ESPP may be used by us for any corporate purpose, and we will not be obligated to segregate such payroll deductions. No interest will accrue on the payroll deductions (except to the extent that our Board or Compensation Committee, in its sole discretion, elects to credit employee accounts with interest at a rate that it determines). An employee may decrease or discontinue the employee’s payroll deductions once during any offering period, by filing a new payroll deduction authorization form. However, an employee may not increase his or her payroll deduction during an offering period. Employees may purchase common stock under the Amended 2013 ESPP only through payroll deductions. An employee’s payroll deduction elections remain in effect for successive offering periods unless amended or terminated by the employee at the time and on the terms set forth in the Amended 2013 ESPP. In addition, an employee may elect to discontinue his or her payroll deductions during an offering period but not elect to withdraw his or her funds. In such cases, funds deducted prior to his or her election to discontinue shall be applied to the purchase of common stock on the last day of the offering period in which the funds were deducted. If an employee withdraws from participation during an offering period, the amounts contributed to the Amended 2013 ESPP will be refunded promptly without interest and the employee’s option granted for such offering period will automatically terminate. At the end of the offering period, the accumulated payroll contributions of each employee who continues to participate in the plan as of such date will be used to purchase shares of common stock (at the purchase price described above) subject to the limitations described above. An employee’s withdrawal from an offering period will not have any effect upon his or her eligibility to participate in succeeding offering periods or in any other

similar plan which the Company may adopt. If a participating employee’s employment ends before the last business day of an offering period, no payroll deduction will be taken from any pay then due and owing to the employee and the balance in the employee’s account will be paid to the employee.

The value of the common stock purchased will vary based on the fair market value of our common stock on the last day of the offering period. Accordingly, the dollar value and the number of shares that may be purchased in the future pursuant to the Amended 2013 ESPP are not currently determinable.

We are required to make equitable adjustments to the number and class of securities available under the Amended 2013 ESPP, the share limitations under the Amended 2013 ESPP and the purchase price for an offering period under the Amended 2013 ESPP to reflect stock splits, reverse stock splits, stock dividends, recapitalizations, combinations of shares, reclassifications of shares, spin-offs and other similar changes in capitalization or events or any dividends or distributions to holders of our common stock other than ordinary cash dividends.

In connection with a merger or other reorganization event (as defined in the Amended 2013 ESPP), our Board or a committee appointed by our Board may take any one or more of the following actions as to outstanding options to purchase shares of our common stock under the Amended 2013 ESPP on such terms as our Board or a committee determines:

Authorized Shares

Subject to adjustment, as described above, the maximum aggregate number of shares of our common stock authorized for issuance pursuant to the exercise of options granted under the Amended 2013 ESPP will be 2,000,594 shares. If the total number of shares of common stock with respect to which options are to be exercised at the end of an offering period exceeds the number of shares remaining available for issuance under the Amended 2013 ESPP, the Company will only issue to employees in that offering that number of shares remaining available for issuance, on a pro-rata basis.

Administration

The Amended 2013 ESPP will be administered by our Board or by a committee appointed by the Board. Our Board has appointed the Compensation Committee to administer the Amended 2013 ESPP. Our Board or the Compensation Committee has authority to make rules and regulations for the administration of the Amended 2013 ESPP, and its interpretation and decisions with respect to the Amended 2013 ESPP will be final and conclusive.

Our Board or Compensation Committee has the ability to change offering periods (including the commencement dates and length thereof) with respect to future offerings without stockholder approval. Our Board may terminate, suspend or amend the Amended 2013 ESPP at any time and for any reason, however if the approval of any amendment of the Amended 2013 ESPP by the stockholders is required in order for the plan to continue to satisfy the requirements of Section 423 of the Code, then such amendment will not be effective unless and until approved by the Company’s stockholders.

Our Board or Compensation Committee may allow employees who are citizens or residents of foreign jurisdictions to participate in an offering period or establish sub-plans for the benefit of such foreign employees to the extent such actions are in compliance with Section 423 of the Code.

Plan Benefits

Participation in the Amended 2013 ESPP is discretionary. The benefits received by any individual under the plan are dependent upon the individual’s decision to participate in the Amended 2013 ESPP, the amount that the individual decides to contribute to the Amended 2013 ESPP and the fair market value of the Company’s common stock on the exercise date. As a result, it is not possible to determine the benefits that will be received under the Amended 2013 ESPP by the Company’s NEOs, other executive officers and other employees. Non-employee directors, consultants and advisors are not eligible to participate in the Amended 2013 ESPP. On March 30, 2026, the last reported sale price of our common stock on the Nasdaq Global Select Market was $5.30.

The table below sets forth, for each of the individuals and groups indicated, the number of shares of our common stock purchased under the Amended & Restated ESPP since inception through March 30, 2026.

* Ineligible to participate in the Amended & Restated ESPP.

Federal Income Tax Consequences

The following generally summarizes the United States federal income tax consequences that will arise with respect to participation in the Amended 2013 ESPP and with respect to the sale of common stock acquired under the plan. This summary is based on the tax laws in effect as of the date of this proxy statement. The Amended 2013 ESPP is intended to qualify as an “employee stock purchase plan” as defined in Section 423 of the Code. This summary assumes that the Amended 2013 ESPP complies with Section 423 of the Code. Further, this summary assumes that the purchase price for shares is 85% of the closing price of a share of our common stock on the first day of the offering period or the last day of the offering period, whichever is lower. Changes to these laws could alter the tax consequences described below.

Tax Consequences to Participants

A participant will not have income upon enrolling in the Amended 2013 ESPP or upon purchasing stock at the end of a purchase period. A participant may have both compensation income and a capital gain or loss upon the sale of stock that was acquired under the Amended 2013 ESPP. The amount of each type of income and loss will depend on whether the participant disposes of the stock in a qualifying or disqualifying disposition. A qualifying disposition is when the participant sells the stock more than two years after the commencement of the offering during which the stock was purchased and more than one year after the date on which the participant purchased the stock at a profit (i.e., the sales proceeds exceed the purchase price). In a qualifying disposition, the participant will have compensation income equal to the lesser of:

Any profit in excess of compensation income will be long-term capital gain. If the participant sells the stock at a loss (i.e., if sales proceeds are less than the purchase price) after satisfying these waiting periods, then the loss will be a long-term capital loss.

If the participant sells the stock prior to satisfying these waiting periods, then he or she will have engaged in a disqualifying disposition. Upon a disqualifying disposition, the participant will have compensation income equal to the value of the stock on the day he or she purchased the stock less the purchase price. The participant also will have a capital gain or loss equal to the difference between the sales proceeds and the value of the stock on the day he or she purchased the stock. This capital gain or loss will be long-term if the participant has held the stock for more than one year and short-term if held one year or less.

Tax Consequences to Us

There will be no tax consequences to us except that we will be entitled to a deduction when a participant recognizes compensation income upon a disqualifying disposition. Any such deduction will be subject to the limitations of Section 162(m) of the Code.

The Board Unanimously Recommends that Stockholders Vote “FOR” the Approval of the Amendment TO OUR AMENDED & RESTATED 2013 employee stock purchase plan, AS AMENDED.

PROPOSAL 4:

ADVISORY VOTE ON THE COMPENSATION OF OUR NAMED EXECUTIVE OFFICERS

We are providing our stockholders the opportunity to vote to approve, on an advisory basis, the compensation of our NEOs as disclosed in this proxy statement in accordance with the SEC’s rules. This proposal, which is commonly referred to as “say-on-pay,” is required by the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010, which added Section 14A to the Exchange Act. Currently, a say-on-pay vote is submitted to our stockholders every year.

We encourage our stockholders to closely read the “Executive Compensation” section of this proxy statement, which describes in detail our executive compensation programs and the decisions made by our Compensation Committee and our Board with respect to the year ended December 31, 2025.

As we describe in detail in the “Executive Compensation - Overview,” section of this proxy statement, we maintain straightforward executive compensation programs that consist almost entirely of base salary, an annual cash incentive bonus and annual equity awards. These elements of compensation have been selected by our Compensation Committee because the committee believes that they effectively achieve the fundamental goals of our compensation program, which are to attract, motivate and retain qualified and talented executives who are critical to our success, motivating them to achieve our business goals and rewarding them for superior short- and long-term performance. One of the goals of our Compensation Committee is to ensure that our compensation programs are aligned with the interests of our stockholders and our business goals in order to attain our ultimate objective of increasing stockholder value. We believe that, consistent with these goals, the total compensation paid to each of our NEOs is fair, reasonable and competitive. Further, we believe our programs do not encourage excessive risk-taking by management.

We do not provide any compensation or benefit plans to executive officers that are not also available to other employees. We differentiate among executive officers primarily based on size of annual cash incentive awards and annual equity awards and, to a lesser extent, base salary.

Our Board is asking stockholders to approve, on an advisory basis, the following resolution:

RESOLVED, that the compensation paid to Karyopharm Therapeutics Inc.’s NEOs, as disclosed pursuant to the compensation disclosure rules of the SEC, including the compensation tables and any related material disclosed in this proxy statement, is hereby approved.

As an advisory vote, this proposal is not binding. The outcome of this advisory vote does not overrule any decision by the Company or the Board (or any committee thereof), create or imply any change to the fiduciary duties of the Company or the Board (or any committee thereof), or create or imply any additional fiduciary duties for the Company or the Board (or any committee thereof). However, our Compensation Committee and Board value the opinions expressed by our stockholders in their vote on this proposal and will consider the outcome of the vote when making future compensation decisions for NEOs.

THE BOARD UNANIMOUSLY RECOMMENDS THAT STOCKHOLDERS VOTE “FOR” THE APPROVAL OF THE COMPENSATION OF OUR NAMED EXECUTIVE OFFICERS.

EXECUTIVE COMPENSATION

This section discusses the material elements of our executive compensation policies and decisions and important factors relevant to an analysis of these policies and decisions. It provides qualitative information regarding the manner and context in which compensation is awarded to and earned by our NEOs and is intended to place in perspective the information presented in the following tables and the corresponding narrative.

Our NEOs for the fiscal year ended on December 31, 2025 are:

Overview

Our Company

We are a commercial-stage pharmaceutical company whose dedication to pioneering novel cancer therapies is fueled by a belief in the extraordinary strength and courage of patients with cancer. We discover, develop and commercialize novel, life-changing cancer therapies in disease areas with high unmet need. Our primary focus is on marketing XPOVIO in its currently approved indications as well as developing and seeking regulatory approval of selinexor as an oral agent targeting multiple high unmet need cancer indications, including our lead clinical programs in myelofibrosis and endometrial cancer and our other late-stage clinical program in multiple myeloma.

2025 Executive Compensation Overview

Our executive compensation program is designed to attract and retain top talent, reward strong performance, and align incentives with the creation of long-term stockholder value, while also considering the Company’s cash and equity resource constraints.

During 2025, we navigated significant challenges, including:

Notwithstanding these challenges, we continued to successfully operate our business and execute on our strategic priorities, including:

2025 Compensation Decision-Making Framework

In light of these circumstances and our achievements, 2025 executive compensation decisions were made with a heightened focus on three core objectives: retention of critical leadership; alignment with stockholder interests; and prudent cash and equity management. The Compensation Committee and the Board took the following actions with respect to 2025 compensation of our NEOs:

As a result of the foregoing, the 2025 executive compensation program deviated from our historical compensation practices in the following respects:

Stockholder Feedback

In its compensation review process, the Compensation Committee considers whether our executive compensation and benefits program serves the interests of our stockholders. The Compensation Committee values ongoing, constructive feedback from our stockholders on compensation, and members of senior management regularly engage with stockholders and report this stockholder feedback to the Compensation Committee. The Compensation Committee will continue to monitor our executive compensation program and engage with our stockholders and take into account stockholder input.

Executive Compensation Program Best Practices

Our Compensation Committee believes that a strong foundation for our compensation program is necessary to execute our executive compensation philosophy effectively. The following best practices served as the foundation for our 2025 executive compensation program:

Compensation Philosophy

The objective of our executive compensation program is to align management interests with the drivers of value creation for our stockholders and support the achievement of our strategic goals and objectives. We are committed to our compensation philosophy, which has historically incorporated the following principles:

Our Compensation Committee is responsible for overseeing the total compensation of our senior management team, which is comprised of our executive officers and certain other senior managers. In this capacity, our Compensation Committee designs, implements, reviews and approves all compensation for our executive officers, except that in the case of our President and Chief Executive Officer, the Board approves all compensation-related matters based on the review and recommendation of our Compensation Committee.

We develop our compensation programs after reviewing publicly available compensation data and subscription survey data for our compensation peer group, provided by our Compensation Committee’s compensation consultant. For setting 2025 compensation, our Compensation Committee engaged Alpine, an independent consulting firm, to advise on executive compensation matters including: executive compensation philosophy, overall compensation program design, compensation peer group development and updates, and competitive data for executive officer and director compensation programs. In August 2025, the Compensation Committee engaged WTW, an independent consulting firm, to advise on executive compensation matters beginning in September 2025, including the 2025 Retention Program.

Our Compensation Committee assessed the independence of each of Alpine and WTW consistent with the applicable Nasdaq Listing Rules and SEC rules and concluded that the engagement of each of Alpine and WTW did not raise any conflicts of interest. We paid the cost for Alpine and WTW’s services; however, our Compensation Committee retained the sole authority to direct, terminate, or engage Alpine and WTW services, and Alpine and WTW reported directly to our Compensation Committee.

Defining and Comparing Compensation to Competitive Market Data

In evaluating the target total direct compensation opportunities of our NEOs, in September 2024, our Compensation Committee, with input from senior management and Alpine, established a compensation peer group comprised of 18 companies selected primarily on the basis of the following criteria:

We believe that the compensation practices of our 2025 peer group provided us with appropriate compensation market comparisons for evaluating the 2025 compensation for our NEOs. We strive to ensure that the total compensation levels for our executives are competitive with peer companies so that we can attract and retain high-performing key executive talent. Notwithstanding the similarities of the 2025 compensation peer group to our Company, due to the nature of our business, we compete for executive talent with larger public companies across our industry that are more established than we are or that possess greater resources than we do, and with smaller private companies that may be able to offer greater equity compensation potential. Therefore, in evaluating the compensation of our executive officers, the Compensation Committee uses the companies in our compensation peer group primarily as reference points to understand market practices among our peers and then assesses each individual executive’s compensation taking into consideration a number of subjective measures, such as individual and Company performance levels, contributions to the execution of our short-term goals and long-term strategy, uniqueness of skillsets, demonstration of executive leadership, demand for

particular talent and internal parity.

Elements of Executive Compensation and Pay for Performance Alignment

We believe our executive compensation program is effectively designed to implement a pay for performance culture that aligns with the interests of our stockholders and our compensation philosophy as well as serves to enable us to attract, retain and motivate a strong, capable leadership team, which is essential to the execution of our strategic objectives. The three primary elements of our executive compensation program include:

* Excludes the cash retention payments described above awarded to Mr. Poulton and Dr. Rangwala pursuant to the 2025 Retention Program.

In addition, our executive compensation program includes health and welfare benefits, other employee benefits and severance and change in control payments and benefits.

Base Salaries

We provide annual base salaries to our NEOs to compensate them with a fair and competitive base level of compensation for services rendered during the year. Base salaries for our NEOs typically are established through arm’s-length negotiation at the time the executive is hired, taking into account responsibilities, experience, internal parity and competitive market data. On an annual basis, our Compensation Committee reviews and evaluates, with input from our President and Chief Executive Officer for executives other than himself, the need for adjustment of the base salaries of our NEOs. When making this evaluation, our Compensation Committee considers compensation peer group data, market competitiveness, expected future contribution, and changes and expected changes in the NEO’s responsibilities. Our Compensation Committee also considers individual performance, promotions, market data, industry trends, and the executive’s role in the company’s growth, as well as the difficulty of replacement in a competitive talent market. We do

not provide for any formulaic base salary increases for our NEOs and none of our executive officers is currently party to an employment agreement that provides for automatic or scheduled increases in base salary.

In January 2025, in connection with its annual review of executive compensation matters, our Compensation Committee determined that our NEOs and certain other executives would not receive an increase in their base salary in connection with the 2025 annual performance review period based primarily on a desire to preserve cash for the business and overall competitive positioning against our peer group.

The 2024 and 2025 base salaries of our NEOs were as follows:

Annual Performance-Based Cash Incentive Compensation

Our Compensation Committee establishes an appropriate mix of cash payments and equity incentive awards to achieve our short-term and long-term compensation objectives. Annual performance-based cash incentive awards are typically paid to our employees, including our executive officers, under the Annual Bonus Plan. The Annual Bonus Plan is designed to attract, motivate, and retain employees by promoting and rewarding the achievement of key short-term corporate goals and objectives and other value-driving accomplishments as well as individual performance, while aligning the interests of employees and stockholders.

Our corporate goals and objectives applicable to our annual performance-based cash incentive awards are established early in the year and are designed to be challenging and aligned with our strategic priorities. These corporate goals typically include objectives related to the advancement of our development programs, commercialization activities, and corporate and financial performance, which we believe will create stockholder value.

During the course of the year, additional value-creating milestones may be achieved that merit recognition. Although our Board does not adjust corporate goals during the course of a year, it retains the flexibility to recognize significant value-creating achievements that were not anticipated or reflected in the corporate goals established at the start of the year through our annual bonus program.

The target annual bonus opportunity for our executive officers is determined based on the executive officer’s position as described in the Annual Bonus Plan, with a maximum payout capped at 200% of the executive officer’s target bonus amount. Prior to the beginning of each fiscal year, the Compensation Committee also determines the weighting allocation applicable to bonuses to be paid to our executive officers, other than our President and Chief Executive Officer, for that fiscal year.

For 2025, as part of the 2025 Retention Program, in lieu of a payment under the terms of the Annual Bonus Plan, bonus awards that would otherwise have been paid in early 2026 to all employees, including our NEOs, were paid 50% in October 2025, with the remaining 50% to be paid in April 2026. Payment of each installment is subject to continued service through the applicable payment date and repayment in the event of certain terminations of employment prior to March 31, 2026 and July 31, 2026, respectively. The payout for the 2025 annual bonuses was 90% of each employee’s 2025 annual bonus target amount, with approximately 20% of target awarded based on retention and approximately 70% of target awarded based on the then expected 2025 corporate performance.

The following table presents the 2025 annual cash bonuses for each of our NEOs, as approved by the Board, based on the modification to the Annual Bonus Plan, described above:

Cash Bonuses Under the 2025 Retention Program

As part of the 2025 Retention Program, described above, Mr. Poulton and Dr. Rangwala received the following cash retention bonuses in October 2025 in recognition of the critical importance of their roles in the execution of our near-term clinical development and regulatory milestones related to our myelofibrosis and endometrial cancer trials:

Long-Term Equity Incentive Compensation

We use our equity incentive program to motivate our executives and employees to deliver long-term Company performance, align participant and stockholder interests and promote retention. The market for qualified and talented executives in the biopharmaceutical industry is highly competitive and we compete for talent with many companies that have greater resources than we do. Accordingly, we believe equity compensation is a crucial component of any competitive executive compensation package we offer.

Equity awards granted to our executive officers are approved by our Compensation Committee or the Board, with any equity awards granted to our President and Chief Executive Officer approved by the Board. Annual equity awards are generally granted at the beginning of each year and awards may vary among our executive officers based on their positions and annual performance assessments. In addition, our Compensation Committee reviews all elements of the executive’s compensation to evaluate whether his or her target total direct compensation opportunity is aligned with our overall philosophy and objectives.

We believe RSU awards serve to align the interests of our NEOs with our stockholders given that the value of these awards ultimately realized is directly tied to our stock price performance and that the time-based vesting feature of these awards promotes retention by incentivizing our NEOs to remain in our employment during the vesting period.

All stock options granted to our executives have exercise prices equal to the fair market value of our common stock on the date of grant, so that the recipient will not earn any compensation from his or her options unless our share price increases above the exercise price on the date of grant. Accordingly, this portion of our executive officers’ compensation is at risk and is directly aligned with stockholder value creation.

The equity awards granted to our executives generally vest over three or four years. Typically, the stock options we grant to our executives have a ten-year term and vest one-fourth on the first anniversary of the grant date and then monthly thereafter until the fourth anniversary of such date and one-third of the RSU awards vest on each of three

anniversaries of the grant date. From time to time, we grant equity awards with vesting terms that differ from our standard vesting provisions, such as the October 2025 retention equity awards discussed below. Vesting of equity awards to employees generally ceases upon termination of a business relationship with the Company and exercise rights for stock options typically cease three months following termination of a business relationship with the Company, except in the case of death or disability.

Annual Equity Awards

In January 2025, our Compensation Committee approved annual equity awards for Mr. Poulton and Dr. Rangwala consisting of (i) stock options to purchase 10,000 and 10,833 shares of our common stock, respectively and (ii) stock-settled RSUs with respect to 5,000 and 5,416 shares of our common stock, respectively. In addition, the Compensation Committee recommended to the Board, and the Board approved, the annual equity awards for Mr. Paulson consisting of stock options to purchase 40,000 shares of our common stock and stock-settled RSUs with respect to 20,000 shares of our common stock. The exercise price of the stock options granted to each of Mr. Poulton, Dr. Rangwala and Mr. Paulson for their respective annual equity award was $7.95, which is equal to the closing price per share of our common stock on the Nasdaq Global Select Market on February 28, 2025 (the “Grant Date”). These stock option awards vest as to 25% of the shares on the first anniversary of the Grant Date and then monthly thereafter until the fourth anniversary of such date and the RSUs vest in equal annual installments over a three-year period beginning on the first anniversary of the Grant Date.

Retention Awards

From time to time, we may grant retention awards if our Compensation Committee or Board determine such awards are appropriate in order to motivate, retain and incentivize our executives through critical milestones.

In January 2025, our Compensation Committee awarded retention grants, effective as of February 28, 2025, to certain of our executive officers, including Mr. Poulton and Dr. Rangwala. Accordingly, each of Mr. Poulton and Dr. Rangwala was granted a stock option to purchase 9,166 shares at an exercise price of $7.95, which was equal to the closing price per share of our common stock on the Nasdaq Global Select Market on the Grant Date. This award will vest as to one-fourth of the shares on the first anniversary of the Grant Date and then monthly thereafter until the fourth anniversary of such date. In addition, each of Mr. Poulton and Dr. Rangwala was granted a stock-settled RSU award with respect to 4,583 shares of our common stock, that will vest in equal annual installments over a two-year period beginning on the first anniversary of the Grant Date.

In October 2025, as part of the 2025 Retention Program, our Board awarded RSU grants, effective as of October 15, 2025, to certain of our executive officers, including Messrs. Paulson and Poulton. Accordingly, Mr. Paulson and Mr. Poulton were granted RSU awards for 114,285 and 39,682 shares of our common stock, respectively, that will vest in full on December 31, 2026.

The following table sets forth the total grant date fair market value of the equity awards granted to each of our NEOs in 2025, as described above:

PSU Milestones Achieved

In 2023, in an effort to improve the linkage between pay and performance and better align the interests of our executive officers and stockholders, our Compensation Committee introduced PSU awards as a component of the mix of equity awards granted to our executive officers. The PSU awards granted in February 2023 vest over a multi-year period upon the achievement of certain objectives comprising three equally weighted performance metrics related to (i) strategic

revenue, (ii) clinical development milestones, and (iii) relative TSR over a span of one to four years. In September 2025, our Compensation Committee determined that, based on the complete enrollment in our Phase 3 myelofibrosis clinical trial, the second objective of the clinical development milestone metric under the 2023 PSUs was achieved, which resulted in the vesting of 16.67% of the target PSUs allocated to such metric and the PSU shares vested as of September 12, 2025. Based on the Company’s revenue and TSR performance through December 31, 2025, no portion of the PSUs with respect to such metrics vested as of such date. The table below sets forth the number of 2023 PSUs that vested for each NEO in 2025, each of which resulted from the achievement of the second objective of the clinical development milestone metric.

Benefits and Other Compensation

Health and Welfare Benefits

Our NEOs are eligible to participate in all of our employee benefit plans, including our medical, dental, vision, group life and disability insurance plans, on the same terms as non-executive officer employees. We believe that these health and welfare benefits help ensure that we have a productive and focused workforce through reliable and competitive health and other benefits. Currently, we do not view perquisites or other personal benefits as a significant component of our executive compensation program.

Retirement Savings Plan

We maintain a 401(k) retirement savings plan (the “401(k) Plan”) that is intended to be a tax-qualified defined contribution plan under the Code. In general, all of our U.S.-based employees aged 18 or older are eligible to participate in the Section 401(k) Plan upon commencement of their employment.

The 401(k) Plan includes a salary deferral arrangement pursuant to which participants may elect to reduce their current compensation by up to the statutorily prescribed limit, equal to $23,500 in 2025 (an additional $7,500 in catch-up contributions is permitted for participants aged 50 to 59 and 64 and over, while participants aged 60 to 63 were permitted to make catch-up contributions of up to $11,250). We also match employee contributions to our 401(k) Plan, up to a maximum of 4% of an employee’s cash compensation during each pay period.

Severance and Change in Control Payments and Benefits

Under our employment arrangements with our NEOs, we have agreed to provide severance payments and other benefits in the event of the termination of their employment under specified circumstances. We have provided more detailed information about these payments and benefits, under the caption “Executive Compensation - Employment, Severance and Change in Control Arrangements” below.

We believe providing severance and/or change in control payments and benefits as an element of our compensation structure can help us compete for executive talent and attract and retain highly talented executive officers whose contributions are critical to our long-term success. Further, we prefer to have certainty regarding the potential severance amounts payable to our NEOs, rather than negotiating severance at the time that a NEO’s employment terminates. We believe that providing severance and change in control benefits will offer sufficient cash continuity protection such that our executives will focus their full time and attention on the requirements of the business rather than the potential implications for their respective position in the event of a change in control. After consultation with our compensation consultant, we believe that our severance and change in control payments and benefits are appropriate.

We do not offer defined benefit pension plans or non-qualified deferred compensation plans to our employees, including our executive officers.

Insider Trading Policies and Practices

Insider Trading Policy

We have adopted an Insider Trading Policy governing the purchase, sale and/or other dispositions of Company securities by our directors, officers, employees, designated consultants and other covered persons. We believe our Insider Trading Policy is reasonably designed to promote compliance with insider trading laws, rules and regulations, and Nasdaq listing standards. A copy of our Insider Trading Policy is filed as Exhibit 19.1 to our 2025 Annual Report.

Our Insider Trading Policy prohibits those individuals and their related persons from engaging in any speculative transactions involving our common stock, including the following activities: short sales of our securities, including short sales “against the box”; purchases or sales of puts, calls or other derivative securities based on our securities; standing orders with brokers other than under an approved trading plan, purchases of financial instruments (including prepaid variable forward contracts, equity swaps, collars and exchange funds) that are designed to hedge or offset any decrease in the market value of our securities; the purchase of our securities on margin; borrowing against our securities held in a margin account; or pledging our securities as collateral for a loan. However, an exception may be granted where an employee or non-employee director wishes to pledge our securities as collateral for a loan (other than a margin loan) and clearly demonstrates the financial capacity to repay the loan without resort to the pledged securities. Any person who wishes to pledge our securities as collateral for a loan must submit a request for approval to our principal financial officer. In addition, any such request by a director or executive officer must also be reviewed and approved by the Audit Committee.

Compensation Recovery (“Clawback”) Policy

Effective October 2, 2023, the Board adopted a compensation recovery (clawback) policy, which provides that, in the event we are required to prepare an accounting restatement due to our material non-compliance with any financial reporting requirement under the U.S. federal securities laws as required by the Dodd-Frank Act and corresponding Nasdaq listing standards, we will attempt to recover any incentive-based compensation received by any current or former executive officer during the three completed fiscal years immediately preceding the date on which we are required to prepare the restatement that is in excess of what otherwise would have been received by such executive officer had the amount of incentive-based compensation been determined based on the restated amounts. A copy of our compensation recovery policy is filed as Exhibit 97 to our 2025 Annual Report.

2025 Summary Compensation Table

The following table sets forth information regarding compensation earned by each of our NEOs during the years ended December 31, 2025 and, to the extent required by SEC disclosure rules, December 31, 2024.