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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.          )

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PRELIMINARY PROXY STATEMENT SUBJECT TO COMPLETION DATED AUGUST 5, 2015

Dear Stockholders:

         You are cordially invited to attend a special meeting of the stockholders of KYTHERA Biopharmaceuticals, Inc. ("KYTHERA") to be held on [    ·    ], 2015 at [    ·    ] local time, at [    ·    ] (the "special meeting").

         As previously announced, on June 17, 2015, Allergan plc ("Allergan") entered into an Agreement and Plan of Merger ( the "Initial Merger Agreement") with KYTHERA and Keto Merger Sub, Inc., an indirect wholly owned subsidiary of Allergan ("Merger Sub"), as amended by Amendment No. 1, dated as of July 1, 2015 ("Amendment No. 1"), providing for the merger of Merger Sub with and into KYTHERA (the "Merger"), with KYTHERA surviving the merger as an indirect wholly owned subsidiary of Allergan. The Initial Merger Agreement, as amended by Amendment No. 1, was subsequently amended and restated by Allergan, KYTHERA and Merger Sub on August 4, 2015 (such amended and restated agreement, as it may be further amended from time to time, the "Amended and Restated Merger Agreement"). Following the Merger, KYTHERA common stock will be delisted from The NASDAQ Global Select Market ("NASDAQ"), deregistered under the Securities Exchange Act of 1934, as amended, and cease to be publicly traded. The acquisition of KYTHERA will be effected under Delaware law.

         As a result of the Merger, each share of KYTHERA common stock issued and outstanding immediately prior to the Merger (other than shares held by stockholders who properly demand their appraisal rights under Delaware law and shares held by KYTHERA as treasury stock or owned by Allergan, Merger Sub or any of their respective subsidiaries, which will be canceled without consideration, and shares subject to any unvested KYTHERA restricted stock award which is to be assumed by Allergan) will be converted into the right to receive $75.00 in cash, without interest. For a description of the consideration that KYTHERA stockholders will receive, see the section entitled "The Amended and Restated Merger Agreement—Consideration to KYTHERA Stockholders" beginning on page 83 of the accompanying proxy statement.

         KYTHERA is holding a special meeting to vote on the adoption of the Amended and Restated Merger Agreement and related matters. KYTHERA and Allergan cannot complete the proposed Merger unless, among other things, KYTHERA stockholders vote to adopt the Amended and Restated Merger Agreement.

         Your vote is very important. A failure to vote will have the same effect as a vote "AGAINST" the adoption of the Amended and Restated Merger Agreement. To ensure your representation at the special meeting, please complete and return the enclosed proxy card or submit your proxy by telephone or through the Internet. Please submit your proxy promptly whether or not you expect to attend the special meeting. Submitting a proxy now will not prevent you from being able to vote in person at the special meeting.

         The KYTHERA board of directors has determined that the Amended and Restated Merger Agreement and the transactions contemplated thereby, including the Merger, are advisable, fair to, and in the best interests of KYTHERA and the KYTHERA stockholders, has approved and declared advisable the Amended and Restated Merger Agreement and the transactions contemplated thereby, including the Merger, on the terms and subject to the conditions set forth therein, and recommends that KYTHERA's stockholders vote "FOR" the adoption of the Amended and Restated Merger Agreement.

         The obligations of KYTHERA and Allergan to complete the Merger are subject to the satisfaction or waiver of a number of conditions set forth in the Amended and Restated Merger Agreement, a copy of which is included as Annex A to the proxy statement. The proxy statement provides you with detailed information about the proposed Merger. It also contains or references information about KYTHERA and certain related matters.

         You are encouraged to read this document carefully. On behalf of the KYTHERA board of directors, thank you for your consideration and continued support.

         Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the Merger or passed upon the adequacy or accuracy of the disclosure in this document. Any representation to the contrary is a criminal offense.

         The date of this proxy statement is [    ·    ], and it is first being mailed to stockholders of KYTHERA on or about [    ·    ].

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KYTHERA BIOPHARMACEUTICALS, INC.
30930 RUSSELL RANCH ROAD, 3RD FLOOR
WESTLAKE VILLAGE, CA 91362

NOTICE OF A SPECIAL MEETING OF STOCKHOLDERS
TO BE HELD ON [    ·    ], 2015

        NOTICE IS HEREBY GIVEN that a special meeting (the "special meeting") of the stockholders of KYTHERA Biopharmaceuticals, Inc. ("KYTHERA") will be held at [    ·    ] at [    ·    ] (local time) on [    ·    ], 2015 for the following purposes:

1.

to adopt the Amended and Restated Agreement and Plan of Merger, dated as of August 4, 2015 (as it may be further amended from time to time, the "Amended and Restated Merger Agreement"), by and among Allergan plc ("Allergan"), Keto Merger Sub, Inc. and KYTHERA (the "Merger Proposal");



2.

to approve the adjournment of the special meeting to another date and place if necessary or appropriate to solicit additional votes in favor of the Merger Proposal (the "Adjournment Proposal"); and



3.

to approve, on a non-binding, advisory basis, the compensation to be paid to KYTHERA's named executive officers that is based on or otherwise relates to the Merger (the "Merger-Related Named Executive Officer Compensation Proposal"), as disclosed pursuant to Item 402(t) of Regulation S-K in "The Merger—Interests of KYTHERA's Directors and Executive Officers in the Merger—Quantification of Payments and Benefits to KYTHERA's Named Executive Officers" beginning on page 78 of the accompanying proxy statement.

        The approval by KYTHERA stockholders of the Merger Proposal is required to complete the merger (the "Merger") described in the accompanying proxy statement.

        KYTHERA will transact no other business at the special meeting, except for business properly brought before the special meeting or any adjournment or postponement thereof.

        The Merger Proposal is described in more detail in the accompanying proxy statement, which you should read carefully in its entirety before you vote. A copy of the Amended and Restated Merger Agreement is attached as Annex A to the accompanying proxy statement.

        The KYTHERA board of directors has set [    ·    ], 2015 as the record date for the special meeting. Only holders of record of shares of KYTHERA common stock at the close of business on [    ·    ], 2015 will be entitled to notice of and to vote at the special meeting and any adjournments thereof. Any stockholder entitled to attend and vote at the special meeting is entitled to appoint a proxy to attend and vote on such stockholder's behalf. Such proxy need not be a holder of shares of KYTHERA common stock.

        Your vote is very important. To ensure your representation at the special meeting, please complete and return the enclosed proxy card or submit your proxy by telephone or through the Internet. Please submit your proxy promptly whether or not you expect to attend the special meeting. Submitting a proxy now will not prevent you from being able to vote in person at the special meeting.

        The KYTHERA board of directors has approved and declared advisable the Amended and Restated Merger Agreement and recommends that you vote "FOR" the Merger Proposal, "FOR" the Adjournment Proposal and "FOR" the Merger-Related Named Executive Officer Compensation Proposal.

Westlake Village, California
[    ·    ], 2015

PLEASE SUBMIT A PROXY FOR YOUR SHARES OF KYTHERA COMMON STOCK PROMPTLY. YOU CAN FIND INSTRUCTIONS FOR DOING SO ON THE ENCLOSED PROXY CARD. IF YOU HAVE QUESTIONS ABOUT THE PROPOSALS OR ABOUT VOTING YOUR SHARES, PLEASE CALL (800) 322-2885 (TOLL-FREE) OR (212) 929-5500 (COLLECT).

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ADDITIONAL INFORMATION

        The accompanying proxy statement incorporates by reference important business and financial information about KYTHERA from documents that are not included in or delivered with the accompanying proxy statement. This information is available without charge to you upon written or oral request. You can obtain the documents incorporated by reference in the proxy statement by requesting them in writing, by email or by telephone from KYTHERA at the addresses and telephone numbers listed below or by accessing the website listed below. The information provided on the website listed below is not a part of the accompanying proxy statement and therefore is not incorporated by reference into the accompanying proxy statement.

KYTHERA Biopharmaceuticals, Inc.
30930 Russell Ranch Road, 3rd floor
Westlake Village, CA 91362
Attention: Investor Relations
Telephone: (818) 587-4500
Email: ir@kythera.com
investors.kythera.com/index.cfm

        In addition, if you have questions about the Merger or the KYTHERA special meeting, or if you need to obtain copies of the accompanying proxy statement, proxy card or other documents incorporated by reference in the accompanying proxy statement, you may contact the KYTHERA proxy solicitation agent at the address and telephone number listed below. You will not be charged for any of the documents you request.

MacKenzie Partners Inc.
105 Madison Avenue
New York, NY 10016
Telephone: (212) 929-5500 (call collect)
or
Toll-Free (800) 322-2885

To obtain timely delivery of these documents before the KYTHERA special meeting, you must request
the information no later than [    ·    ], 2015.

        For a more detailed description of the information incorporated by reference in the accompanying proxy statement and how you may obtain it, see the section entitled "Where You Can Find More Information" beginning on page 127 of the accompanying proxy statement.

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QUESTIONS AND ANSWERS ABOUT THE MERGER AND THE SPECIAL MEETING

        The following are answers to certain questions you may have regarding the Merger and the special meeting of the stockholders of KYTHERA to be held on [    ·    ], 2015 at [    ·    ] local time, at [    ·    ] (referred to in this proxy statement as the "KYTHERA special meeting"). You are urged to read carefully this entire proxy statement, because the information in this section may not provide all of the information that might be important to you in determining how to vote. Additional important information is also contained in the Annexes to, and the documents incorporated by reference into, this proxy statement. See the section entitled "Where You Can Find More Information" beginning on page 127 of this proxy statement. All references in this proxy statement to "Allergan" refer to Allergan plc, an Irish public limited company; all references to "Merger Sub" refer to Keto Merger Sub, Inc., a Delaware corporation and an indirect wholly owned subsidiary of Allergan; all references to "KYTHERA", "we" or "our" refer to KYTHERA Biopharmaceuticals, Inc., a Delaware corporation; all references to the "Initial Merger Agreement" refer to the Agreement and Plan of Merger, dated as of June 17, 2015, by and among Allergan, Merger Sub and KYTHERA; all references to "Amendment No. 1" refer to Amendment No. 1 to the Initial Merger Agreement, dated as of July 1, 2015, by and among Allergan, Merger Sub and KYTHERA and all references to the "Initial Merger Agreement, as amended by Amendment No. 1" refer to the Initial Merger Agreement, as amended by Amendment No. 1. All references to the "Amended and Restated Merger Agreement" refer to the Amended and Restated Agreement and Plan of Merger, dated as of August 4, 2015, by and among Allergan, Merger Sub and KYTHERA as it may be further amended from time to time, a copy of which is included as Annex A to this proxy statement; all references to the "Amended and Restated Voting Agreement" refer to the Amended and Restated Stockholder Voting Agreement, dated as of August 4, 2015, by and between Allergan and each of the individuals or entities listed on the signature pages thereto, as it may be amended from time to time, a copy of which is included as Annex B to this proxy statement, which Amended and Restated Voting Agreement amended and restated the Stockholder Voting Agreement, dated as of June 17, 2015, by and between Allergan and each of the individuals or entities listed on the signature pages thereto (which we refer to in this proxy statement as the "Initial Voting Agreement"). Unless otherwise indicated, all references to "dollars" or "$" in this proxy statement are references to U.S. dollars. If you are in any doubt about this transaction you should consult an independent financial advisor.

Q:

WHAT ARE THE PROPOSED TRANSACTIONS ABOUT WHICH I AM BEING ASKED TO VOTE?

A:

Allergan has agreed to acquire KYTHERA under the terms of the Amended and Restated Merger Agreement. Pursuant to the Amended and Restated Merger Agreement, Merger Sub will merge with and into KYTHERA (which merger is referred to in this proxy statement as the "Merger"), with KYTHERA continuing as the surviving corporation (referred to in this proxy statement as the "Surviving Corporation"). Following the Merger, KYTHERA will be an indirect wholly owned subsidiary of Allergan and the KYTHERA common stock will be delisted from The NASDAQ Global Select Market (referred to in this proxy statement as "NASDAQ"), deregistered under the Securities Exchange Act of 1934, as amended (referred to in this proxy statement as the "Exchange Act") and cease to be publicly traded.

KYTHERA stockholders are being asked to (i) adopt the Amended and Restated Merger Agreement, (ii) approve the adjournment of the KYTHERA special meeting to another date and place if necessary or appropriate to solicit additional votes in favor of adopting the Amended and Restated Merger Agreement, and (iii) approve, on a non-binding, advisory basis, the compensation to be paid by KYTHERA to its named executive officers that is based on or otherwise relates to the Merger.

The adoption of the Amended and Restated Merger Agreement by the KYTHERA stockholders is a condition to the consummation of the Merger. See the section entitled "The Amended and

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Restated Merger Agreement—Conditions to the Consummation of the Merger" beginning on page 83 of this proxy statement.

Q:

WHY AM I RECEIVING THIS PROXY STATEMENT?

A:

KYTHERA is sending these materials to its stockholders to help them decide how to vote their shares of KYTHERA common stock with respect to matters to be considered at the KYTHERA special meeting.

The consummation of the Merger requires the approval of the KYTHERA stockholders. To obtain the required stockholder approval, KYTHERA will hold the KYTHERA special meeting at which KYTHERA will ask its stockholders to approve (i) the adoption of the Amended and Restated Merger Agreement, (ii) the adjournment of the KYTHERA special meeting to another date and place if necessary or appropriate to solicit additional votes in favor of adopting the Amended and Restated Merger Agreement, and (iii) a non-binding, advisory proposal relating to the compensation to be paid by KYTHERA to its named executive officers that is based on or otherwise relates to the Merger. Further information about the KYTHERA special meeting and the Merger is contained in this proxy statement. The Merger is not conditioned on the approval of the adjournment of the KYTHERA special meeting or the compensation payable to KYTHERA's named executive officers that is based on or otherwise relates to the Merger.

The board of directors of KYTHERA (referred to in this proxy statement as the "KYTHERA Board") is soliciting proxies from its stockholders in connection with the KYTHERA special meeting using this proxy statement.

The enclosed proxy materials allow you to grant a proxy or vote your shares by telephone or Internet without attending the KYTHERA special meeting in person.

Your vote is very important. You are encouraged to submit your proxy or vote your shares by telephone or Internet as soon as possible, even if you do plan to attend the KYTHERA special meeting in person.

Q:

WHAT WILL KYTHERA STOCKHOLDERS RECEIVE IN THE MERGER?

A:

As a result of the Merger, each share of KYTHERA common stock issued and outstanding immediately prior to the effective time of the Merger, other than (i) any shares held by KYTHERA as treasury stock or owned by Allergan or Merger Sub or any of their respective subsidiaries, which will be canceled without consideration, and any shares subject to any unvested KYTHERA restricted stock award which is to be assumed by Allergan in the Merger (the shares described in (i) are referred to in this proxy statement as "excluded shares") and (ii) shares of KYTHERA common stock held by KYTHERA stockholders who have properly demanded appraisal and otherwise complied with applicable Delaware law and not effectively withdrawn any demand for, or lost the right to, appraisal under Delaware law, which will become entitled to the payment of the fair value of such shares determined in accordance with Delaware law as described under the section entitled "Appraisal Rights" beginning on page 120 of this proxy statement (the shares described in (ii) are referred to in this proxy statement as "dissenting shares"), will be converted into the right to receive $75.00 in cash, without interest (referred to in this proxy statement as the "Merger Consideration").

Q:

WHAT WILL HOLDERS OF KYTHERA EQUITY AWARDS RECEIVE IN THE MERGER?

A:

Stock Options: As of the effective time of the Merger, each option to purchase KYTHERA common stock (referred to in this proxy statement as a "KYTHERA Stock Option") granted under any KYTHERA equity plan that is outstanding and unexercised immediately prior to the

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effective time of the Merger, whether or not then vested or exercisable and other than as described in the next paragraph for certain vested KYTHERA Stock Options, will be assumed by Allergan and will be converted into an option to purchase a number of validly issued, fully paid and nonassessable ordinary shares of Allergan (such shares are referred to in this proxy statement as "Allergan ordinary shares" and each such option to purchase Allergan ordinary shares is referred to in this proxy statement as an "Allergan Stock Option") and will remain subject to the same vesting (if unvested) and other terms and conditions as applied to the applicable KYTHERA Stock Option immediately prior to the effective time of the Merger (but taking into account any changes thereto provided for in the applicable KYTHERA equity plan, in any award agreement or in the KYTHERA Stock Option by reason of the Amended and Restated Merger Agreement or the Merger, including the Equity Award Amendment (as defined in "The Merger—Interests of KYTHERA's Directors and Executive Officers after the Merger—Treatment of KYTHERA Stock Options and Other KYTHERA Equity Awards" beginning on page 75 of this proxy statement)). As of the effective time of the Merger, each such Allergan Stock Option as so assumed and converted will be exercisable for that whole number of Allergan ordinary shares equal to the product (which product will be rounded down to the nearest whole share) of (i) the number of shares of KYTHERA common stock subject to such KYTHERA Stock Option immediately prior to the effective time of the Merger multiplied by (ii) the quotient determined by dividing $75.00 by the volume weighted average price of Allergan ordinary shares (as reported by Bloomberg L.P. or, if not reported by Bloomberg L.P., in another authoritative source mutually selected by KYTHERA and Allergan) for a ten trading day period, starting with the opening of trading on the twelfth trading day prior to the closing date of the Merger (referred to in this proxy statement as the "Closing Date") and ending with the closing of trading on the third to last trading day prior to the Closing Date (such volume weighted average price of Allergan ordinary shares is referred to in this proxy statement as the "Allergan VWAP"), and rounding the result to the nearest 1/10,000 of an Allergan ordinary share (such quotient referred to in this proxy statement as the "Stock Award Exchange Ratio"), at an exercise price per Allergan ordinary share equal to the quotient (which quotient will be rounded down to the nearest whole cent) obtained by dividing (x) the exercise price per share of KYTHERA common stock of such KYTHERA Stock Option by (y) the Stock Award Exchange Ratio.

At the effective time of the Merger, each vested outstanding KYTHERA Stock Option held by a KYTHERA non-employee director or any employee of KYTHERA who does not continue to be employed by the Surviving Corporation or any other affiliate of Allergan following the effective time of the Merger (such non-continuing employees of KYTHERA referred to in this proxy statement as the "Non-Continuing Employees") will be cancelled and converted into the right to receive an amount in cash, without interest, equal to the product determined by multiplying the number of shares of KYTHERA common stock subject to such KYTHERA Stock Option immediately prior to the effective time of the Merger by the excess, if any, of $75.00 minus the per share exercise price of such KYTHERA Stock Option, subject to applicable withholding taxes.

Restricted Share Awards: As of the effective time of the Merger, each outstanding KYTHERA restricted stock award (referred to in this proxy statement as a "KYTHERA Restricted Share Award") granted under any KYTHERA equity plan that is not then vested will be assumed by Allergan and will be converted into an award of restricted Allergan ordinary shares (referred to in this proxy statement as "Allergan Restricted Share Awards"), and each Allergan Restricted Share Award will remain subject to the same terms and conditions as applied to the applicable KYTHERA Restricted Share Award immediately prior to the effective time of the Merger (but taking into account any changes thereto provided for in the applicable KYTHERA equity plan, in any award agreement or in the KYTHERA Restricted Share Award by reason of the Amended and Restated Merger Agreement or the Merger, including the Equity Award Amendment). As of the effective time of the Merger, the number of Allergan ordinary shares underlying each Allergan

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Restricted Share Award will be equal to the product (which will be rounded up to the nearest whole share) of the number of shares of KYTHERA common stock subject to the applicable KYTHERA Restricted Share Award multiplied by the Stock Award Exchange Ratio.

Restricted Stock Unit Awards: As of the effective time of the Merger, each outstanding KYTHERA restricted stock unit award (referred to in this proxy statement as a "KYTHERA RSU Award" and collectively with KYTHERA Stock Options and KYTHERA Restricted Share Awards, as "KYTHERA Equity Awards") issued under any KYTHERA equity plan that is not then vested will be assumed by Allergan and will be converted into a restricted stock unit award for Allergan ordinary shares (each referred to in this proxy statement as an "Allergan RSU Award"), and each Allergan RSU Award will remain subject to the same terms and conditions as applied to the applicable KYTHERA RSU Award immediately prior to the effective time of the Merger (but taking into account any changes thereto provided for in the applicable KYTHERA equity plan, in any award agreement or in the KYTHERA RSU Award by reason of the Amended and Restated Merger Agreement or the Merger, including the Equity Award Amendment). As of the effective time of the Merger, the number of Allergan ordinary shares underlying each Allergan RSU Award will be equal to the product (which will be rounded up to the nearest whole share) of the number of shares of KYTHERA common stock underlying the applicable KYTHERA RSU Award multiplied by the Stock Award Exchange Ratio. Further, Allergan will have the ability to adjust any dividend equivalent rights associated with the Allergan RSU Awards, to reflect dividends on Allergan ordinary shares giving effect to the changes and adjustments contemplated to the corresponding KYTHERA RSU Awards by reason of the Amended and Restated Merger Agreement or the Merger.

See the section entitled "The Amended and Restated Merger Agreement—Treatment of KYTHERA Stock Options and Other KYTHERA Equity Awards" beginning on page 75 of this proxy statement.

Q:

WHEN WILL THE MERGER BE CONSUMMATED?

A:

The parties currently expect that the Merger will be consummated during the third quarter of 2015. KYTHERA cannot predict, however, the actual date on which the Merger will be consummated, or whether it will be consummated, because the Merger is subject to factors beyond KYTHERA's control. See the section entitled "The Amended and Restated Merger Agreement—Conditions to the Consummation of the Merger" beginning on page 102 of this proxy statement.

Q:

WHO IS ENTITLED TO VOTE?

A:

The KYTHERA Board has fixed the close of business on [    ·    ], 2015 as the record date of the KYTHERA special meeting (referred to in this proxy statement as the "record date"). If you were a KYTHERA stockholder of record as of the close of business on [    ·    ], 2015, you are entitled to receive notice of and to vote at the KYTHERA special meeting and any adjournments thereof.

Q:

WHAT ARE KYTHERA STOCKHOLDERS BEING ASKED TO VOTE ON AND WHY IS THIS APPROVAL NECESSARY?

A:

KYTHERA stockholders are being asked to vote on the following proposals:

1.

to adopt the Amended and Restated Merger Agreement, a copy of which is attached as Annex A to this proxy statement (referred to in this proxy statement as the "Merger Proposal");

2.

to approve the adjournment of the KYTHERA special meeting to another date and place if necessary or appropriate to solicit additional votes in favor of the Merger Proposal (referred to in this proxy statement as the "Adjournment Proposal"); and

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3.

to approve, on a non-binding, advisory basis, the compensation to be paid to KYTHERA's named executive officers that is based on or otherwise relates to the Merger, discussed under the section entitled "The Merger—Interests of KYTHERA's Directors and Executive Officers in the Merger—Quantification of Payments and Benefits to KYTHERA's Named Executive Officers" beginning on page 78 of this proxy statement (referred to in this proxy statement as the "Merger-Related Named Executive Officer Compensation Proposal").


KYTHERA stockholder approval of the Merger Proposal is required for consummation of the Merger.

KYTHERA stockholder approval of the Adjournment Proposal and the Merger-Related Named Executive Officer Compensation Proposal is not required for consummation of the Merger. No other matters are intended to be brought before the KYTHERA special meeting.

The Amended and Restated Merger Agreement provides that KYTHERA may not postpone or adjourn the KYTHERA special meeting to a date that is more than 30 days after the date on which the KYTHERA special meeting was originally scheduled.

Q:

WHAT VOTE IS REQUIRED TO APPROVE EACH PROPOSAL AT THE KYTHERA SPECIAL MEETING?

A:

The Merger Proposal: The affirmative vote of a majority of the outstanding shares of KYTHERA common stock held by stockholders of record as of [    ·    ], 2015 is required to approve the Merger Proposal. If you are a KYTHERA stockholder and you abstain from voting or fail to vote, or fail to instruct your broker, bank or other nominee how to vote on the Merger Proposal, it will have the same effect as a vote cast against the Merger Proposal.

The Adjournment Proposal: Assuming a quorum is present, the affirmative vote of at least a majority of the votes cast with respect to shares of KYTHERA common stock at the KYTHERA special meeting is required to approve the Adjournment Proposal. For the Adjournment Proposal, if a KYTHERA stockholder is present in person or by proxy at the KYTHERA special meeting and chooses to abstain from voting with respect to the Adjournment Proposal, it will have no effect on the outcome of the Adjournment Proposal (except that the fact that such stockholder is present in person or by proxy at the KYTHERA special meeting will be counted in determining whether a quorum is present). If a KYTHERA stockholder fails to vote and is not present in person or by proxy at the KYTHERA special meeting, it will have no effect on the vote count for the Adjournment Proposal (except that the fact that such stockholder is not present in person or by proxy at the KYTHERA special meeting will be counted in determining whether a quorum is present).

The Merger-Related Named Executive Officer Compensation Proposal: Assuming a quorum is present, the affirmative vote of a majority of the votes cast with respect to shares of KYTHERA common stock at the KYTHERA special meeting is required to approve the Merger-Related Named Executive Officer Compensation Proposal. The KYTHERA stockholders' vote regarding the Merger-Related Named Executive Officer Compensation Proposal is an advisory vote, and therefore is not binding on KYTHERA or the KYTHERA Board or the compensation committee of KYTHERA. Since compensation and benefits to be paid or provided in connection with the Merger are based on contractual arrangements with the named executive officers, the outcome of this advisory vote will not affect the obligation to make these payments and these payments may still be made even if the KYTHERA stockholders do not approve, by advisory (non-binding) vote, the Merger-Related Named Executive Officer Compensation Proposal. For the Merger-Related Named Executive Officer Compensation Proposal, if a KYTHERA stockholder is present in person or by proxy at the KYTHERA special meeting and chooses to abstain from voting with respect to the Merger-Related Named Executive Officer Compensation Proposal, it will have no effect on the

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outcome of the Merger-Related Named Executive Officer Compensation Proposal (except that the fact that such stockholder is present in person or by proxy at the KYTHERA special meeting will be counted in determining whether a quorum is present). If a KYTHERA stockholder fails to vote and is not present in person or by proxy at the KYTHERA special meeting, it will have no effect on the vote count for the Merger-Related Named Executive Officer Compensation Proposal (except that the fact that such stockholder is not present in person or by proxy at the KYTHERA special meeting will be counted in determining whether a quorum is present).

Q:

WHAT IS THE EFFECT OF THE AMENDED AND RESTATED VOTING AGREEMENT?

A:

In connection with the Merger, on June 17, 2015, each of KYTHERA's directors and certain of their affiliates (referred to in this proxy statement as the "Supporting Stockholders") entered into the Initial Voting Agreement with Allergan, which was subsequently amended and restated by the Amended and Restated Voting Agreement. Pursuant to the Amended and Restated Voting Agreement, each Supporting Stockholder has agreed, among other things, to vote certain of his, her or its shares of KYTHERA common stock in favor of the Merger Proposal and the Adjournment Proposal. As of the record date, the Supporting Stockholders owned in the aggregate approximately [    ·    ] shares of KYTHERA common stock (not including any shares of KYTHERA common stock subject to KYTHERA Stock Options), of which approximately [    ·    ] of such shares of KYTHERA common stock are subject to the Amended and Restated Voting Agreement, representing approximately [    ·    ]% of the shares of KYTHERA common stock outstanding as of the close of business on the record date. The Amended and Restated Voting Agreement does not change the number of votes required to approve the Merger Proposal or the Adjournment Proposal. See the section entitled "The Amended and Restated Voting Agreement" beginning on page 109 of this proxy statement.

Q:

HOW DOES THE KYTHERA BOARD RECOMMEND KYTHERA STOCKHOLDERS VOTE?

A:

The KYTHERA Board has determined that the Amended and Restated Merger Agreement and the transactions contemplated thereby, including the Merger, are advisable, fair to, and in the best interests of KYTHERA and the KYTHERA stockholders, has approved and declared advisable the Amended and Restated Merger Agreement and the transactions contemplated thereby, including the Merger, on the terms and subject to the conditions set forth therein, and recommends that KYTHERA stockholders vote their shares of KYTHERA common stock:

1.

"FOR" the Merger Proposal;

2.

"FOR" the Adjournment Proposal; and

3.

"FOR" the Merger-Related Named Executive Officer Compensation Proposal.

Q:

ARE THERE ANY RISKS RELATED TO THE MERGER THAT KYTHERA STOCKHOLDERS SHOULD CONSIDER IN DECIDING WHETHER TO VOTE ON THE PROPOSALS?

A:

Yes. Before making any decision on whether and how to vote, KYTHERA stockholders are urged to read carefully and in its entirety the section entitled "Cautionary Statement Regarding Forward-Looking Statements" section beginning on page 29 of this proxy statement. KYTHERA stockholders should also read and carefully consider other risk factors that are incorporated by reference into this proxy statement.

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Q:

DO ANY OF KYTHERA'S DIRECTORS OR EXECUTIVE OFFICERS HAVE INTERESTS IN THE MERGER THAT MAY DIFFER FROM THOSE OF KYTHERA STOCKHOLDERS?

A:

Yes. KYTHERA's directors and executive officers have interests in the Merger that are different from, or in addition to, the interests of KYTHERA stockholders. See the section entitled "The Merger—Interests of KYTHERA's Directors and Executive Officers in the Merger" beginning on page 74 of this proxy statement. The members of KYTHERA's Board were aware of and considered these interests, among other matters, in evaluating the Amended and Restated Merger Agreement and the Merger and in recommending that KYTHERA stockholders vote to adopt the Amended and Restated Merger Agreement.

Q:

WHAT DO I NEED TO DO NOW?

A:

After carefully reading and considering the information contained or incorporated by reference in this proxy statement, please submit your proxy or voting instruction card for your shares as soon as possible so that your shares of KYTHERA common stock entitled to vote at the KYTHERA special meeting will be represented. Please follow the instructions set forth on the proxy card or on the voting instruction card provided by the record holder if your shares are held in "street name" through your broker, bank or other nominee.

Q:

HOW DO I VOTE?

A:

If you are a stockholder of record of KYTHERA as of the record date, you may submit your proxy before the KYTHERA special meeting in one of the following ways:

1.

visit the website shown on your proxy card to submit your proxy via the Internet;

2.

call the toll-free number for telephone proxy submission shown on your proxy card; or

3.

complete, sign, date and return the enclosed proxy card in the enclosed postage-paid envelope.

You may also cast your vote in person at the KYTHERA special meeting.

If your shares are held in "street name," through a broker, bank or other nominee, that institution will send you separate instructions describing the procedure for voting your shares. "Street name" shareholders or stockholders who wish to vote in person at the meeting will need to obtain a proxy form from their broker, bank or other nominee.

Q:

HOW MANY VOTES DO I HAVE?

A:

You are entitled to one vote for each share of KYTHERA common stock that you owned as of [    ·    ], the record date. As of the close of business on the record date, [    ·    ] shares of KYTHERA common stock were outstanding.

Q:

WHAT IF I SELL MY SHARES OF KYTHERA COMMON STOCK BEFORE THE KYTHERA SPECIAL MEETING?

A:

If you transfer your shares of KYTHERA common stock after the record date but before the KYTHERA special meeting, you will, unless you provide the transferee of your shares with a proxy, retain your right to vote at the KYTHERA special meeting but will have transferred the right to receive the Merger Consideration. In order to receive the Merger Consideration, you must hold your shares through the effective time of the Merger.

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Q:

SHOULD I SEND IN MY STOCK CERTIFICATES NOW?

A:

No. To the extent certain KYTHERA stockholders have certificated shares, such KYTHERA stockholders should keep their existing stock certificates at this time. After the Merger is completed, KYTHERA stockholders will receive a letter of transmittal and written instructions for exchanging their stock certificates for the Merger Consideration.

Q:

WHEN AND WHERE IS THE KYTHERA SPECIAL MEETING?

A:

The KYTHERA special meeting will be held at [    ·    ], at [    ·    ] (local time), on [    ·    ], 2015.

Q:

WHAT CONSTITUTES A QUORUM?

A:

The holders of a majority in voting power of the issued and outstanding KYTHERA common stock entitled to vote that are present in person or represented by proxy will constitute a quorum for the KYTHERA special meeting. Abstentions are considered present for purposes of determining a quorum. As of the record date, [    ·    ] shares of KYTHERA common stock were outstanding, thus [    ·    ] shares present in person or represented by proxy will constitute a quorum for the meeting.

Q:

IF MY SHARES ARE HELD IN "STREET NAME" BY A BROKER, BANK OR OTHER NOMINEE, WILL MY BROKER, BANK OR OTHER NOMINEE VOTE MY SHARES FOR ME?

A:

If your shares are held in "street name" in a stock brokerage account or by a bank or other nominee, you must provide the record holder of your shares with instructions on how to vote your shares. Please follow the voting instructions provided by your broker, bank or other nominee. Please note that you may not vote shares held in "street name" by returning a proxy card directly to KYTHERA or by voting in person at the KYTHERA special meeting unless you obtain a "legal proxy," which you must obtain from your broker, bank or other nominee.

Under the rules of NASDAQ, brokers who hold shares in "street name" for a beneficial owner of those shares typically have the authority to vote in their discretion on "routine" proposals when they have not received instructions from beneficial owners. However, brokers are not allowed to exercise their voting discretion with respect to the approval of matters that NASDAQ determines to be "non-routine" without specific instructions from the beneficial owner. It is expected that all proposals to be voted on at the KYTHERA special meeting will be "non-routine" matters. Broker non-votes occur when a broker or nominee is not instructed by the beneficial owner of shares how to vote on a particular proposal for which the broker does not have discretionary voting power.

If you are a KYTHERA stockholder and you do not instruct your broker, bank or other nominee on how to vote your shares:

1.

your broker, bank or other nominee may not vote your shares on the Merger Proposal, which broker non-votes will have the same effect as a vote "AGAINST" such proposal;



2.

your broker, bank or other nominee may not vote your shares on the Adjournment Proposal, which broker non-votes will have no effect on the vote count for this proposal (and your shares will not count as present at the KYTHERA special meeting for purposes of determining whether a quorum is present); and



3.

your broker, bank or other nominee may not vote your shares on the Merger-Related Named Executive Officer Compensation Proposal, which broker non-votes will have no effect on the vote count for this proposal (and your shares will not count as present at the KYTHERA special meeting for purposes of determining whether a quorum is present).

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Q:

HOW DO I VOTE SHARES HELD OR ACQUIRED THROUGH AN EMPLOYEE PROGRAM?

A:

If you are a KYTHERA stockholder of record, the shares listed on your proxy card will include the following shares, if applicable:

•

shares acquired under the KYTHERA Biopharmaceuticals, Inc. 2004 Stock Plan, as amended;

•

shares acquired under the KYTHERA Biopharmaceuticals, Inc. 2012 Equity Incentive Award Plan;

•

shares acquired under the 2014 Employment Commencement Incentive Plan; and

•

shares acquired under the 2015 Employee Stock Purchase Plan.

Please see the Q&A above entitled "How do I vote?" for further information on how to vote such shares.

If your shares are held through a broker, bank or other nominee, that institution will send you separate instructions describing the procedure for voting your shares.

Q:

WHAT IF I DO NOT VOTE?

A:

If you are a KYTHERA stockholder and you fail to vote, fail to submit a proxy or fail to return a voting instruction card instructing your broker, bank or other nominee how to vote on the Merger Proposal or you respond with an "abstain" vote on the Merger Proposal, this will have the same effect as a vote cast against the Merger Proposal.

If you are a KYTHERA stockholder and you fail to vote, fail to submit a proxy or fail to return a voting instruction card instructing your broker, bank or other nominee how to vote on the Adjournment Proposal or Merger-Related Named Executive Officer Compensation Proposal, this will have no effect on the outcome of such proposals. If you respond with an "abstain" vote on the Adjournment Proposal or Merger-Related Named Executive Officer Compensation Proposal, your proxy will have no effect on the outcome of such proposals.

If you are a KYTHERA stockholder and you fail to vote, fail to submit a proxy or fail to return a voting instruction card instructing your broker, bank or other nominee how to vote on any of the proposals, your shares will not count as present at the KYTHERA special meeting for purposes of determining whether a quorum is present. If you vote on any proposal or return a voting instruction card, regardless of how you vote, or provide a proxy, your shares will count as present at the KYTHERA special meeting for purposes of determining whether a quorum is present.

Please note, however, if you sign and return your proxy or voting instruction card without indicating how to vote on any particular proposal (and you do not change your vote after delivering your proxy or voting instruction card), the shares of KYTHERA common stock represented by your proxy will be voted for each KYTHERA proposal in accordance with the recommendation of the KYTHERA Board.

Please see the Q&A below entitled "May I change my vote after I have delivered my proxy or voting instruction card?" for further information on how to change your vote.

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Q:

MAY I CHANGE MY VOTE AFTER I HAVE DELIVERED MY PROXY OR VOTING INSTRUCTION CARD?

A:

Yes. You may change your vote or revoke a proxy at any time before your proxy is voted at the KYTHERA special meeting. If you are a KYTHERA stockholder of record, you can do this by:

•

delivering a written notice of revocation to KYTHERA's Corporate Secretary at or before the KYTHERA special meeting at the following address:

KYTHERA Biopharmaceuticals, Inc.
30930 Russell Ranch Road, 3rd floor
Westlake Village, California 91362
Attention: Keith Klein, Corporate Secretary

•

presenting to KYTHERA's Corporate Secretary, at or before the KYTHERA special meeting at the address above, a later dated proxy executed by the person who executed the prior proxy;



•

submitting another proxy by telephone or via the Internet (your latest telephone or Internet voting instructions will be followed); or



•

attending the KYTHERA special meeting and voting in person.

If you are a KYTHERA stockholder whose shares are held in "street name" by a broker, bank or other nominee, you may revoke your proxy and vote your shares in person at the KYTHERA special meeting only in accordance with applicable rules and procedures as employed by such broker, bank or other nominee. If your shares are held in an account at a broker, bank or other nominee, you should contact your broker, bank or other nominee to change your vote.

If you hold shares indirectly in the KYTHERA benefits plans, you should contact the trustee of your plan, as applicable, to change your vote of the shares allocated to your benefit plan.

Attending the KYTHERA special meeting will not automatically revoke a proxy that was submitted through the Internet or by telephone or mail. If you wish to change your vote at the KYTHERA special meeting, you must vote by ballot at such meeting to change your vote.

Q:

WHAT SHOULD I DO IF I RECEIVE MORE THAN ONE SET OF VOTING MATERIALS?

A:

KYTHERA stockholders may receive more than one set of voting materials, including multiple copies of this proxy statement and multiple proxy cards or voting instruction cards. For example, if you hold KYTHERA common stock in more than one brokerage account, you will receive a separate voting instruction card for each brokerage account in which you hold such shares. If you are a holder of record of KYTHERA common stock and your shares are registered in more than one name, you will receive more than one proxy card.

Please complete, sign, date and return each proxy card and voting instruction card that you receive or otherwise follow the voting instructions set forth in this proxy statement to ensure that you vote every share of KYTHERA common stock that you own.

Q:

WHERE CAN I FIND THE VOTING RESULTS OF THE KYTHERA SPECIAL MEETING?

A:

Final voting results for the KYTHERA special meeting are expected to be published in a Current Report on Form 8-K to be filed by KYTHERA with the U.S. Securities and Exchange Commission (referred to this proxy statement as the "SEC") within four business days after the KYTHERA special meeting. A copy of this Current Report on Form 8-K will be available after filing with the SEC on the KYTHERA website.

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Q:

ARE KYTHERA STOCKHOLDERS ENTITLED TO APPRAISAL RIGHTS?

A:

Yes. KYTHERA stockholders are entitled to appraisal rights under Section 262 of the General Corporation Law of the State of Delaware (referred to in this proxy statement as the "DGCL"), provided they do not vote in favor of the Merger Proposal and otherwise satisfy the conditions set forth in Section 262 of the DGCL. More information regarding these appraisal rights is provided in this proxy statement, and the provisions of Section 262 of the DGCL that grant appraisal rights and govern such procedures are attached as Annex F to this proxy statement. You should read these provisions carefully and in their entirety. See the section entitled "Appraisal Rights" beginning on page 120 of this proxy statement.

Q:

WHAT ARE THE U.S. FEDERAL INCOME TAX CONSEQUENCES OF THE MERGER TO KYTHERA STOCKHOLDERS?

A:

For U.S. federal income tax purposes, the exchange of KYTHERA common stock for cash pursuant to the Merger will be treated as a taxable transaction. KYTHERA stockholders that are U.S. holders will generally recognize gain or loss equal to the difference, if any, between (i) the amount of cash received by such holder in the Merger, and (ii) the stockholder's tax basis in KYTHERA common stock surrendered. Such gain or loss generally will be long-term capital gain or loss if the U.S. holder's holding period of the KYTHERA common stock surrendered exceeds one year at the effective time of the Merger.

KYTHERA stockholders should consult their tax advisors as to the particular tax consequences to them of the Merger, including the effect of U.S. federal, state and local tax laws and foreign tax laws. For a more detailed discussion of the material U.S. federal income tax consequences of the Merger, see the section entitled "Certain Tax Consequences of the Merger—U.S. Federal Income Tax Considerations" beginning on page 112 of this proxy statement.

Q:

WHAT HAPPENS IF THE MERGER IS NOT COMPLETED?

A:

If the Merger is not completed, KYTHERA stockholders will not receive any consideration for their shares of KYTHERA common stock. Instead, KYTHERA will remain an independent public company and its common stock will continue to be listed and traded on NASDAQ. The Amended and Restated Merger Agreement contains certain customary termination rights for both KYTHERA and Allergan, including in the event that the Merger is not consummated by March 17, 2016 (referred to in this proxy statement as the "Outside Date"). The Amended and Restated Merger Agreement further provides that, upon termination of the Amended and Restated Merger Agreement to accept a competing acquisition proposal and in certain other specified circumstances, KYTHERA may be required to pay Allergan a termination fee of $69.75 million in cash, as described under the section entitled "The Amended and Restated Merger Agreement—Termination of the Amended and Restated Merger Agreement; Termination Fee" beginning on page 104 of this proxy statement.

Q:

WHOM SHOULD I CONTACT IF I HAVE ANY QUESTIONS ABOUT THE PROXY MATERIALS OR VOTING?

A:

If you have any questions about the proxy materials or if you need assistance submitting your proxy or voting your shares or need additional copies of this proxy statement or the enclosed proxy card, you should contact MacKenzie Partners Inc., the proxy solicitation agent, by mail at 105 Madison Avenue, New York, NY 10016, or by telephone toll-free at (800) 322-2885 or collect at (212) 929-5500.

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Q:

WHERE CAN I FIND MORE INFORMATION ABOUT KYTHERA?

A:

You can find more information about KYTHERA from the various sources described under the section entitled "Where You Can Find More Information" beginning on page 127 of this proxy statement.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

        This proxy statement contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Statements contained in this communication that refer to KYTHERA's estimated or anticipated future results, including estimated synergies, or other non-historical facts are forward-looking statements that reflect KYTHERA's current perspective of existing trends and information as of the date of this communication. Forward-looking statements generally will be accompanied by words such as "anticipate," "believe," "plan," "could," "should," "estimate," "expect," "forecast," "outlook," "guidance," "intend," "may," "might," "will," "possible," "potential," "predict," "project," or other similar words, phrases or expressions.

        Such forward-looking statements include, but are not limited to, statements about the benefits of the Merger, including KYTHERA's plans, objectives, expectations and intentions and the expected timing of completion of the Merger. We are not able to predict all of the factors that may affect future results. It is important to note that KYTHERA's goals and expectations are not predictions of actual performance. Some of these risks and uncertainties are outside our control and our actual results may differ materially from KYTHERA's current expectations depending upon a number of factors affecting KYTHERA's business and risks associated with acquisition transactions.

        These factors include, among others:

•

the possibility that all of the conditions to the completion of the Merger may not be completed in a timely manner or at all, which may adversely affect our business and the price of our shares;



•

the possibility that the KYTHERA stockholders will not provide sufficient votes, under applicable law and the Amended and Restated Merger Agreement, to adopt the Amended and Restated Merger Agreement, which is a condition to the completion of the Merger;



•

the costs, fees, expenses and charges related to the Merger;



•

an unsolicited offer of another company to acquire KYTHERA;



•

the occurrence of any event, change or other circumstance that could give rise to the termination of the Amended and Restated Merger Agreement and, in the certain cases, the payment by us of a termination fee of $69.75 million (approximately 3.25% of the equity value of the transaction) in cash;



•

the effect of the announcement and pendency of the Merger on our strategic plans, business relationships, operating results and business generally, including the potential adverse effect on our business, properties, and operations because of certain covenants we agreed to in the Amended and Restated Merger Agreement;



•

diversion of our management's attention from our ongoing business operations due to the pendency of the Merger and related matters;



•

the market potential of KYBELLA™;



•

the anticipated size of the markets, market acceptance of and continued demand for KYTHERA's products;



•

the impact of competitive products and pricing;



•

access to available financing (including financing for the Merger or refinancing of debt) on a timely basis and on reasonable terms;



•

the risks of fluctuations in foreign currency exchange rates;

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•

the risks and uncertainties normally incident to the pharmaceutical industry, including product liability claims and the availability of product liability insurance on reasonable terms;



•

the difficulty of predicting the timing or outcome of pending or future litigation or government investigations;



•

periodic dependence on a small number of products for a material source of net revenue or income; variability of trade buying patterns;



•

changes in economic, business, competitive, technological, regulatory factors and/or generally accepted accounting principles;



•

risks that the carrying values of assets may be negatively impacted by future events and circumstances; the timing and success of product launches;



•

the difficulty of predicting the timing or outcome of product development efforts and regulatory agency approvals or actions, if any;



•

costs and efforts to defend or enforce intellectual property rights; difficulties or delays in manufacturing; the availability and pricing of third party sourced products and materials;



•

successful compliance with governmental regulations applicable to KYTHERA's facilities, products and/or businesses; changes in the laws and regulations affecting, among other things, pricing and reimbursement of pharmaceutical products; the loss of key senior management or scientific staff; and



•

such other risks and uncertainties detailed in KYTHERA's periodic public filings with the SEC, including but not limited to KYTHERA's annual report on Form 10-K for the year ended December 31, 2014, KYTHERA's Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2015 and in other KYTHERA documents that are incorporated by reference into this proxy statement and from time to time in KYTHERA's other investor communications.

        Forward-looking statements speak only as of the date of this proxy statement. Except as expressly required by law, KYTHERA disclaims any intent or obligation to update or revise these forward-looking statements, whether as a result of new information, future events or otherwise.

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MARKET PRICE OF KYTHERA COMMON STOCK AND DIVIDEND INFORMATION

        The table below sets forth, for the calendar quarters indicated, the high and low sales prices per share, as well as the dividend paid per share, of KYTHERA common stock, which trades on NASDAQ under the symbol "KYTH."

        On June 16, 2015, the last full trading day before the public announcement of the signing of the Initial Merger Agreement, the closing sale price per share of KYTHERA common stock on NASDAQ was $60.72. On [    ·    ], 2015, the latest practicable full trading day before the date of this proxy statement, the closing sale price per share of KYTHERA common stock on NASDAQ was $[    ·    ].

        The KYTHERA Board has the power to determine the amount and frequency of the payment of dividends. Decisions regarding whether to pay dividends and the amount of any dividends are based upon, among other things, compliance with the DGCL, compliance with agreements governing KYTHERA's indebtedness, earnings, cash requirements, results of operations, cash flows and financial condition and other factors that the KYTHERA Board considers important. KYTHERA does not currently pay dividends. While KYTHERA anticipates that if the Merger were not consummated it would continue not to pay dividends, there are no assurances that will be the case. Under the Amended and Restated Merger Agreement, until the effective time of the Merger, KYTHERA is not permitted to authorize or pay any dividends on, or make any other distributions in respect of, any of its capital stock.

        The above tables show only historical comparisons. KYTHERA stockholders are urged to obtain current market quotations for KYTHERA common stock and to review carefully the other information contained in this proxy statement or incorporated by reference into this proxy statement in considering whether to adopt the Amended and Restated Merger Agreement.

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THE KYTHERA SPECIAL MEETING

Date, Time and Place of the KYTHERA Special Meeting

        The KYTHERA special meeting of KYTHERA stockholders will be held at [    ·    ] at [    ·    ] (local time) on [    ·    ], 2015. On or about [    ·    ], 2015, KYTHERA commenced mailing this proxy statement and the enclosed form of proxy to its stockholders entitled to vote at the KYTHERA special meeting.

Purpose of the KYTHERA Special Meeting

        At the KYTHERA special meeting, KYTHERA stockholders will be asked to:

(1)

adopt the Amended and Restated Merger Agreement, a copy of which is attached as Annex A to this proxy statement;



(2)

approve the adjournment of the KYTHERA special meeting to another date and place if necessary or appropriate to solicit additional votes in favor of the Merger Proposal; and



(3)

approve, on a non-binding, advisory basis, the compensation to be paid to KYTHERA's named executive officers that is based on or otherwise relates to the Merger, as disclosed pursuant to Item 402(t) of Regulation S-K in the section entitled "The Merger—Interests of KYTHERA's Directors and Executive Officers in the Merger—Quantification of Payments and Benefits to KYTHERA's Named Executive Officers" beginning on page [    ·    ] of this proxy statement.

Recommendation of the KYTHERA Board

        The KYTHERA Board recommends that you vote "FOR" the Merger Proposal, "FOR" the Adjournment Proposal and "FOR" the Merger-Related Named Executive Officer Compensation Proposal. See the section entitled "The Merger—Recommendation of the KYTHERA Board and KYTHERA's Reasons for the Merger" beginning on page 54 of this proxy statement.

        Completion of the Merger is conditioned upon approval of the Merger Proposal, but is not conditioned on the approval of the Adjournment Proposal or the Merger-Related Named Executive Officer Compensation Proposal.

Record Date and Quorum

Record Date

        The KYTHERA Board has fixed the close of business on [    ·    ], 2015 as the record date for determining the holders of shares of KYTHERA common stock entitled to receive notice of and to vote at the KYTHERA special meeting.

        As of the record date, there were [    ·    ] shares of KYTHERA common stock outstanding and entitled to vote at the KYTHERA special meeting held by [    ·    ] holders of record. Each share of KYTHERA common stock entitles the holder to one vote at the KYTHERA special meeting on each proposal to be considered at the KYTHERA special meeting. Shares of KYTHERA common stock that are held in treasury will not be entitled to vote at the KYTHERA special meeting.

Quorum

        The holders of a majority in voting power of the issued and outstanding KYTHERA common stock entitled to vote that are present in person or represented by proxy will constitute a quorum for the meeting. All shares of KYTHERA common stock, whether present in person or represented by proxy, including abstentions, will be treated as present for purposes of determining the presence or absence of a quorum for all matters voted on at the KYTHERA special meeting. As of the record

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date, [    ·    ] shares of KYTHERA common stock were outstanding, and, therefore, [    ·    ] shares present in person or represented by proxy will constitute a quorum for the KYTHERA special meeting.

        As of the record date, directors and executive officers of KYTHERA and their affiliates owned and were entitled to vote [    ·    ] shares of KYTHERA common stock, representing approximately [    ·    ]% of the shares of KYTHERA common stock outstanding on that date. Each of the KYTHERA directors and certain of their affiliates has entered into the Amended and Restated Voting Agreement pursuant to which he, she or it has agreed, among other things, to vote certain of his, her or its shares of KYTHERA common stock in favor of the Merger Proposal and the Adjournment Proposal. The shares of KYTHERA common stock subject to the Amended and Restated Voting Agreement constitute approximately [    ·    ]% of the voting power of the outstanding shares of KYTHERA common stock entitled to be cast at the KYTHERA special meeting. KYTHERA currently expects that its executive officers that have not entered into the Amended and Restated Voting Agreement will vote their shares in favor of the Merger Proposal, the Adjournment Proposal and the Merger- Related Named Executive Officer Compensation Proposal, although they have not entered into any agreements obligating them to do so.

Required Vote

Required Vote to Approve the Merger Proposal

        The affirmative vote of a majority of the outstanding shares of KYTHERA common stock held by stockholders of record as of [    ·    ], 2015 is required to approve the Merger Proposal. If you are a KYTHERA stockholder and you abstain from voting or fail to vote, or fail to instruct your broker, bank or other nominee how to vote on the Merger Proposal, it will have the same effect as a vote cast against the Merger Proposal.

Required Vote to Approve the Adjournment Proposal

        Assuming a quorum is present, the affirmative vote of at least a majority of the votes cast with respect to shares of KYTHERA common stock at the KYTHERA special meeting is required to approve the Adjournment Proposal. Abstentions and broker non-votes will have no effect on the outcome of this proposal.

Required Vote to Approve the Merger-Related Named Executive Officer Compensation Proposal

        Assuming a quorum is present, the affirmative vote of a majority of the votes cast with respect to shares of KYTHERA common stock at the KYTHERA special meeting is required to approve the Merger-Related Named Executive Officer Compensation Proposal. Abstentions and broker non-votes will have no effect on the outcome of this proposal. The stockholders' vote regarding the Merger-Related Named Executive Officer Compensation Proposal is an advisory vote, and therefore is not binding on KYTHERA or the KYTHERA Board or the compensation committee of KYTHERA. Since compensation and benefits to be paid or provided in connection with the Merger are based on contractual arrangements with the named executive officers, the outcome of this advisory vote will not affect the obligation to make these payments and these payments may still be made even if the KYTHERA stockholders do not approve, by advisory (non-binding) vote, the Merger-Related Named Executive Officer Compensation Proposal.

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Treatment of Abstentions; Failure to Vote

        For purposes of the KYTHERA special meeting, an abstention occurs when a KYTHERA stockholder attends the KYTHERA special meeting in person and does not vote or returns a proxy marked "ABSTAIN."

•

For the Merger Proposal, an abstention or a failure to vote or a failure to instruct your broker, bank or other nominee how to vote will have the same effect as a vote cast "AGAINST" this proposal.



•

For the Adjournment Proposal, if a KYTHERA stockholder is present in person or by proxy at the KYTHERA special meeting and chooses to abstain from voting with respect to the Adjournment Proposal, it will have no effect on the outcome of the Adjournment Proposal (except that the fact that such stockholder is present in person or by proxy at the KYTHERA special meeting will be counted in determining whether a quorum is present).



•

For the Merger-Related Named Executive Officer Compensation Proposal, if a KYTHERA stockholder is present in person or by proxy at the KYTHERA special meeting and chooses to abstain from voting with respect to the Merger-Related Named Executive Officer Compensation Proposal, it will have no effect on the outcome of the Merger-Related Named Executive Officer Compensation Proposal (except that the fact that such stockholder is present in person or by proxy at the KYTHERA special meeting will be counted in determining whether a quorum is present).

Voting of Proxies; Incomplete Proxies

        Giving a proxy means that a KYTHERA stockholder authorizes the persons named in the enclosed proxy card to vote its shares at the KYTHERA special meeting in the manner it directs. A KYTHERA stockholder may vote by proxy or in person at the KYTHERA special meeting. If you hold your shares of KYTHERA common stock in your name as a stockholder of record, to submit a proxy, you may use one of the following methods:

•

By Internet.  The web address and instructions for Internet proxy submission can be found on the enclosed proxy card. You will be required to provide your assigned control number located on the proxy card. Internet proxy submission via the web address indicated on the enclosed proxy card is available 24 hours a day. If you choose to submit your proxy by Internet, then you do not need to return the proxy card. To be valid, your Internet proxy must be received by 11:59 p.m. (U.S. Eastern Time) on the day preceding the KYTHERA special meeting.



•

By Telephone.  The toll-free number for telephone proxy submission can be found on the enclosed proxy card. You will be required to provide your assigned control number located on the proxy card. Telephone proxy submission is available 24 hours a day. If you choose to submit your proxy by telephone, then you do not need to return the proxy card. To be valid, your telephone proxy must be received by 11:59 p.m. (U.S. Eastern Time) on the day preceding the KYTHERA special meeting.



•

By Mail.  Mark the enclosed proxy card, sign and date it, and return it in the postage-paid envelope provided therewith. To be valid, your proxy by mail must be received by 11:59 p.m. (U.S. Eastern Time) on the day preceding the KYTHERA special meeting.



•

In Person.  You may also vote your shares in person at the KYTHERA special meeting.

        KYTHERA requests that KYTHERA stockholders submit their proxies over the Internet, by telephone or by completing and signing the accompanying proxy and returning it to KYTHERA as soon as possible in the enclosed postage-paid envelope. When the accompanying proxy is returned properly executed (including proper proxy submission by Internet or telephone), the shares of

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KYTHERA common stock represented by it will be voted at the KYTHERA special meeting in accordance with the instructions contained on the proxy card.

        If you sign and return your proxy or voting instruction card without indicating how to vote on any particular proposal, the KYTHERA common stock represented by your proxy will be voted "FOR" each proposal in accordance with the recommendation of the KYTHERA Board. Unless you check the box on your proxy card to withhold discretionary authority, the proxyholders may use their discretion to vote on the proposals relating to the KYTHERA special meeting.

        If your shares of KYTHERA common stock are held in "street name" by a broker, bank or other nominee, you should check the voting form used by that firm to determine whether you may give voting instructions by telephone or the Internet.

        EVERY KYTHERA STOCKHOLDER'S VOTE IS IMPORTANT. ACCORDINGLY, EACH KYTHERA STOCKHOLDER SHOULD SUBMIT ITS PROXY VIA THE INTERNET OR BY TELEPHONE, OR SIGN, DATE AND RETURN THE ENCLOSED PROXY CARD, WHETHER OR NOT THE KYTHERA STOCKHOLDER PLANS TO ATTEND THE KYTHERA SPECIAL MEETING IN PERSON.

Shares Held in "Street Name"

        If your shares of KYTHERA common stock are held in "street name" through a bank, broker or other nominee, you must instruct such bank, broker or other nominee on how to vote the shares by following the instructions that the bank, broker or other nominee provides you along with this proxy statement. Your bank, broker or other nominee, as applicable, may have an earlier deadline by which you must provide instructions to it as to how to vote your shares of KYTHERA common stock, so you should read carefully the materials provided to you by your bank, broker or other nominee.

        You may not vote shares held in "street name" by returning a proxy card directly to KYTHERA or by voting in person at the KYTHERA special meeting unless you provide a "legal proxy," which you must obtain from your broker, bank or other nominee. Further, brokers, banks or other nominees who hold shares of KYTHERA common stock on behalf of their customers may not give a proxy to KYTHERA to vote those shares with respect to any of the KYTHERA proposals without specific instructions from their customers, as brokers, banks and other nominees do not have discretionary voting power on any of the KYTHERA proposals. Therefore, if your shares of KYTHERA common stock are held in "street name" and you do not instruct your broker, bank or other nominee on how to vote your shares,

•

your broker, bank or other nominee may not vote your shares on the Merger Proposal, which broker non-votes will have the same effect as a vote "AGAINST" this proposal;



•

your broker, bank or other nominee may not vote your shares on the Adjournment Proposal, which broker non-votes will have no effect on the outcome of this proposal (except that the fact that such stockholder is not present in person or by proxy at the KYTHERA special meeting will be counted in determining whether a quorum is present);



•

your broker, bank or other nominee may not vote your shares on the Merger-Related Named Executive Officer Compensation Proposal, which broker non-votes will have no effect on the outcome of this proposal (except that the fact that such stockholder is not present in person or by proxy at the KYTHERA special meeting will be counted in determining whether a quorum is present).

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Revocability of Proxies and Changes to a KYTHERA Stockholder's Vote

        If you are a KYTHERA stockholder of record, you may revoke or change your proxy at any time before it is voted at the KYTHERA special meeting by:

•

sending a written notice of revocation to Keith Klein, Corporate Secretary of KYTHERA, at 30930 Russell Ranch Road, 3rd Floor, Westlake Village, California 91362 that is received by KYTHERA prior to 11:59 p.m. (U.S. Eastern Time) on the day preceding the KYTHERA special meeting, stating that you would like to revoke your proxy; or



•

submitting a new proxy bearing a later date (by Internet, telephone or mail) that is received by KYTHERA prior to 11:59 p.m. (U.S. Eastern Time) on the day preceding the KYTHERA special meeting; or



•

attending the KYTHERA special meeting and voting in person.

        If you are a KYTHERA stockholder whose shares are held in "street name" by a broker, bank or other nominee, you may revoke your proxy or voting instructions and vote your shares in person at the KYTHERA special meeting only in accordance with applicable rules and procedures as employed by your broker, bank or other nominee. If your shares are held in an account at a broker, bank or other nominee, you must follow the directions you receive from your bank, broker or other nominee in order to change or revoke your proxy or voting instructions and should contact your broker, bank or other nominee to do so.

        Attending the KYTHERA special meeting will NOT automatically revoke a proxy that was submitted through the Internet or by telephone or mail. You must vote by ballot at the KYTHERA special meeting to change your vote.

Solicitation of Proxies

        The cost of solicitation of proxies from KYTHERA stockholders will be borne by KYTHERA. KYTHERA will reimburse brokerage firms and other custodians, nominees and fiduciaries for reasonable expenses incurred by them in sending proxy materials to the beneficial owners of KYTHERA common stock. KYTHERA has retained a professional proxy solicitation firm, MacKenzie Partners Inc., to assist in the solicitation of proxies for a fee of up to $60,000 plus reasonable out-of-pocket expenses. In addition to solicitations by mail, KYTHERA's directors, officers and regular employees may solicit proxies personally or by telephone without additional compensation.

Assistance

        If you need assistance in completing your proxy card or have questions regarding the KYTHERA special meeting, please contact MacKenzie Partners Inc., the proxy solicitation agent for KYTHERA, by mail at 105 Madison Avenue, New York, NY 10016, or by telephone toll-free at (800) 322-2885 or collect at (212) 929-5500.

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KYTHERA PROPOSALS

Merger Proposal

        As discussed throughout this proxy statement, KYTHERA is asking its stockholders to approve the Merger Proposal. Pursuant to the Amended and Restated Merger Agreement, Allergan will acquire KYTHERA in the Merger. Merger Sub will merge with and into KYTHERA, with KYTHERA continuing as the Surviving Corporation. Following the Merger, KYTHERA will be an indirect wholly owned subsidiary of Allergan and the KYTHERA common stock will be delisted from NASDAQ, deregistered under the Exchange Act and cease to be publicly traded.

        Holders of shares of KYTHERA common stock should carefully read this proxy statement in its entirety, including the annexes, for more detailed information concerning the Amended and Restated Merger Agreement and the Merger. In particular, holders of shares of KYTHERA common stock are directed to the Amended and Restated Merger Agreement, a copy of which is attached as Annex A to this proxy statement.

        Completion of the Merger is conditioned on approval of the Merger Proposal.

Vote Required and KYTHERA Board Recommendation

        The affirmative vote of a majority of the outstanding shares of KYTHERA common stock held by stockholders of record as of the close of business on [    ·    ], 2015 is required to approve the Merger Proposal. If you are a KYTHERA stockholder and you abstain from voting or fail to vote, or fail to instruct your broker, bank or other nominee how to vote on the Merger Proposal, it will have the same effect as a vote cast "AGAINST" the Merger Proposal.

        The KYTHERA Board recommends a vote "FOR" the Merger Proposal.

Adjournment Proposal

        KYTHERA is asking its stockholders to approve the adjournment of the KYTHERA special meeting to another date and place if necessary or appropriate to solicit additional votes in favor of the Merger Proposal. The Amended and Restated Merger Agreement provides that KYTHERA may not postpone or adjourn the KYTHERA special meeting for more than 30 days after the date on which the KYTHERA special meeting was originally scheduled.

        Completion of the Merger is not conditioned on the approval of the Adjournment Proposal.

Vote Required and KYTHERA Board Recommendation

        Assuming a quorum is present, the affirmative vote of at least a majority of the votes cast with respect to shares of KYTHERA common stock at the KYTHERA special meeting is required to approve the Adjournment Proposal. Abstentions and broker non-votes will have no effect on the outcome of this proposal.

        The KYTHERA Board recommends a vote "FOR" the Adjournment Proposal.

Merger-Related Named Executive Officer Compensation Proposal

        Pursuant to the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 and Rule 14a-21(c) of the Exchange Act, KYTHERA is seeking non-binding, advisory stockholder approval of the compensation to be paid to KYTHERA's named executive officers that is based on or otherwise relates to the Merger as disclosed in the section entitled "The Merger—Interests of KYTHERA's Directors and Executive Officers in the Merger—Quantification of Payments and Benefits to KYTHERA's Named Executive Officers" beginning on page 78 of this proxy statement. The proposal gives KYTHERA's

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stockholders the opportunity to express their views on the merger-related compensation of KYTHERA's named executive officers. Accordingly, KYTHERA is requesting stockholders to adopt the following resolution, on a non-binding, advisory basis:

        "RESOLVED, that the compensation that may be paid or become payable to KYTHERA's named executive officers in connection with the Merger, as disclosed pursuant to Item 402(t) of Regulation S-K in "The Merger—Interests of KYTHERA's Directors and Executive Officers in the Merger—Quantification of Payments and Benefits to KYTHERA's Named Executive Officers," is hereby APPROVED."

        Completion of the Merger is not conditioned on approval of the Merger-Related Named Executive Officer Compensation Proposal.

Vote Required and KYTHERA Board Recommendation

        The vote on this proposal is a vote separate and apart from the vote to approve the Merger Proposal. Accordingly, you may vote not to approve the Merger-Related Named Executive Officer Compensation Proposal and vote to approve the Merger Proposal or vice versa. The KYTHERA stockholders' vote regarding the Merger-Related Named Executive Officer Compensation Proposal is an advisory vote, and therefore is not binding on KYTHERA or the KYTHERA Board or the compensation committee of KYTHERA. Since compensation and benefits to be paid or provided in connection with the Merger are based on contractual arrangements with the named executive officers, the outcome of this advisory vote will not affect the obligation to make these payments and these payments may still be made even if the KYTHERA stockholders do not approve, by advisory (non-binding) vote, the Merger-Related Named Executive Officer Compensation Proposal.

        Assuming a quorum is present, the affirmative vote of a majority of the votes cast with respect to shares of KYTHERA common stock at the KYTHERA special meeting is required to approve the Merger-Related Named Executive Officer Compensation Proposal. Abstentions and broker non-votes will have no effect on the outcome of this proposal.

        The KYTHERA Board recommends a vote "FOR" the Merger-Related Named Executive Officer Compensation Proposal.

Other Matters to Come Before the KYTHERA Special Meeting

        As of the date of this proxy statement, the KYTHERA Board is not aware of any matters that will be presented for consideration at the KYTHERA special meeting other than as described in this proxy statement. If, however, the KYTHERA Board properly brings any other matters before the KYTHERA special meeting, the persons named in the proxy will vote the shares represented thereby in accordance with the recommendation of the KYTHERA Board on any such matter (unless the KYTHERA stockholder checks the box on the proxy card to withhold discretionary voting authority).

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PARTIES INVOLVED IN THE MERGER

Allergan

Allergan plc
Clonshaugh Business and Technology Park
Coolock, Dublin, D17 E400, Ireland
Phone: (862) 261-7000

        Allergan plc (formerly known as Actavis plc) was incorporated in Ireland as Actavis Limited on May 16, 2013 as a private limited company and re-registered effective September 18, 2013 as a public limited company. On June 15, 2015, the Company changed its name from Actavis plc to Allergan plc, following the acquisition of Legacy Allergan by Actavis plc in March 2015 and the approval of the name change by Actavis plc's shareholders. Allergan is a unique, global pharmaceutical company and a leader in a new industry model—Growth Pharma. Allergan is focused on developing, manufacturing and commercializing innovative branded pharmaceuticals, high-quality generic and over-the-counter medicines and biologic products for patients around the world. Allergan markets a portfolio of best-in-class products that provide valuable treatments for the central nervous system, eye care, medical aesthetics, gastroenterology, women's health, urology, cardiovascular and anti-infective therapeutic categories, and operates the world's third-largest global generics business, providing patients around the globe with increased access to affordable, high-quality medicines. Allergan is an industry leader in research and development, with one of the broadest development pipelines in the pharmaceutical industry and a leading position in the submission of generic product applications globally. With commercial operations in approximately 100 countries, Allergan is committed to working with physicians, healthcare providers and patients to deliver innovative and meaningful treatments that help people around the world live longer, healthier lives.

Merger Sub

Keto Merger Sub, Inc.
c/o Allergan plc
Morris Corporate Center III
400 Interpace Parkway
Parsippany, New Jersey 07054
Phone: (862) 261-7000

        Merger Sub is a Delaware corporation and an indirect wholly owned subsidiary of Allergan. Merger Sub was incorporated on May 28, 2015 for the sole purpose of effecting the Merger. As of the date of this proxy statement, Merger Sub has not conducted any activities other than those incidental to its formation, the execution of the Amended and Restated Merger Agreement, the preparation of applicable filings under U.S. securities laws and regulatory filings made in connection with the proposed transaction.

KYTHERA

KYTHERA Biopharmaceuticals, Inc.
30930 Russell Ranch Road, 3rd floor
Westlake Village, CA 91362
Phone: (818) 587-4500

        KYTHERA is a biopharmaceutical company focused on the discovery, development and commercialization of novel prescription products for the aesthetic medicine market. KYTHERA's objective is to develop first-in-class, prescription products using an approach that relies on the scientific rigor of biotechnology to address unmet needs in the rapidly-growing market for aesthetic medicine.

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KYTHERA's initial focus is on the facial aesthetics market, which comprises the majority of the aesthetic medicine market. On April 29, 2015, the U.S. Food and Drug Administration approved KYTHERA's first product KYBELLA™, a non-surgical treatment for the reduction of submental fullness, a common yet under-treated aesthetic condition, which commonly presents as an undesirable "double chin." KYTHERA was incorporated in Delaware in June 2004 under the name Dermion, Inc. KYTHERA commenced operations in August 2005 and later changed its name to AESTHERx, Inc. In July 2006, it changed its name to KYTHERA Biopharmaceuticals, Inc.

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THE MERGER

        This discussion of the Merger is qualified in its entirety by reference to the Amended and Restated Merger Agreement, which is attached to this proxy statement as Annex A and is incorporated by reference into this proxy statement. This summary does not purport to be complete and may not contain all of the information about the Merger that is important to you. You should read the entire Amended and Restated Merger Agreement carefully as it is the legal document that governs the Merger. This section is not intended to provide you with any factual information about Allergan or KYTHERA. Such information can be found elsewhere in this proxy statement and in the public filings KYTHERA makes with the SEC that are incorporated by reference into this proxy statement, as described in the section entitled "Where You Can Find More Information" beginning on page 127 of this proxy statement.

Transaction Structure

        Pursuant to the Amended and Restated Merger Agreement, Merger Sub will merge with and into KYTHERA, with KYTHERA continuing as the Surviving Corporation. Following the Merger, KYTHERA will be an indirect wholly owned subsidiary of Allergan and the KYTHERA common stock will be delisted from NASDAQ, deregistered under the Exchange Act and cease to be publicly traded.

Consideration to KYTHERA Stockholders

        As a result of the Merger, each issued and outstanding share of KYTHERA common stock, other than excluded shares and dissenting shares, will be converted into the right to receive the Merger Consideration.

        The Merger Consideration will be adjusted appropriately to reflect the effect of any stock split, reverse stock split, stock dividend (including any dividend or distribution of securities convertible into KYTHERA common stock), reorganization, recapitalization, reclassification, combination, exchange of shares or other like change with respect to the shares of KYTHERA common stock outstanding after the date of the Amended and Restated Merger Agreement and prior to the effective time of the Merger.

Background of the Merger

        The KYTHERA Board, and KYTHERA's senior management, in their ongoing effort to maximize stockholder value, have periodically reviewed and assessed KYTHERA's business strategy, the various trends and conditions affecting its industry and its business generally and a variety of strategic alternatives, including a sale of KYTHERA and distribution and collaboration arrangements with respect to KYTHERA's product and product candidate.

        In mid-2012, at the direction of the KYTHERA Board, and as part of the KYTHERA Board's consideration of an initial public offering process, Keith Leonard, KYTHERA's Chief Executive Officer, had informal discussions with David Pyott, then the Chairman of the Board of Directors and Chief Executive Officer of Legacy Allergan, and with one other large multinational pharmaceutical company regarding their potential interest in a strategic acquisition of KYTHERA. After several discussions, Mr. Pyott verbally informed Mr. Leonard that Legacy Allergan was interested in an acquisition of KYTHERA and submitted an oral non-binding proposal to acquire KYTHERA for approximately $225 million in cash plus potential future milestone payments. After discussion with the KYTHERA Board, KYTHERA declined Legacy Allergan's proposal. KYTHERA announced the closing of its initial public offering on October 16, 2012.

        In early 2014, the KYTHERA Board determined to re-acquire the rights to develop and commercialize its primary product, ATX-101 (deoxycholic acid), outside of the United States and Canada (ATX-101 is now known as KYBELLA™ in the United States) from Bayer Consumer Care AG

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(referred to in this proxy statement as "Bayer"), KYTHERA's then collaboration partner. KYTHERA initially entered into a collaboration arrangement with Bayer for the development and commercialization of ATX-101 outside the United States and Canada in 2010. The KYTHERA Board determined to re-acquire the rights to develop and commercialize ATX-101 outside of the United States and Canada because the KYTHERA Board believed that those rights could be acquired from Bayer for significantly less than their long term value to KYTHERA, and because the KYTHERA Board believed that KYTHERA would be able to enter into a collaboration agreement in the future regarding the rights to develop and commercialize ATX-101 outside of the United States and Canada on more favorable terms. KYTHERA announced the re-acquisition of the rights to develop and commercialize ATX-101 outside of the United States and Canada from Bayer in March 2014.

        Beginning in March 2014, at the direction of the KYTHERA Board, KYTHERA contacted approximately thirty (30) pharmaceutical and biotechnology companies about potential collaborations with KYTHERA in the distribution of ATX-101 in various countries or regions outside of the United States, and KYTHERA entered into confidentiality agreements with eleven (11) of those parties in connection with distribution discussions, none of which included a standstill provision. Legacy Allergan was one of the parties that KYTHERA contacted in March 2014. KYTHERA and Legacy Allergan entered into a confidentiality agreement (which did not include a standstill provision) on October 13, 2014 in connection with a potential distribution relationship outside of the United States, and Legacy Allergan conducted due diligence on KYTHERA from October 13, 2014 until the consummation of the Legacy Allergan Transaction on March 17, 2015, and from and after the consummation of the Legacy Allergan Transaction, Allergan conducted due diligence, in each case, relating to the potential distribution relationship. In addition, between October 13, 2014 and April 1, 2015 members of senior management of KYTHERA and representatives of Legacy Allergan and, from and after the consummation of the Legacy Allergan Transaction, representatives of Allergan discussed the potential terms of a distribution agreement outside of the United States both on telephone calls and in person. Those discussions did not include any discussion of a potential acquisition of KYTHERA by Legacy Allergan or by Allergan.

        Legacy Allergan announced that it was being acquired by Allergan (then Actavis plc) on November 17, 2014. Discussions and due diligence regarding a potential distribution agreement with respect to ATX-101 outside of the United States continued during the pendency of the acquisition of Legacy Allergan by Allergan (then Actavis plc) and the acquisition of Legacy Allergan by Allergan (then Actavis plc) was completed on March 17, 2015. The last discussion between members of senior management of KYTHERA and members of senior management of Allergan regarding a potential distribution agreement with respect to ATX-101 outside of the United States occurred on April 1, 2015, with no further discussions or due diligence on such topic occurring since April 1, 2015 between members of senior management of KYTHERA and members of senior management of Allergan.

        In early 2014, and again in early 2015, as part of a regular annual review with the KYTHERA Board, members of the KYTHERA Board and members of KYTHERA's senior management discussed and considered KYTHERA's state of readiness to appropriately respond in the event of an unsolicited offer to acquire KYTHERA. Latham & Watkins LLP, KYTHERA's outside legal advisors (referred to in this proxy statement as "Latham & Watkins") also participated in these discussions. In early 2015, members of KYTHERA's senior management met with representatives of Goldman Sachs. After these meetings, KYTHERA senior management determined that Goldman Sachs was qualified to support KYTHERA should its services be required in assisting the KYTHERA Board in its evaluation of strategic alternatives or in connection with responding to an unsolicited offer because of Goldman Sachs' historical relationships and familiarity with KYTHERA and its business as well as Goldman Sachs' experience and expertise in the biotechnology and pharmaceutical industries generally and familiarity with participants in those industries along with Goldman Sachs' experience in merger and acquisition transactions. In March 2015, members of KYTHERA's senior management requested that

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Goldman Sachs begin to prepare for a discussion with the KYTHERA Board at its regularly scheduled meeting on June 2, 2015 regarding Goldman Sachs' preliminary financial analysis of KYTHERA and the possibility of an unsolicited offer to acquire KYTHERA. However, KYTHERA did not formally engage Goldman Sachs as KYTHERA's financial advisor with respect to a potential strategic transaction at this time.

        On March 23, 2015, Mr. Leonard was contacted over e-mail by Doug Ingram, Special Advisor to the Chief Executive Officer of Allergan and the former President of Legacy Allergan, about a potential meeting with Brenton L. Saunders, the President and Chief Executive Officer of Allergan. Mr. Ingram did not provide a reason for the meeting with Mr. Saunders.

        Mr. Ingram scheduled an in-person meeting between Mr. Leonard and Mr. Saunders on April 6, 2015, which was subsequently cancelled for personal reasons.

        Mr. Leonard and Mr. Saunders spoke over the telephone on April 8, 2015, and, during their conversation, Mr. Saunders inquired as to KYTHERA's long-term strategy and whether KYTHERA would be interested in a potential strategic transaction with Allergan. Mr. Leonard and Mr. Saunders did not discuss the potential price that Allergan would pay for KYTHERA or any of the other terms of a potential strategic transaction. Mr. Leonard agreed to raise the possibility of a strategic transaction with Allergan with other members of the KYTHERA Board and to respond to Mr. Saunders.

        Between April 8 and April 10, 2015, Mr. Leonard discussed a potential strategic transaction with Allergan with Hollings Renton, Michael Ball and Dennis Fenton, three other members of the KYTHERA Board, and, on April 14, 2015, Mr. Leonard again spoke with Mr. Saunders by telephone and indicated to Mr. Saunders that KYTHERA was not for sale at that time, but that the KYTHERA Board would review and consider any proposal that appropriately valued the potential for growth inherent in KYTHERA's business.

        On April 17, 2015, Mr. Saunders met with Mr. Leonard and indicated to Mr. Leonard that Allergan was enthusiastic about a potential acquisition of KYTHERA and that KYTHERA would complement Allergan's position in other segments of the aesthetics space. Mr. Leonard did not discuss with Mr. Saunders any potential price that Allergan would pay for KYTHERA or any other terms of a potential acquisition. Mr. Saunders indicated to Mr. Leonard that Allergan would be submitting a non-binding written proposal to acquire KYTHERA.

        On April 23, 2015, Mr. Saunders delivered to Mr. Leonard a written preliminary non-binding expression of interest in an acquisition of KYTHERA by Allergan at a price between $65.00 and $67.50 per share of KYTHERA common stock, 20% of which would be paid in cash with the remainder in Allergan ordinary shares. Mr. Saunders' letter noted that Allergan had offered the mix of 20% cash and 80% Allergan ordinary shares out of a desire to maintain an investment grade rating for Allergan and to provide the pro forma company with a strong balance sheet, that the mix of cash and stock was subject to change and that the stock portion of the consideration would be converted to a fixed exchange ratio prior to signing a definitive agreement. Mr. Saunders' letter also noted that Allergan anticipated that the cash portion of the consideration required for the transaction would be provided by a combination of existing cash and credit facilities at Allergan, that Allergan expected that the transaction would not be subject to any financing contingency, that Allergan would not participate in any auction of KYTHERA, and that the transaction would be subject only to customary closing conditions, including the receipt of necessary antitrust approvals, and would not require approval by Allergan's stockholders. The preliminary non-binding expression of interest received from Allergan did not include any other material terms. In a phone call on April 23, 2015, Mr. Saunders also expressed concern to Mr. Leonard about recent hires by KYTHERA of former Allergan employees.

        During the evening of April 23, 2015, the KYTHERA Board held a telephonic meeting and discussed the preliminary non-binding expression of interest that had been received from Allergan.

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Representatives from Latham & Watkins also attended the meeting. Following the discussion, the KYTHERA Board requested that Mr. Leonard contact Goldman Sachs and request that Goldman Sachs meet with the KYTHERA Board early the following week to provide its views on the preliminary non-binding expression of interest received from Allergan and present its preliminary financial analysis with respect to KYTHERA. The KYTHERA Board requested that members of KYTHERA's senior management contact Goldman Sachs because Goldman Sachs was already assisting KYTHERA in its preparation to respond to any unsolicited offer to acquire KYTHERA and was in the process of preparing a preliminary financial analysis of KYTHERA for review by the KYTHERA Board at its next regularly scheduled meeting on June 2, 2015. On April 25, 2015, Goldman Sachs confirmed its ability to act as financial advisor to KYTHERA in connection with a potential sale transaction.

        On April 27, 2015, as the KYTHERA Board had not yet reached a final determination regarding whether to affirmatively engage Goldman Sachs as KYTHERA's financial advisor in connection with a potential sale transaction, KYTHERA entered into an indemnification letter agreement with Goldman Sachs in order to provide the KYTHERA Board with additional time to further consider whether to formally engage Goldman Sachs while Goldman Sachs provided its views on the preliminary non-binding expression of interest received from Allergan and presented its preliminary financial analysis with respect to KYTHERA.

        The KYTHERA Board held another telephonic meeting on April 27, 2015, and discussed the preliminary non-binding expression of interest that had been received from Allergan with representatives from Goldman Sachs and Latham & Watkins and members of KYTHERA's senior management. During the meeting, representatives from Goldman Sachs reviewed its preliminary financial analysis with respect to KYTHERA. The KYTHERA Board discussed KYTHERA's current business plan and prospects, the anticipated receipt of approval from the U.S. Food and Drug Administration (referred to in this proxy statement as the "FDA") for KYBELLA™, and an appropriate response to Allergan. Following that discussion, the KYTHERA Board requested that Mr. Leonard respond to Allergan and indicate that KYTHERA was focused on preparations for the potential product launch of KYBELLA™ and committed to maximizing value for its stockholders, that Allergan's expression of interest significantly undervalued KYTHERA and the value that a combination with Allergan would create, and that KYTHERA was not prepared to engage in discussions with Allergan on the proposed terms. Mr. Leonard delivered KYTHERA's response to Allergan in writing and in a phone call to Mr. Saunders on April 29, 2015.

        On April 29, 2015, each of KYTHERA and the FDA separately announced that the FDA had approved KYBELLA™ for improvement in the appearance of moderate to severe convexity or fullness associated with submental fat in adults. KYBELLA™ is the first and only approved non-surgical treatment for reduction of submental fullness, a common yet under-treated aesthetic condition.

        On May 1, 2015, Mr. Saunders spoke with Mr. Leonard and subsequently delivered to Mr. Leonard a revised written preliminary non-binding expression of interest in an acquisition of KYTHERA by Allergan at a price between $67.50 and $72.50 per share of KYTHERA common stock, 20% of which would be paid in cash with the remainder in Allergan ordinary shares. The May 1, 2015 preliminary non-binding expression of interest from Allergan was otherwise consistent with the April 23, 2015 preliminary non-binding expression of interest from Allergan and did not contain any new material terms.

        The KYTHERA Board held a telephonic meeting on May 3, 2015 to consider the revised preliminary non-binding expression of interest that had been received from Allergan, and representatives from Goldman Sachs and Latham & Watkins and members of KYTHERA's senior management attended the meeting. Representatives from Goldman Sachs reviewed the terms of the revised Allergan offer relative to both the initial non-binding expression of interest received from Allergan and to its preliminary financial analysis with respect to KYTHERA. A discussion followed

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among the KYTHERA Board, the members of senior management and advisors regarding the preliminary financial analysis, KYTHERA's current business plan and prospects, the receipt of FDA approval for KYBELLA™, the terms of the revised non-binding expression of interest that had been received from Allergan and the appropriate response to Allergan. Following the discussion, the KYTHERA Board directed that Mr. Leonard again respond to Allergan and indicate that KYTHERA was focused on preparations for the product launch of KYBELLA™ and committed to maximizing value for its stockholders, that Allergan's expression of interest significantly undervalued KYTHERA and the value that a combination with Allergan would create, and that KYTHERA was not prepared to engage in discussions with Allergan on the proposed terms.

        Mr. Leonard delivered KYTHERA's response to Allergan in writing and in a phone call to Mr. Saunders on May 4, 2015. Mr. Saunders indicated to Mr. Leonard that Allergan was unlikely to be able to increase its proposal, but that it would continue to review and evaluate a potential acquisition of KYTHERA.

        On May 11, 2015, Mr. Saunders again spoke with Mr. Leonard by telephone and indicated that Allergan might be able to increase its non-binding expression of interest to the low-mid to high-mid $70's per share, but only if KYTHERA would grant Allergan access to certain limited due diligence information. No other material terms of a potential acquisition were discussed at that time. Mr. Saunders also expressed concern to Mr. Leonard about recent hires by KYTHERA of former Allergan employees, and noted that Allergan continued to consider instituting litigation against KYTHERA relating to those new hires and non-solicitation agreements that such former Allergan employees had entered into with Allergan.

        Later in the day on May 11, 2015, the KYTHERA Board held a telephonic meeting and discussed with representatives from Goldman Sachs and Latham & Watkins and members of KYTHERA's senior management Allergan's May 1, 2015 expression of interest, the possibility of an increased offer range from Allergan and the need to have a confidentiality agreement with a customary standstill in place with Allergan before permitting it to conduct any due diligence on KYTHERA, and the potential litigation related to former Allergan employees that had accepted employment offers with KYTHERA. Following the discussion, the KYTHERA Board directed Mr. Leonard to respond to Mr. Saunders and indicate that KYTHERA was prepared to permit Allergan to conduct limited due diligence on KYTHERA to support Allergan's evaluation of a potential increase to its expression of interest only if Mr. Saunders believed that Allergan could reach the high end of his previously stated range, that if any transaction were agreed to the KYTHERA Board would wish to deliver fixed value to KYTHERA's stockholders in the form of an all cash transaction, and that the ability to quickly reach a definitive agreement with respect to and subsequently complete any transaction was important to KYTHERA in light of the pending launch of KYBELLA™ and the potential for such a transaction to disrupt that launch. The KYTHERA Board also informed Mr. Leonard that a "two step" tender offer or exchange offer structure would be preferable to a "one step" merger structure, in light of the potential ability of the "two step" structure to reduce the amount of time between execution of the definitive transaction agreement and the consummation of the transaction and, therefore, increase the likelihood that the transaction would be consummated. The KYTHERA Board also directed Mr. Leonard to inform Mr. Saunders that the KYTHERA Board would not view any litigation commenced against KYTHERA by Allergan with respect to former Allergan employees favorably and that the KYTHERA Board and members of KYTHERA's senior management did not believe that the former Allergan employees had violated any agreements with Allergan.

        On May 12, 2015, Mr. Leonard spoke with Mr. Saunders by telephone and delivered KYTHERA's response. During this conversation, Mr. Saunders indicated that Allergan would not commence any litigation against KYTHERA related to KYTHERA's hiring of former Allergan employees pending resolution of the acquisition discussions. Later that day, KYTHERA delivered a draft confidentiality agreement to Allergan.

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        On May 14, 2015, KYTHERA and Allergan entered into a confidentiality agreement with respect to a potential acquisition of KYTHERA, which included a customary standstill provision that terminated upon the announcement of a merger or other business combination transaction involving KYTHERA.

        Between May 14, 2015 and May 25, 2015, members of KYTHERA's senior management team coordinated responses to Allergan's limited due diligence requests, and Allergan and its advisors conducted related due diligence on KYTHERA and its business.

        On May 25, 2015, Mr. Saunders spoke with Mr. Leonard over the telephone and indicated that Allergan had completed its limited additional due diligence activities and was prepared to increase its non-binding proposal to acquire KYTHERA to $73.50-$74.00 per share, and that the form of consideration would remain mixed, with 80% of the consideration to be paid in Allergan ordinary shares and 20% in cash, and that the transaction would be structured as a "one step" merger subject to approval by a vote of KYTHERA's stockholders and not as a "two step" exchange offer. Mr. Leonard responded to Mr. Saunders that a proposal representing per share consideration in the mid-to-high $70's would be viewed as a stronger proposal by the KYTHERA Board. Mr. Saunders again spoke with Mr. Leonard over the telephone later that day, and reported that Allergan was willing to further increase its non-binding proposal to $75.00 per share and that Allergan was not willing to increase its proposal above $75.00 per share.

        During the afternoon of May 25, 2015, Mr. Saunders delivered Mr. Leonard a revised written preliminary non-binding expression of interest in an acquisition of KYTHERA by Allergan at a price of $75.00 per share of KYTHERA common stock, 20% of which would be paid in cash with the remainder in Allergan ordinary shares. The May 25, 2015 preliminary non-binding expression of interest from Allergan was otherwise consistent with the May 1, 2015 preliminary non-binding expression of interest from Allergan, except that it no longer provided that the stock portion of the consideration would be converted to a fixed exchange ratio prior to signing a definitive agreement, and the May 25, 2015 preliminary non-binding expression of interest from Allergan did not contain any new material terms.

        The KYTHERA Board held a telephonic meeting later in the day on May 25, 2015, and discussed with representatives from Goldman Sachs and Latham & Watkins and members of KYTHERA's senior management the revised non-binding offer received from Allergan, including the mix of cash and stock consideration that had been proposed, whether or not the stock portion of the consideration would represent "fixed" value or contain a "collar", and the proposed transaction structure as a "one-step" merger rather than an exchange offer and the related timing of closing a transaction.

        The KYTHERA Board held another telephonic meeting on May 26, 2015 to further review the revised non-binding expression of interest received from Allergan. Representatives from Goldman Sachs and Latham & Watkins and members of KYTHERA's senior management also attended the meeting. Members of KYTHERA's senior management reviewed certain financial forecasts that had been prepared by members of KYTHERA's senior management with respect to KYTHERA and its business, as further described in the section entitled "—KYTHERA Unaudited Prospective Financial Information" beginning on page 65 of this proxy statement. Representatives from Goldman Sachs reviewed the terms of the Allergan expression of interest relative to its preliminary financial analysis with respect to KYTHERA. The KYTHERA Board discussed with members of KYTHERA's senior management and its advisors the preliminary financial analysis with respect to KYTHERA and the terms of the revised non-binding expression of interest received from Allergan, as well as potential responses to Allergan. The KYTHERA Board also noted that KYTHERA had not contacted any other potential acquirers and discussed the possibility of outreach to additional potential counterparties who might be interested in an acquisition of KYTHERA. Following that discussion, the KYTHERA Board determined that it believed the $75.00 per share offer received from Allergan was a fair price and that

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it was in the best interests of KYTHERA to further explore a potential transaction with Allergan, and directed Mr. Leonard to speak with Mr. Saunders in order to determine whether Allergan would be prepared to offer an all cash transaction on an accelerated timetable or whether Allergan would otherwise offer a fixed value transaction without any significant risk to KYTHERA stockholders resulting from fluctuations in Allergan's stock price prior to closing. The KYTHERA Board also requested that management work with the representatives from Goldman Sachs to prepare a list of potential additional counterparties to contact regarding a potential business combination transaction with, or acquisition of, KYTHERA for the KYTHERA Board to consider and to promptly begin outreach to those counterparties once the KYTHERA Board had determined such counterparties. The KYTHERA Board directed management to identify companies likely to have a high level of interest in an acquisition of KYTHERA that would reasonably be expected to have an ability to improve upon the terms of the expression of interest from Allergan and that would reasonably be expected to have a willingness to act decisively to negotiate and consummate a transaction.

        Additionally, at the May 26, 2015 meeting, as the third part of an ongoing overall assessment of change in control and severance terms for all employees of KYTHERA which commenced in January 2015 and was unrelated to any potential strategic transaction, the KYTHERA Board considered and approved certain revised severance terms for employees of KYTHERA at the level of Vice President and above, and directed management to implement the revised severance terms. The first category of the overall assessment of change in control and severance terms for KYTHERA employees occurred in January 2015, when the change in control and severance terms for potential new hires in the KYTHERA sales force were reviewed by the KYTHERA compensation committee and KYTHERA Board with a proviso from the KYTHERA Board that, if change in control protection was provided to the sales force, then KYTHERA management and the KYTHERA Board should consider changes for other employees. The second category of the overall assessment occurred in March 2015, when the change in control and severance terms for all employees at levels below Vice President were reviewed by the KYTHERA compensation committee and KYTHERA Board, with a proviso from the KYTHERA Board that the KYTHERA compensation committee and KYTHERA Board agreed to discuss, in the very near future, a review of change in control and severance terms for executive staff.

        The representatives of Goldman Sachs then left the May 26, 2015 meeting, and representatives from Latham & Watkins provided the members of the KYTHERA Board with an overview of their fiduciary duties to KYTHERA and its stockholders under Delaware law with respect to a potential transaction. The KYTHERA Board then considered the terms of an engagement letter with Goldman Sachs that had been negotiated between representatives of Goldman Sachs and members of KYTHERA's senior management team. Following discussion of retaining Goldman Sachs as KYTHERA's financial advisor and the engagement letter, the KYTHERA Board unanimously approved the engagement of Goldman Sachs and the Goldman Sachs engagement letter and directed management to finalize and execute the engagement letter on behalf of KYTHERA. Goldman Sachs was selected by the KYTHERA Board because of its historical relationships and familiarity with KYTHERA and its business as well as Goldman Sachs' experience and expertise in the biotechnology and pharmaceutical industries generally and familiarity with participants in those industries, along with Goldman Sachs' experience in mergers and acquisitions transactions. The KYTHERA Board also considered the fact that Goldman Sachs had acted as financial advisor to Legacy Allergan in connection with the Legacy Allergan Transaction, which was consummated on March 17, 2015.

        Later on May 26, 2015, Mr. Leonard spoke with Mr. Saunders by telephone and informed Mr. Saunders that KYTHERA would be interested in exploring a potential transaction with Allergan. Mr. Leonard and Mr. Saunders also discussed the possibility of an all cash acquisition and the timing of the consummation of a potential transaction. Mr. Saunders agreed in principle that the consideration payable in an acquisition of KYTHERA could be "fixed" in value, but did not agree to move to all cash consideration.

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        Goldman Sachs and KYTHERA executed an engagement letter on May 27, 2015 with respect to Goldman Sachs acting as financial advisor to KYTHERA concerning a possible sale of KYTHERA.

        On May 27, 2015, members of KYTHERA's senior management and representatives of Goldman Sachs discussed companies that might be contacted by Goldman Sachs regarding a potential acquisition of KYTHERA. The members of KYTHERA's senior management ultimately determined, after consultation with Goldman Sachs, that there were five potential strategic counterparties which could have a high level of interest in a business combination with, or acquisition of, KYTHERA, that would reasonably be expected to have an ability to improve upon the terms of the expression of interest from Allergan and that would reasonably be expected to have a willingness to act decisively to negotiate and consummate a transaction. Mr. Leonard then contacted each of the other members of the KYTHERA Board, reviewed the five potential strategic counterparties to be contacted by Goldman Sachs with each of them, and confirmed that the other members of the KYTHERA Board did not have any additional potential counterparties that they believed should be contacted by Goldman Sachs. Following discussion with the KYTHERA Board, Mr. Leonard advised Goldman Sachs that it should begin its outreach to each of the five potential strategic counterparties described above to identify the level of interest such potential strategic counterparties would have in a potential business combination with, or acquisition of, KYTHERA.

        Goldman Sachs contacted all five of the potential counterparties during the two-day period from May 28 through May 29, 2015 and inquired as to each of their interest in a potential strategic transaction involving KYTHERA at a valuation above the mid-point of the $70's per share. Between May 28 and June 2, 2015 each of the five potential counterparties responded to Goldman Sachs and indicated that it was not interested in pursuing a business combination with, or acquisition of, KYTHERA. The five potential counterparties did not otherwise provide specific reasons for not pursuing an acquisition of KYTHERA.

        On May 28, 2015, Latham & Watkins received a due diligence request list from Covington & Burling LLP, legal counsel to Allergan in connection with the potential acquisition of KYTHERA, (referred to in this proxy statement as "Covington & Burling"). Members of KYTHERA's senior management team coordinated responses to the diligence requests, and Allergan and its representatives continued to conduct due diligence with respect to KYTHERA between May 28, 2015 and June 16, 2015 and participated in due diligence conference calls with members of senior management of KYTHERA and KYTHERA's representatives. In addition, during that same period of time, KYTHERA and its representatives conducted due diligence with respect to Allergan and its ordinary shares.

        Also on May 28, 2015, Latham & Watkins received a draft Initial Merger Agreement from Covington & Burling in connection with the potential acquisition of KYTHERA by Allergan, as well as a draft Initial Voting Agreement which Allergan requested that each member of the KYTHERA Board and each of KYTHERA's officers sign as a condition to Allergan's willingness to enter into a potential transaction.

        On June 1, 2015, based on input from KYTHERA, Latham & Watkins sent a revised draft Initial Merger Agreement to Covington & Burling, and, later in the day on June 1, 2015, representatives of Latham & Watkins and Covington & Burling discussed the principal issues raised by the draft Initial Merger Agreement.

        Between June 1, 2015 and June 14, 2015, based on input from their respective clients, representatives of Latham & Watkins and Covington & Burling exchanged drafts of the Initial Merger Agreement and negotiated the principal issues raised by the draft Initial Merger Agreement, including, among others, the form and mix of cash and share consideration that would be paid by Allergan, the structure and timing for completing a transaction, whether the Allergan share portion of the consideration would be subject to a collar limiting the maximum and minimum number of Allergan

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ordinary shares that might be issued to KYTHERA stockholders in a transaction or whether the share portion would have a fixed value, the appropriate measurement for valuing Allergan ordinary shares to be issued as consideration, the potential treatment of the transaction as a tax free reorganization if 80% of the consideration were to be in the form of Allergan ordinary shares, the scope of the parties' representations and warranties, conditions to closing a transaction and related risks and obligations, including the definition of a material adverse effect and obligations of the parties with respect to obtaining regulatory approvals, the parties' termination rights, and restrictions on KYTHERA's ability to solicit alternative transactions and on the ability of the KYTHERA Board to change its recommendation of the Merger and exceptions to those restrictions, as well as related obligations and amounts payable in connection with a termination of the Initial Merger Agreement in connection with a competing offer or following a change in recommendation. During that same time, Latham & Watkins and Covington & Burling, based on input from their respective clients, also negotiated the terms of the draft Initial Voting Agreement.

        The KYTHERA Board held a regularly scheduled meeting on June 2, 2015, following KYTHERA's 2015 annual meeting of stockholders. Representatives from Goldman Sachs and Latham & Watkins and members of KYTHERA's senior management attended the meeting.

        At the June 2, 2015 in-person meeting, Mr. Leonard and Goldman Sachs reviewed the results of the outreach to the five potential strategic counterparties. The KYTHERA Board considered the parties that had been contacted and the responses received and discussed with the members of management and advisors present whether to contact any additional potential counterparties regarding a business combination with, or acquisition of, KYTHERA and, following such discussion, the KYTHERA Board determined not to contact any additional counterparties at that time. The KYTHERA Board made its determination not to contact any additional counterparties in light of the KYTHERA Board's knowledge and experience in the aesthetics market and with participants in the health care industry generally and because Goldman Sachs had already contacted all of the potential strategic counterparties which the KYTHERA Board believed were likely to be interested in a potential business combination with, or acquisition of, KYTHERA or its products and which would be able to act decisively to negotiate and consummate a transaction and the results of that outreach. The KYTHERA Board determined not to contact any potential financial buyers, as it believed that financial buyers would not be willing to pay as high of a price as Allergan or other potential strategic counterparties due to the inherent uncertainty around the implementation of a successful launch of KYBELLA™ and due to the synergies that strategic counterparties would expect to be able to realize through a business combination with, or acquisition of, KYTHERA. The KYTHERA Board also considered the possibility of initiating an auction process to sell KYTHERA and determined that it did not believe an auction of KYTHERA would be in the best interests of KYTHERA or its stockholders given the premium offer that had been made by Allergan, the fact that Allergan had indicated in its non-binding expressions of interest that Allergan would not participate in any auction of KYTHERA, the pending launch of KYTHERA's first consumer product, KYBELLA™, the distraction that an auction would represent to management, and concerns that any further outreach to counterparties with respect to a potential business combination with, or acquisition of, KYTHERA could result in public disclosure or market rumors regarding the fact that KYTHERA was considering a potential strategic transaction which could result in premature speculation about the future of KYTHERA, which, in turn, could severely hamper the launch of KYBELLA™ and jeopardize the morale and effectiveness of KYTHERA's employees, as well as other potentially adverse consequences. In addition, the KYTHERA Board considered KYTHERA's intent to retain flexibility to consider a superior offer following announcement of a sale of KYTHERA even if a definitive agreement were reached with Allergan.

        Representatives of Goldman Sachs then reviewed with the KYTHERA Board management's probability adjusted revenue forecasts and profit and loss forecasts, as well as certain assumptions underlying management's forecasts, as further described in the section entitled "—KYTHERA Unaudited

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Prospective Financial Information" beginning on page 65 of this proxy statement, and the terms of the current Allergan proposal to acquire KYTHERA relative to Goldman Sachs' preliminary financial analysis with respect to KYTHERA. Goldman Sachs also advised the KYTHERA Board that during the two-year period ended June 2, 2015, Goldman Sachs' investment banking division had not provided any financial advisory and/or underwriting services for Allergan (formerly Actavis plc) or its affiliates for which it received compensation. Representatives from Latham & Watkins also reviewed with the KYTHERA Board the principal terms of the draft Initial Merger Agreement and draft Initial Voting Agreement that had been received from Allergan as well as KYTHERA's initial response, and the KYTHERA Board discussed the Allergan proposal and the terms of the draft Initial Merger Agreement and draft Initial Voting Agreement, including the possibility of an all cash transaction on an expedited time frame or a fixed value transaction consisting of cash and a fixed value of Allergan ordinary shares per share of KYTHERA common stock and whether the Allergan ordinary share portion of the consideration would be subject to a collar or floor.

        On June 4, 2015, representatives of Allergan informed representatives of KYTHERA that Allergan would be approaching certain credit rating agencies to discuss alternative transaction structures for an acquisition of KYTHERA by Allergan. KYTHERA and Allergan entered into an amendment to their confidentiality agreement on June 9, 2015 in order to permit Allergan to discuss a potential acquisition of KYTHERA with the credit rating agencies.

        On June 12, 2015, following Allergan's discussions with the credit rating agencies, Mr. Saunders and Mr. Leonard met in person during a conference, and Mr. Saunders informed Mr. Leonard that Allergan would agree to pay the $75.00 per share consideration to acquire KYTHERA in a mix of 80% cash and 20% Allergan ordinary shares (rather than the mix of 20% cash and 80% Allergan ordinary shares that had been previously proposed) using a fixed value of Allergan ordinary shares determined based on a 10-day trailing volume weighted average price at the closing of a transaction, and without using a collar or a floor on the number of ordinary shares that Allergan might be required to issue. Mr. Saunders also informed Mr. Leonard that Allergan was not prepared to pursue an all cash transaction to KYTHERA.

        On June 14, 2015, members of KYTHERA's senior management spoke with members of the senior management of Allergan regarding the terms of the potential acquisition of KYTHERA by Allergan, including the proposed treatment of outstanding KYTHERA equity awards in an acquisition and the relation of that treatment to employee retention, and the parties' current positions with respect to their obligations to agree to certain divestitures or other limitations on their businesses and related requirements in connection with obtaining regulatory approvals for a transaction.

        Later in the day on June 14, 2015, the KYTHERA Board met telephonically with representatives from Goldman Sachs and Latham & Watkins and members of KYTHERA's senior management, and received an update from members of KYTHERA's senior management team regarding the potential transaction with Allergan, including the revised mix of consideration of 80% cash and 20% Allergan ordinary shares that had been proposed by Allergan. Mr. Leonard summarized the conversation that had taken place between members of KYTHERA's senior management and members of senior management of Allergan earlier that day.

        Representatives from Latham & Watkins next reviewed with the KYTHERA Board the principal terms of the Initial Merger Agreement and related Initial Voting Agreement being negotiated with Allergan, and discussed with the KYTHERA Board the negotiations with respect to the principal terms of the Initial Merger Agreement and related Initial Voting Agreement that had taken place since the June 2, 2015 meeting of the KYTHERA Board. The KYTHERA Board discussed with the members of senior management and its advisors present Allergan and its business as well as Allergan's ability to pay the cash portion of the proposed consideration. Following these discussions, the KYTHERA Board authorized its advisors to negotiate the final terms of the definitive Initial Merger Agreement and

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related documents with Allergan and its advisors with a goal of presenting final agreements to the KYTHERA Board for its consideration on the evening of June 16, 2015.

        Between June 14 and June 16, 2015, based on input from their respective clients, representatives of Latham & Watkins and Covington & Burling negotiated the remaining terms of, and finalized, the Initial Merger Agreement (pending approval by the KYTHERA Board) and the Initial Voting Agreement.

        On the evening of June 16, 2015, the KYTHERA Board met telephonically to consider the definitive Initial Merger Agreement and a potential acquisition of KYTHERA by Allergan and related matters. Representatives from Goldman Sachs and Latham & Watkins and members of KYTHERA's senior management attended the meeting. At the meeting, Mr. Leonard summarized recent negotiations with Allergan, and members of senior management summarized, for the KYTHERA Board, the takeaways from the due diligence discussions that members of KYTHERA's senior management had with members of senior management of Allergan regarding Allergan and its business. Representatives from Latham & Watkins reviewed with the KYTHERA Board the terms of the definitive Initial Merger Agreement with Allergan and the related Initial Voting Agreement, including changes to the terms of the Initial Merger Agreement and Initial Voting Agreement since the June 14, 2015 meeting of the KYTHERA Board. Representatives from Latham & Watkins also reviewed for the members of the KYTHERA Board their fiduciary duties to KYTHERA and its stockholders under Delaware law in connection with a sale of KYTHERA and a decision to enter into the Initial Merger Agreement. Representatives of Goldman Sachs next reviewed with the KYTHERA Board Goldman Sachs' financial analysis of the Initial Merger Consideration. Following discussion, representatives of Goldman Sachs then rendered to the KYTHERA Board the oral opinion of Goldman Sachs, which was subsequently confirmed by delivery of a written opinion dated as of June 17, 2015 and based upon and subject to the factors and assumptions set forth therein, that the consideration to be paid to the holders of outstanding shares of KYTHERA common stock (other than Allergan and its affiliates) pursuant to the Initial Merger Agreement was fair from a financial point of view to those holders. See the section entitled "—Opinion of Financial Advisor to KYTHERA" beginning on page 60 of this proxy statement.

        At the June 16, 2015 meeting, following further discussion, and after consultation with the members of senior management present and the representatives from Goldman Sachs and Latham & Watkins, the KYTHERA Board unanimously:

•

determined that the Initial Merger Agreement and the transactions contemplated thereby, including the Merger, were advisable, fair to, and in the best interests of, KYTHERA and its stockholders;



•

approved and declared advisable the Initial Merger Agreement and the transactions contemplated thereby, including the Merger, on the terms and subject to the conditions set forth in the Initial Merger Agreement;



•

resolved to recommend that KYTHERA's stockholders approve the adoption of the Initial Merger Agreement; and



•

authorized and approved the execution, delivery and performance of the Initial Merger Agreement by KYTHERA.

        On June 16, 2015, the KYTHERA Board also:

•

adopted a Retention Plan to establish a retention bonus pool in order to create incentives for each regular full-time employee of KYTHERA who is selected to participate in the Retention Plan by the administrator of the Retention Plan to continue their employment with KYTHERA through the closing of the Merger,

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•

approved an amendment to KYTHERA's 2015 Annual Incentive Plan, pursuant to which KYTHERA awards cash bonuses to employees based upon the attainment of certain performance goals, in order to clarify that under the 2015 Annual Incentive Plan, in the event a participant in the 2015 Annual Incentive Plan becomes entitled to receive severance following the closing of the Merger, such participant will be entitled to receive a pro-rata bonus payment for 2015 (or full bonus payment if such termination occurs after December 31, 2015 but before 2015 bonuses are paid); and



•

approved an amendment to the vesting schedules of the KYTHERA Stock Options and KYTHERA RSU Awards outstanding as of June 16, 2015 in order to create an incentive for KYTHERA's employees to continue their employment with KYTHERA through a change in control, including the Merger, and ensure that such employees are treated equitably after the change in control.

        Early in the morning on June 17, 2015, KYTHERA, Allergan and Merger Sub executed the Initial Merger Agreement, and KYTHERA and Allergan announced the transaction in a joint press release issued prior to the open of the markets on June 17, 2015.

        On the evening of June 30, 2015, the KYTHERA Board met telephonically to consider Amendment No. 1 to the Initial Merger Agreement in order to make a technical correction to the definition of "VWAP of Parent" included in the Initial Merger Agreement. Representatives from Goldman Sachs and Latham & Watkins and members of KYTHERA's senior management attended the meeting. At the meeting, representatives from Latham & Watkins summarized the proposed Amendment No. 1 to the Initial Merger Agreement, and representatives from Goldman Sachs advised the KYTHERA Board orally, which advice was confirmed in writing on July 1, 2015, that, based upon and subject to the factors and assumptions stated therein, had Goldman Sachs issued its opinion on June 17, 2015 on the basis of the transactions contemplated by the Initial Merger Agreement as amended by the proposed Amendment No. 1, the conclusion set forth in its opinion would not have changed.

        At the June 30, 2015 meeting, following further discussion, and after consultation with the members of senior management and the representatives from Goldman Sachs and Latham & Watkins present, the KYTHERA Board unanimously:

•

determined that the Initial Merger Agreement as amended by Amendment No. 1, and the transactions contemplated thereby, including the Merger, were advisable, fair to, and in the best interests of, KYTHERA and its stockholders;



•

approved and declared advisable the Initial Merger Agreement as amended by Amendment No. 1, and the transactions contemplated thereby, including the Merger, on the terms and subject to the conditions set forth in the Initial Merger Agreement as amended by Amendment No. 1;



•

resolved to recommend that KYTHERA's stockholders approve the adoption of the Initial Merger Agreement, as amended by Amendment No. 1; and



•

authorized and approved the execution, delivery and performance of Amendment No. 1.

        On the morning of July 1, 2015, KYTHERA, Allergan and Merger Sub executed Amendment No. 1.

        On July 6, 2015, each of KYTHERA and Allergan filed a Pre-Merger Notification and Report Form pursuant to the HSR Act with the Antitrust Division of the U.S. Department of Justice (referred to in this proxy statement as the "Antitrust Division") and the FTC.

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        On July 17, 2015, in accordance with the Initial Merger Agreement, as amended by Amendment No. 1, Allergan filed a registration statement on Form S-4 with respect to the Allergan ordinary shares that were to be issued in the Merger, with such registration statement also including a preliminary proxy statement with respect to a special meeting of the KYTHERA stockholder to vote on the adoption of the Initial Merger Agreement, as amended by Amendment No. 1, and related matters and a prospectus with respect to those Allergan ordinary shares being offered to KYTHERA stockholders pursuant to the Initial Merger Agreement, as amended by Amendment No. 1.

        On July 27, 2015, Allergan announced the execution of a Master Purchase Agreement entered into by and between Allergan and Teva Pharmaceutical Industries Ltd. (referred to in this proxy statement as "Teva"), dated as of July 26, 2015 (referred to in this proxy statement as the "Allergan-Teva Purchase Agreement"), pursuant to which, following the satisfaction or waiver of certain conditions, Teva will purchase the global generics business and certain other assets of Allergan (referred to in this proxy statement as the "Business"), including all of the equity interests of certain Allergan subsidiaries and all of the assets, property and rights of Allergan and its affiliates that are primarily related to or used primarily in connection with the global generics business and certain other assets of Allergan, for a cash purchase price of $33.75 billion, and $6.75 billion in unregistered restricted ordinary shares (or American Depository Shares with respect thereto) of Teva.

        Later in the day on July 27, 2015, Sigurd Kirk, Executive Vice President of Corporate Business Development at Allergan, telephoned Mr. Leonard and proposed to Mr. Leonard that Allergan and KYTHERA amend and restate the Initial Merger Agreement, as amended by Amendment No. 1, to change the form of consideration payable to KYTHERA stockholders in the Merger from $75.00 in fixed value, payable in a mix of 80% cash and 20% Allergan ordinary shares, to $75.00 payable in all cash. Mr. Kirk stated to Mr. Leonard that he believed that, structured as an all cash transaction, a transaction could be completed more quickly than the transaction provided for under the terms of the Initial Merger Agreement, as amended by Amendment No. 1. Mr. Leonard told Mr. Kirk that he would discuss the proposal with representatives of Latham & Watkins and the KYTHERA Board and would get back to him soon.

        Further consultation with Latham & Watkins and Covington & Burling revealed that, as a result of Allergan's entry into the Allergan-Teva Purchase Agreement, Allergan would be required under applicable securities laws to prepare and file with the SEC certain unaudited pro forma financial information reflecting the probable disposition of the Business to Teva pursuant to the Allergan-Teva Purchase Agreement (the "Allergan-Teva unaudited pro forma financial information") prior to the registration statement on Form S-4 becoming effective with respect to the stock portion of the Initial Merger Consideration to be issued to KYTHERA stockholders under the terms of the Initial Merger Agreement, as amended by Amendment No. 1. Furthermore, such Allergan-Teva unaudited pro forma financial information would take considerable time to prepare. However, structuring the transaction as an all cash transaction would permit KYTHERA to solicit proxies for a vote of its stockholders with respect to the adoption of such an Amended and Restated Merger Agreement without the need to wait for Allergan to prepare and file the Allergan-Teva unaudited pro forma financial information.

        In addition, on July 27, 2015, KYTHERA and Allergan issued a joint press release announcing that the FTC granted early termination of the associated waiting period under the HSR Act.

        On July 30, 2015, representatives of Covington & Burling provided a draft of the Amended and Restated Merger Agreement to representatives of Latham & Watkins reflecting consideration of $75.00 per share payable entirely in cash, as well as a draft Amended and Restated Voting Agreement. Between July 30, 2015 and August 3, 2015, based on input from KYTHERA and Allergan, respectively, representatives of Latham & Watkins and Covington & Burling finalized the Amended and Restated Merger Agreement (pending approval by the KYTHERA Board) and the Amended and Restated Voting Agreement.

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        On July 31, 2015, Mr. Leonard spoke with Mr. Saunders and indicated that KYTHERA was receptive to the amendment and restatement of the Initial Merger Agreement as amended by Amendment No. 1, and that such amendment and restatement would be proposed to the KYTHERA Board for their approval.

        On the evening of August 3, 2015, the KYTHERA Board met telephonically to consider the Amended and Restated Merger Agreement and the proposal from Allergan to amend the terms of the Initial Merger Agreement, as amended by Amendment No. 1, to reflect, among other things, consideration to be received by KYTHERA stockholders in the Merger of $75.00 per share of KYTHERA common stock in cash, without interest, as opposed to $75.00 per share of KYTHERA common stock consisting of 80% payable in cash and 20% payable in Allergan ordinary shares. Representatives from Goldman Sachs and Latham & Watkins and members of KYTHERA's senior management attended the meeting. At the meeting, representatives from Latham & Watkins summarized the proposed Amended and Restated Merger Agreement and also reviewed for the members of the KYTHERA Board their fiduciary duties to KYTHERA and its stockholders under Delaware law in connection with a decision to enter into the Amended and Restated Merger Agreement. Also at the meeting, representatives from Goldman Sachs advised the KYTHERA Board orally, which advice was confirmed in writing on August 4, 2015, that, based upon and subject to the factors and assumptions stated therein, had Goldman Sachs issued its opinion on June 17, 2015 on the basis of the transactions contemplated by the Amended and Restated Merger Agreement, the conclusion set forth in its opinion (with references to "Consideration" therein deemed to be $75.00 in cash per outstanding share of KYTHERA common stock) would not have changed.

        At the August 3, 2015 meeting, following further discussion, and after consultation with the members of senior management and the representatives from Goldman Sachs and Latham & Watkins present, the KYTHERA Board by the vote of all directors present:

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determined that the Amended and Restated Merger Agreement, and the transactions contemplated thereby, including the Merger, were advisable, fair to, and in the best interests of, KYTHERA and its stockholders;



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approved and declared advisable the Amended and Restated Merger Agreement, and the transactions contemplated thereby, including the Merger, on the terms and subject to the conditions set forth in the Amended and Restated Merger Agreement;



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resolved to recommend that KYTHERA's stockholders approve the adoption of the Amended and Restated Merger Agreement; and



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authorized and approved the execution, delivery and performance of the Amended and Restated Merger Agreement.

        For the basis of the KYTHERA Board's determinations and recommendations, please see the section entitled "—Recommendation of the KYTHERA Board and KYTHERA's Reasons for the Merger" beginning on page 54 of this proxy statement.

        On the afternoon of August 4, 2015, KYTHERA, Allergan and Merger Sub executed the Amended and Restated Merger Agreement.

Recommendation of the KYTHERA Board and KYTHERA's Reasons for the Merger

        In evaluating the Merger, the KYTHERA Board consulted with members of KYTHERA's senior management, KYTHERA's financial advisor, Goldman Sachs, and KYTHERA's outside legal counsel, Latham & Watkins, and, in the course of reaching its determination to approve the Amended and Restated Merger Agreement and the transactions contemplated thereby and to recommend that KYTHERA's stockholders vote to adopt the Amended and Restated Merger Agreement, the

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KYTHERA Board considered a range of factors, including the following principal factors supporting the KYTHERA Board's determination:

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Premia to Market Prices.  The fact that the Merger Consideration represents a premium over the market prices at which shares of common stock of KYTHERA traded prior to the announcement of the execution of the Initial Merger Agreement, including the fact that the Merger Consideration of $75.00 in cash per share of KYTHERA common stock represents a premium of approximately:



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42.3% over the $52.71 average price per share of KYTHERA common stock for the 30-day period ended June 16, 2015, the last trading day before the announcement of the execution of the Initial Merger Agreement;



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50.7% over the $49.78 average price per share of KYTHERA common stock for the 60-day period ended June 16, 2015;



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57.2% over the $47.72 average price per share of KYTHERA common stock for the 90-day period ended June 16, 2015;



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49.7% over the $50.09 closing price per share of KYTHERA common stock on June 1, 2015, one day prior to the filing on Form 8-K of KYTHERA that announced the KYTHERA Board's approval of severance and change of control benefits to certain KYTHERA executives;



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33.9% over the $56.00 highest closing price of shares of KYTHERA common stock during the 52-week period ended June 1, 2015;



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25.5% over the $59.75 closing price per share of KYTHERA common stock on June 15, 2015;



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23.5% over the $60.72 closing price per share of KYTHERA common stock on June 16, 2015, the last trading day before the announcement of the execution of the Initial Merger Agreement;



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57.8% over the $47.52 average of the closing prices of shares of KYTHERA common stock over the 30-day period ended June 1, 2015; and



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54.6% over the $48.52 volume weighted average price of shares of KYTHERA common stock between March 5, 2015 and June 1, 2015.



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Certainty of Value.  The Merger Consideration under the Amended and Restated Merger Agreement, which is comprised entirely of cash, in an amount equal to $75.00 per share of KYTHERA common stock, provides liquidity and certainty of value to KYTHERA's stockholders. The KYTHERA Board also determined that the Merger Consideration under the Amended and Restated Merger Agreement of $75.00 in cash per share of KYTHERA common stock was equivalent in value to the Initial Merger Consideration that KYTHERA stockholders would have been entitled to receive under the terms of the Initial Merger Agreement, as amended by Amendment No. 1, which would have been comprised of a fixed $75.00 in value consisting of 80% cash and 20% Allergan ordinary shares, with the cash portion of the Initial Merger Consideration equal to $60.00 per share of KYTHERA common stock and the stock portion of the Initial Merger Consideration equal to that number of validly issued, fully paid and nonassessable Allergan ordinary shares equal to the quotient determined by dividing $15.00 by the Allergan VWAP, and rounding the result to the nearest 1/10,000 of an Allergan ordinary share, with cash to be paid in lieu of fractional shares.



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Negotiations with Allergan.  The course of negotiations between KYTHERA and Allergan, which resulted in an increase in the price that Allergan was willing to pay to acquire KYTHERA of

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between $7.50 and $10.00 per share of KYTHERA common stock from the range of prices per share of KYTHERA common stock initially offered by Allergan, and the KYTHERA Board's belief, based on these negotiations, that this was the highest price per share of KYTHERA common stock that Allergan was willing to pay and that the terms of the Amended and Restated Merger Agreement were the most favorable terms to KYTHERA to which Allergan was then willing to agree.

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Stand-Alone Operational Risks.  The advantages of entering into the Amended and Restated Merger Agreement and consummating the Merger in comparison to the risks associated with remaining independent as a stand-alone company and pursuing KYTHERA's strategic plan, including (i) potential future competition, including from larger and better funded companies which might have competitive advantages from their broader commercial scope and economies of scale in pricing, (ii) the risks inherent in the pharmaceutical industry and the commercial launch of KYBELLA™, (iii) the challenges and risks associated with growing KYTHERA through either organic growth and the development of new products or strategic acquisitions, and (iv) the various additional risk factors pertaining to KYTHERA that are listed in Item 1A of Part I of its most recent annual report.



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Outreach to Other Potential Strategic Partners.  That, as directed by KYTHERA, Goldman Sachs contacted the five potential strategic counterparties which KYTHERA believed would have the highest level of interest in a business combination with, or acquisition of, KYTHERA, that would reasonably be expected to have an ability to improve upon the terms of the expression of interest from Allergan and that would reasonably be expected to have a willingness to act decisively to negotiate and consummate a transaction, each of which indicated that it was not interested in pursuing a business combination with, or acquisition of, KYTHERA.



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Strategic Alternatives.  Its understanding of, and familiarity with, the other strategic alternatives available to KYTHERA, including the outreach that took place to five other potential strategic partners, and the KYTHERA Board's belief that the Merger is superior to the other strategic alternatives currently reasonably available to KYTHERA within a reasonable timeframe.



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Likelihood of Completion.  The likelihood that the Merger will be consummated, based on, among other things, the likelihood of receiving the affirmative vote of KYTHERA's stockholders necessary to adopt the Amended and Restated Merger Agreement and consummate the Merger in a timely manner, the limited number of conditions to the closing of the Merger, the absence of a financing condition, Allergan's representation that it will have at the closing of the Merger all necessary funds to pay the aggregate Merger Consideration and consummate the Merger, the KYTHERA Board's assessment, after discussion with members of management and Goldman Sachs, that Allergan has the financial capability to consummate the Merger, the fact that, on July 24, 2015, the FTC granted early termination of the waiting period under the HSR Act with respect to the Merger and no other regulatory approvals are required as a condition to the consummation of the Merger and the remedies available under the Amended and Restated Merger Agreement to KYTHERA in the event of various breaches of the Amended and Restated Merger Agreement by Allergan or Merger Sub.



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Opinion of Goldman Sachs.  Certain financial analyses presented to the KYTHERA Board by KYTHERA's financial advisor, Goldman Sachs, and the oral opinion of Goldman Sachs delivered to the KYTHERA Board, which was subsequently confirmed by delivery of a written opinion dated as of June 17, 2015, that, as of such date and based upon and subject to the factors and assumptions set forth therein, the Initial Merger Consideration to be paid to the holders of the outstanding shares of KYTHERA common stock (other than Allergan and its affiliates) pursuant to the Initial Merger Agreement was fair from a financial point of view to those holders. Additionally, representatives from Goldman Sachs advised the KYTHERA Board,

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at a meeting of the KYTHERA Board on June 30, 2015, which advice was confirmed in writing on July 1, 2015, that, based upon and subject to the factors and assumptions stated therein, had Goldman Sachs issued its opinion on June 17, 2015 on the basis of the transactions contemplated by the Initial Merger Agreement, as amended by the proposed Amendment No. 1, the conclusion set forth in its opinion would not have changed. Furthermore, representatives from Goldman Sachs advised the KYTHERA Board, at a meeting of the KYTHERA Board on August 3, 2015, which advice was confirmed in writing on August 4, 2015, that, based upon and subject to the factors and assumptions stated therein, had Goldman Sachs issued its opinion on June 17, 2015 on the basis of the transactions contemplated by the Amended and Restated Merger Agreement, the conclusion set forth in its opinion (with references to "Consideration" therein deemed to be $75.00 in cash per outstanding share of KYTHERA common stock) would not have changed. For a discussion of Goldman Sachs' opinion rendered to the KYTHERA Board and the financial analyses presented by Goldman Sachs to the KYTHERA Board in connection with the delivery of this opinion, see the section entitled "—Opinion of Financial Advisor to KYTHERA" beginning on page 60 of this proxy statement.

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Terms of the Amended and Restated Merger Agreement.  The terms and conditions of the Amended and Restated Merger Agreement, including KYTHERA's ability under certain circumstances to respond to a bona fide unsolicited written proposal for an acquisition transaction from a third party prior to adoption of the Amended and Restated Merger Agreement by KYTHERA's stockholders, and the KYTHERA Board's right, after complying with the terms of the Amended and Restated Merger Agreement, to terminate the Amended and Restated Merger Agreement in order to enter into an agreement with respect to a superior proposal, upon payment of a termination fee of $69.75 million (approximately 3.25% of the equity value of the transaction) in cash, which the KYTHERA Board was advised is within the customary range of termination fees payable in similar transactions.



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Early Termination of the Waiting Period under the HSR Act.  On July 6, 2015, each of Allergan and KYTHERA filed a Pre-Merger Notification and Report Form pursuant to the HSR Act with the Antitrust Division of the U.S. Department of Justice and the FTC. On July 27, 2015, Allergan and KYTHERA announced that the FTC had granted early termination of the waiting period under the HSR Act with respect to the Merger. No other regulatory approvals are required as a condition to the consummation of the Merger.



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Structure and Availability of Appraisal Rights.  The fact that the Merger would be subject to the adoption of the Amended and Restated Merger Agreement by stockholders of KYTHERA holding a majority of the shares of KYTHERA common stock entitled to vote, that KYTHERA's stockholders would be free to not vote in favor of the adoption of the Amended and Restated Merger Agreement and that, if such dissenting KYTHERA stockholders so desire, and if they comply with all of the required procedures under the General Corporation Law of the State of Delaware, they will be able to exercise appraisal rights with respect to the Merger, which would allow such stockholders to seek appraisal of the fair value of their shares of KYTHERA common stock as determined by the Court.



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Speed and Likelihood of Completion.  The fact that, as a result of Allergan's entry into the Allergan-Teva Purchase Agreement, Allergan would be required to prepare and file with the SEC the Allergan-Teva unaudited pro forma financial information prior to a registration statement on Form S-4 becoming effective with respect to the stock portion of the Initial Merger Consideration to be issued to KYTHERA stockholders under the terms of the Initial Merger Agreement, as amended by Amendment No. 1, and the fact that that Allergan had informed KYTHERA that the Allergan-Teva unaudited pro forma financial information was likely to take considerable time to prepare, as well as the terms of the Amended and Restated Merger Agreement, which provides for an all cash transaction at the same $75.00 fixed value per share

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of KYTHERA common stock that would have been paid under the Initial Merger Agreement, as amended by Amendment No. 1, which cash transaction the KYTHERA Board believed could be completed more quickly than the stock and cash transaction provided for under the terms of the Initial Merger Agreement, as amended by Amendment No. 1, in light of Allergan's need to prepare the Allergan-Teva unaudited pro forma financial information. The KYTHERA Board also considered the uncertainty of timing for the completion of the Allergan-Teva unaudited pro forma financial information and the related uncertainty of timing for the completion of the transactions contemplated by the Initial Merger Agreement, as amended by Amendment No. 1, as well as the potential risks to KYTHERA's business and to the satisfaction of the remaining closing conditions to the Merger that would result from any extended delay in the preparation of the Allergan-Teva unaudited pro forma financial information and the desire of the KYTHERA Board to complete the Merger and provide the benefits of the Merger to the stockholders of KYTHERA as promptly as reasonably practicable, if the Amended and Restated Merger Agreement were to be adopted by KYTHERA's stockholders.

        The KYTHERA Board also considered a variety of risks and other potentially negative factors concerning the Merger and the Amended and Restated Merger Agreement, including the following:

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Effect of Failure to Consummate the Merger.  While KYTHERA expects that the Merger will be consummated, there can be no assurance that all of the conditions to the consummation of the Merger will be satisfied, and, as a result, it is possible that the Merger may not be consummated in a timely matter or at all, even if the Amended and Restated Merger Agreement is adopted by KYTHERA's stockholders.

The KYTHERA Board also considered potential negative effects if the Merger is not consummated, including:

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the trading price of shares of KYTHERA common stock could be adversely affected;



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KYTHERA could lose customers, suppliers, business partners and employees, including key sales and other personnel;



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KYTHERA's business may be subject to significant disruption and decline, and the launch of KYTHERA's first approved product, KYBELLA™, may be significantly disrupted or delayed;



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the market's perceptions of KYTHERA's prospects could be adversely affected;



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KYTHERA's directors, officers, and other employees would have expended considerable time and effort to negotiate, implement and consummate the Merger, and their time may have been diverted from other important business opportunities and operational matters while working to implement the Merger; and



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KYTHERA would have incurred significant transaction and opportunity costs attempting to consummate the Merger, without compensation.



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Effect of Public Announcement.  The effect of a public announcement of the Merger on KYTHERA's operations, stock price and employees, KYTHERA's ability to retain key management, KYTHERA's ability to effectively recruit replacement personnel if key sales and other personnel were to depart while the Merger was pending and the potential adverse effects on the financial results of KYTHERA as a result of any related disruption in KYTHERA's business, including any delay or disruption in the launch of KYBELLA™.



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Taxable Consideration.  The gains from the Merger Consideration received by KYTHERA's stockholders in connection with the Merger would be taxable to KYTHERA stockholders for U.S. federal income tax purposes, and any gains from any appraisal proceeding could be taxable

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for U.S. federal income tax purposes to KYTHERA's stockholders who perfect their appraisal rights.

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No Stockholder Participation in Future Growth or Earnings.  The KYTHERA Board considered that if the Merger is consummated, holders of KYTHERA common stock will receive the Merger Consideration in all cash and will no longer have the opportunity to (i) participate in any future earnings or growth of KYTHERA or the combined entity or (ii) benefit from any potential future appreciation in the value of KYTHERA common stock or the ordinary shares of the combined entity, including any value that could be achieved if the combined entity engages in future strategic or other transactions or successfully commercializes any of its products. However, the KYTHERA Board also considered the fact that holders of KYTHERA common stock will have the opportunity to invest in Allergan, if desired, by purchasing Allergan ordinary shares, which as of the date hereof is listed on the New York Stock Exchange under the symbol "AGN."



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Interim Restrictions on Business.  Restrictions imposed by the Amended and Restated Merger Agreement on the conduct of KYTHERA's business prior to the consummation of the Merger, which require KYTHERA to operate its business in the ordinary course of business, and which subject the operations of KYTHERA's business to other restrictions, which could delay or prevent KYTHERA from undertaking timely business enhancement opportunities that may arise prior to the consummation of the Merger and that may have an adverse effect on KYTHERA's ability to respond to changing market and business conditions in a timely manner or at all.



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Termination Fee.  The fact that, under certain circumstances, KYTHERA may be required to pay to Allergan a termination fee of $69.75 million (approximately 3.25% of the equity value of the transaction) in cash, including the potential that such termination fee may deter other potential acquirers from making a competing offer for KYTHERA, and the potentially deterrent impact of the termination fee on KYTHERA's ability to engage in certain transactions for nine months from the date the Amended and Restated Merger Agreement is terminated in certain circumstances.



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Speed and Likelihood of Completion.  The KYTHERA Board considered the possibility that, while the KYTHERA Board believed that amending and restating the Initial Merger Agreement, as amended by Amendment No. 1, would result in a transaction that could close more quickly than the transaction provided for under the terms of the Initial Merger Agreement, as amended by Amendment No. 1, amending and restating the Initial Merger Agreement, as amended by Amendment No. 1, could, in fact, result in a transaction that would not close as quickly as the transaction provided for under the terms of the Initial Merger Agreement, as amended by Amendment No. 1.



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Interests of the KYTHERA Board and Management.  The possibility that the executive officers and directors of KYTHERA could have interests in the transactions contemplated by the Amended and Restated Merger Agreement that would be different from, or in addition to, those of KYTHERA's stockholders. The KYTHERA Board concluded that the potential benefits that it expected KYTHERA and KYTHERA's stockholders would achieve as a result of the Merger outweighed the risks and potentially negative factors related to the Merger. The foregoing discussion of the KYTHERA Board's reasons for its recommendation to stockholders to vote to adopt the Amended and Restated Merger Agreement is not intended to be exhaustive, but addresses the material information and factors considered by the KYTHERA Board in its consideration of the Merger. In light of the wide variety of factors considered by the KYTHERA Board in connection with its evaluation of the Merger and the complexity of these matters, the KYTHERA Board did not find it practicable to, and did not, quantify or otherwise assign relative weights to, the specific reasons underlying its determination and recommendation.

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Rather, the KYTHERA Board viewed its determinations and recommendations as being based on the totality of the information and factors presented to and considered by the KYTHERA Board. In considering the factors discussed above, individual directors may have given different weights to different factors.

Opinion of Financial Advisor to KYTHERA

        Goldman Sachs delivered its opinion to the KYTHERA Board that, as of June 17, 2015 and based upon and subject to the factors and assumptions set forth therein, the Initial Merger Consideration to be paid to the holders of the outstanding shares of KYTHERA common stock (other than Allergan and its affiliates) pursuant to the Initial Merger Agreement was fair from a financial point of view to those holders. On July 1, 2015, Goldman Sachs delivered a letter to the KYTHERA Board confirming that, based upon and subject to the factors and assumptions stated therein, had Goldman Sachs issued its opinion on June 17, 2015 on the basis of the transactions contemplated by the Initial Merger Agreement, as amended by Amendment No. 1, the conclusion set forth in its opinion would not have changed. The confirmation letter dated July 1, 2015 did not address any circumstances, developments or events occurring after June 17, 2015, other than the execution of Amendment No. 1, and its opinion is provided only as of such date. In connection with the delivery of the confirmation letter dated July 1, 2015, the KYTHERA Board advised Goldman Sachs, and with the KYTHERA Board's permission, Goldman Sachs assumed, that changes to the Initial Merger Agreement pursuant to Amendment No. 1 and the transactions contemplated thereby did not affect the Final Unaudited Prospective Financial Information, as defined under the section entitled "KYTHERA Unaudited Prospective Financial Information." On August 4, 2015, Goldman Sachs delivered a letter to the KYTHERA Board confirming that, based upon and subject to the factors and assumptions stated therein, had Goldman Sachs issued its opinion on June 17, 2015 on the basis of the transactions contemplated by the Amended and Restated Merger Agreement, the conclusion set forth in its opinion (with references to "Consideration" therein deemed to be $75.00 in cash per outstanding share of KYTHERA common stock) would not have changed. The confirmation letter dated August 4, 2015 did not address any circumstances, developments or events occurring after June 17, 2015, other than the execution of the Amended and Restated Merger Agreement, and its opinion is provided only as of such date. In connection with the delivery of the confirmation letter dated August 4, 2015, the KYTHERA Board advised Goldman Sachs, and with the KYTHERA Board's permission, Goldman Sachs assumed, that the changes to the Initial Merger Agreement pursuant to the Amended and Restated Merger Agreement and the transactions contemplated thereby did not affect the Final Unaudited Prospective Financial Information.

        The full text of the written opinion of Goldman Sachs, dated June 17, 2015, which sets forth assumptions made, procedures followed, matters considered, qualifications and limitations on the review undertaken in connection with the opinion, is attached as Annex C. The full text of the confirmation letter of Goldman Sachs, dated July 1, 2015, which sets forth assumptions made, procedures followed, matters considered, qualifications and limitations on the review undertaken in connection with the letter, is attached as Annex D. The full text of the confirmation letter of Goldman Sachs, dated August 4, 2015, which sets forth assumptions made, procedures followed, matters considered, qualifications and limitations on the review undertaken in connection with the letter, is attached as Annex E. The summary of the Goldman Sachs opinion provided is qualified in its entirety by reference to the full text of the written opinion. Goldman Sachs provided its opinion and each confirmation letter for the information and assistance of the KYTHERA Board in connection with its consideration of the Merger. Neither the Goldman Sachs opinion nor either Goldman Sachs confirmation letter is a recommendation as to how any holder of shares of KYTHERA common stock should vote with respect to the Merger, or any other matter.

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        In connection with rendering the opinion described above and performing its related financial analyses, Goldman Sachs reviewed, among other things:

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the Initial Merger Agreement;



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annual reports to stockholders and Annual Reports on Form 10-K of KYTHERA for the three fiscal years ended December 31, 2014;



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KYTHERA's Registration Statement on Form S-1, including the preliminary prospectus contained therein dated October 9, 2012 relating to the initial public offering of shares of KYTHERA common stock;



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annual reports to stockholders and Annual Reports on Form 10-K of Allergan and Allergan, Inc. for the three fiscal years ended December 31, 2014;



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certain interim reports to stockholders and Quarterly Reports on Form 10-Q of KYTHERA and Allergan;



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certain other communications from KYTHERA and Allergan to their respective stockholders;



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certain publicly available research analyst reports for KYTHERA and Allergan; and



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the Final Unaudited Prospective Financial Information. Goldman Sachs also held discussions with members of the senior management of KYTHERA regarding their assessment of the past and current business operations, financial condition and future prospects of KYTHERA and Allergan; reviewed the reported price and trading activity for shares of KYTHERA common stock and Allergan ordinary shares; compared certain financial and stock market information for KYTHERA and Allergan with similar information for certain other companies the securities of which are publicly traded; reviewed the financial terms of certain recent business combinations in the biotechnology industry and in other industries; and performed such other studies and analyses, and considered such other factors, as it deemed appropriate.

        For purposes of rendering the opinion described above, Goldman Sachs, with the consent of the KYTHERA Board, relied upon and assumed the accuracy and completeness of all of the financial, legal, regulatory, tax, accounting and other information provided to, discussed with or reviewed by it, without assuming any responsibility for independent verification thereof. In that regard, Goldman Sachs assumed with the consent of the KYTHERA Board that the Final Unaudited Prospective Financial Information was reasonably prepared on a basis reflecting the best then currently available estimates and judgments of KYTHERA's management. Goldman Sachs did not make an independent evaluation or appraisal of the assets and liabilities (including any contingent, derivative or other off-balance-sheet assets and liabilities) of KYTHERA or Allergan or any of their respective subsidiaries, nor was any evaluation or appraisal of the assets or liabilities of KYTHERA or Allergan or any of their respective subsidiaries furnished to Goldman Sachs. Goldman Sachs assumed that all governmental, regulatory or other consents and approvals necessary for the consummation of the Merger will be obtained without any adverse effect on KYTHERA or Allergan or any of their respective subsidiaries or on the expected benefits of the Merger in any way meaningful to its analysis. Goldman Sachs has also assumed that the Merger will be consummated on the terms set forth in the Initial Merger Agreement, without the waiver or modification of any term or condition the effect of which would be in any way meaningful to its analysis.

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        Goldman Sachs' opinion does not address the underlying business decision of KYTHERA to engage in the Merger or the relative merits of the Merger as compared to any strategic alternatives that may be available to KYTHERA; nor does it address any legal, regulatory, tax or accounting matters. Goldman Sachs' opinion addressed only the fairness from a financial point of view to the holders of the outstanding shares of KYTHERA common stock (other than Allergan and its affiliates) as of the date of the opinion, of the Initial Merger Consideration to be paid to such holders pursuant to the Initial Merger Agreement. Goldman Sachs' opinion does not express any view on, and does not address, any other term or aspect of the Initial Merger Agreement or the Merger or any term or aspect of any other agreement or instrument contemplated by the Initial Merger Agreement or entered into or amended in connection with the Merger, including, the fairness of the Merger to, or any consideration received in connection therewith by, the holders of any other class of securities, creditors, or other constituencies of KYTHERA; nor as to the fairness of the amount or nature of any compensation to be paid or payable to any of the officers, directors or employees of KYTHERA, or class of such persons, in connection with the Merger, whether relative to the Initial Merger Consideration to be paid to the holders of the outstanding shares of KYTHERA common stock (other than Allergan and its affiliates) pursuant to the Initial Merger Agreement or otherwise. Goldman Sachs did not express any opinion as to the prices at which Allergan ordinary shares will trade at any time or as to the impact of the Merger on the solvency or viability of KYTHERA or Allergan or the ability of KYTHERA or Allergan to pay their respective obligations when they come due. Goldman Sachs' opinion was necessarily based on economic, monetary, market and other conditions as in effect on, and the information made available to it as of, the date of its opinion and Goldman Sachs assumed no responsibility for updating, revising or reaffirming its opinion based on circumstances, developments or events occurring after the date of its opinion. Goldman Sachs' opinion was provided for the information and assistance of the KYTHERA Board in connection with its consideration of the Merger and such opinion does not constitute a recommendation as to how any holder of shares of KYTHERA common stock should vote with respect to the Merger or any other matter. Goldman Sachs' opinion was approved by a fairness committee of Goldman Sachs.

        The following is a summary of the material financial analyses delivered by Goldman Sachs to the KYTHERA Board in connection with rendering the opinion described above. The following summary, however, does not purport to be a complete description of the financial analyses performed by Goldman Sachs, nor does the order of analyses described represent relative importance or weight given to those analyses by Goldman Sachs. Some of the summaries of the financial analyses include information presented in tabular format. The tables must be read together with the full text of each summary and are alone not a complete description of Goldman Sachs' financial analyses. Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before June 15, 2015 and is not necessarily indicative of current market conditions.

Discounted Cash Flow Analysis

        Goldman Sachs performed a discounted cash flow analysis of KYTHERA to derive a range of illustrative present values per share of KYTHERA common stock. Using discount rates ranging from 10.5% to 12.5%, reflecting an estimate of KYTHERA's weighted average cost of capital, Goldman Sachs discounted to present value as of March 31, 2015, (i) estimates of the unlevered free cash flow to be generated by KYTHERA during the period from April 1, 2015 through the end of KYTHERA's fiscal year ended December 31, 2030 (referred to in this section of the proxy statement as "FY 2030"), reflected in the Final Unaudited Prospective Financial Information, and (ii) a range of illustrative terminal values for KYTHERA as of December 31, 2030, calculated by applying perpetuity growth rates ranging from (25.0)% to (5.0)% to a terminal year estimate of the unlevered free cash flow to be generated by KYTHERA, which unlevered free cash flows for April 1, 2015 through FY 2030 are reflected in the Final Unaudited Prospective Financial Information. In addition, using a discount rate

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of 10.5%, reflecting an estimate of KYTHERA's cost of equity, Goldman Sachs discounted to present value as of March 31, 2015, the estimated benefits of KYTHERA's net operating losses (referred to in this section of the proxy statement as "NOLs") and research and development (referred to in this section of the proxy statement as "R&D") tax credits from April 1, 2015 through FY 2030, as reflected in the Final Unaudited Prospective Financial Information. Goldman Sachs derived ranges of illustrative enterprise values for KYTHERA by adding (i) the ranges of present values it derived based on the estimated unlevered free cash flows of KYTHERA for the period from April 1, 2015 through FY 2030, (ii) the ranges of present value it derived based on the illustrative terminal values for KYTHERA as of December 31, 2030 and (iii) the present value derived for the estimated benefits of KYTHERA's NOLs and R&D tax credits for the period from April 1, 2015 through FY 2030. Goldman Sachs added to the range of illustrative enterprise values it derived for KYTHERA the amount of KYTHERA's net cash (derived by adding the amount of KYTHERA's cash and cash equivalents and marketable securities as of March 31, 2015 and subtracting the principal amount of KYTHERA's notes payable as of March 31, 2015, pro forma for the April 1, 2015 pay down of the credit facility under the Loan and Security Agreement No. 1991, dated as of March 21, 2011, between Lighthouse Capital Partners VI, L.P. and KYTHERA, and divided the results by the number of fully diluted shares of KYTHERA common stock, calculated on a treasury method basis, using information provided by KYTHERA management, as of June 15, 2015, to derive illustrative present values for shares of KYTHERA common stock ranging from $53.76 to $78.03.

Implied Premia Analysis

        Goldman Sachs analyzed the Initial Merger Consideration of $75.00 per share of KYTHERA common stock in relation to historical trading prices of shares of KYTHERA common stock. This analysis indicated that the Initial Merger Consideration of $75.00 per share of KYTHERA common stock represented:

•

a premium of 25.5% to the closing price of shares of KYTHERA common stock of $59.75 on June 15, 2015;



•

a premium of 49.7% to the closing price of shares of KYTHERA common stock of $50.09 on June 1, 2015, one day prior to the filing on Form 8-K of KYTHERA that announced the KYTHERA Board's approval of severance and change of control benefits to certain KYTHERA executives, which date is referred to in this proxy statement as the "last undisturbed trading day for shares of KYTHERA common stock";



•

a premium of 57.8% to the average of the closing prices of shares of KYTHERA common stock of $47.52 over the 30-day period ended June 1, 2015;



•

a premium of 33.9% to the highest closing price of shares of KYTHERA common stock of $56.00 during the 52-week period ended June 1, 2015; and



•

a premium of 54.6% to the volume weighted average price of shares of KYTHERA common stock of $48.52 between March 5, 2015 and June 1, 2015.

Selected Precedent Transactions Premia Analysis

        Goldman Sachs analyzed certain publicly available information relating to the late-stage biotechnology transactions listed below announced between May 16, 2010 and June 15, 2015 reflecting transaction values between $1 billion and $5 billion. With respect to each of these transactions, Goldman Sachs calculated the one day premium represented by the announced per share transaction price to the closing price of the target company's common stock on the last trading day before the

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public announcement of the transaction (or the last undisturbed closing price for the target company's common stock). The results of this analysis are listed below:

        Although none of the selected precedent transactions is directly comparable to the proposed Merger, the selected precedent transactions involved late-stage biotechnology transactions with transaction values in a range similar to the enterprise value of KYTHERA based on the Initial Merger Consideration of $75.00 per share of KYTHERA common stock. As such, for the purposes of this analysis, the selected precedent transactions may be considered similar to the proposed Merger.

        Based on its review of the implied premia for the selected precedent transactions and its professional judgment and experience, Goldman Sachs applied illustrative premia ranging from 40.0% to 60.0% to the closing price of shares of KYTHERA common stock as of June 1, 2015 (the last undisturbed trading day for shares of KYTHERA common stock) to derive illustrative values for shares of KYTHERA common stock ranging from $70.13 to $80.14.

General

        The preparation of a fairness opinion is a complex process and is not necessarily susceptible to partial analysis or summary description. Selecting portions of the analyses or of the summary set forth above, without considering the analyses as a whole, could create an incomplete view of the processes underlying Goldman Sachs' opinion. In arriving at its fairness determination, Goldman Sachs considered the results of all of its analyses and did not attribute any particular weight to any factor or analysis considered by it. Rather, Goldman Sachs made its determination as to fairness on the basis of its experience and professional judgment after considering the results of all of its analyses. No company or transaction used in the above analyses as a comparison is directly comparable to KYTHERA or Allergan or the contemplated Merger.

        Goldman Sachs prepared these analyses for purposes of Goldman Sachs' providing its opinion to the KYTHERA Board as to the fairness from a financial point of view of the Initial Merger Consideration to be paid to the holders of the outstanding shares of KYTHERA common stock (other than Allergan and its affiliates) pursuant to the Initial Merger Agreement. These analyses do not purport to be appraisals nor do they necessarily reflect the prices at which businesses or securities actually may be sold. Analyses based upon forecasts of future results are not necessarily indicative of actual future results, which may be significantly more or less favorable than suggested by these analyses. Because these analyses are inherently subject to uncertainty, being based upon numerous factors or events beyond the control of the parties or their respective advisors, none of KYTHERA, Allergan, Goldman Sachs or any other person assumes responsibility if future results are materially different from those forecast.

        The Initial Merger Consideration was determined through arm's-length negotiations between KYTHERA and Allergan and was approved by the KYTHERA Board. Goldman Sachs provided advice to KYTHERA during these negotiations. Goldman Sachs did not, however, recommend any specific

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amount or form of consideration to KYTHERA or its Board or that any specific amount or form of consideration constituted the only appropriate consideration for the Merger.

        As described above, Goldman Sachs' opinion to the KYTHERA Board was one of many factors taken into consideration by the KYTHERA Board in making its determination to approve the Initial Merger Agreement. The foregoing summary does not purport to be a complete description of the analyses performed by Goldman Sachs in connection with the fairness opinion and is qualified in its entirety by reference to the written opinion of Goldman Sachs attached as Annex C.

        Goldman Sachs and its affiliates are engaged in advisory, underwriting and financing, principal investing, sales and trading, research, investment management and other financial and non-financial activities and services for various persons and entities. Goldman Sachs and its affiliates and employees, and funds or other entities they manage or in which they invest or have other economic interests or with which they co-invest, may at any time purchase, sell, hold or vote long or short positions and investments in securities, derivatives, loans, commodities, currencies, credit default swaps and other financial instruments of KYTHERA, Allergan, any of their respective affiliates and third parties or any currency or commodity that may be involved in the transaction contemplated by the Initial Merger Agreement. Goldman Sachs acted as financial advisor to KYTHERA in connection with, and participated in certain of the negotiations leading to, the Merger. Goldman Sachs also has provided certain financial advisory and/or underwriting services to KYTHERA and/or its affiliates from time to time for which the Investment Banking Division of Goldman Sachs has received, and may receive, compensation, including having acted as lead-left bookrunner to KYTHERA's March 2015 follow-on equity financing. During the two-year period ended June 17, 2015, the Investment Banking Division of Goldman Sachs had received aggregate compensation for financial advisory and/or underwriting services provided to KYTHERA and/or its affiliates of approximately $3.3 million. During the two-year period ended June 17, 2015, the Investment Banking Division of Goldman Sachs had not provided any financial advisory and/or underwriting services for Allergan (formerly Actavis plc) for which it received compensation. Goldman Sachs may also in the future provide financial advisory and/or underwriting services to KYTHERA, Allergan and their respective affiliates for which the Investment Banking Division of Goldman Sachs may receive compensation.

        The KYTHERA Board selected Goldman Sachs as its financial advisor because it is an internationally recognized investment banking firm that has substantial experience in transactions similar to the Merger. Pursuant to a letter agreement dated May 27, 2015, KYTHERA engaged Goldman Sachs to act as its financial advisor in connection with the Merger. Pursuant to the terms of the engagement letter, KYTHERA has agreed to pay Goldman Sachs a transaction fee of $24.2 million in connection with the Merger, all of which is payable contingent upon consummation of the Merger. In addition, KYTHERA has agreed to reimburse Goldman Sachs for certain of its expenses arising out its engagement, including attorneys' fees and disbursements, and to indemnify Goldman Sachs and related persons against various liabilities that may arise arising out its engagement, including certain liabilities under the federal securities laws.

KYTHERA Unaudited Prospective Financial Information

        In KYTHERA's press releases announcing its annual operating results, KYTHERA has from time to time provided public guidance as to the sufficiency of its cash and cash equivalents to fund its operating plan over a 12-month period, its projected year-end cash balance, and general guidance as to expected increases in costs as KYTHERA has prepared for the commercial launch of its primary product, KYBELLA™. KYTHERA's press release announcing its annual operating results for 2014 stated that KYTHERA believed its existing cash and cash equivalents would allow it to fund its operations through at least the next 12 months, and was furnished to the SEC on Form 8-K on March 2, 2015. KYTHERA does not otherwise publicly disclose projections as to future revenues,

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earnings or other results due to, among other reasons, the uncertainty and subjectivity of the underlying assumptions and estimates.

        In the normal course of business planning, each year KYTHERA's management prepares, for internal use, certain unaudited prospective financial information with respect to KYTHERA's business plans for the immediately succeeding five-year period. This unaudited prospective financial information is part of its annual internal financial planning processes and is discussed, reviewed and approved by the KYTHERA Board annually. Consistent with the normal course of business, KYTHERA's management prepared during the second half of 2014, and completed in December 2014, for internal use, certain unaudited prospective financial information with respect to KYTHERA's business plans for fiscal years 2015 through 2019 (referred to in this proxy statement as the "Long-Range Plan"). The Long-Range Plan was presented by KYTHERA management to the KYTHERA Board for their review and approval at a meeting of the KYTHERA Board on December 4, 2014. Consistent with the normal course of business, KYTHERA's management prepared during the second half of 2014, and completed in December 2014, for internal use, certain unaudited projected revenues with respect to potential co-promotion and partnership arrangements outside of the U.S. with respect to KYBELLA™ for fiscal years 2015 through 2024 (referred to in this proxy statement as the "Ex-U.S. Revenue Models"), which formed the basis for a corporate strategy review with the KYTHERA Board in September 2014. In March 2015, members of KYTHERA's senior management requested that Goldman Sachs begin to prepare for a discussion with the KYTHERA Board at a regularly scheduled meeting of the KYTHERA Board on June 2, 2015 and provided Goldman Sachs with the Long-Range Plan and the Ex-U.S. Revenue Models in connection with Goldman Sachs' preparation of a preliminary financial analysis of KYTHERA for such meeting. The Long-Range Plan and Ex-U.S. Revenue Models were developed at a different time, using different assumptions and for a different purpose than, and are independent from, the April 27, 2015 Preliminary Unaudited Prospective Financial Information, the May 26, 2015 Preliminary Unaudited Prospective Financial Information and the Final Unaudited Prospective Financial Information described below.

        After the receipt by KYTHERA from Allergan, on April 23, 2015, of a written preliminary non-binding expression of interest in an acquisition of KYTHERA by Allergan, KYTHERA's management prepared an initial set of long-range probability adjusted prospective financial information for KYTHERA with respect to fiscal years 2015 through 2030 (such long-range probability adjusted prospective financial information for KYTHERA, which was prepared by KYTHERA's management and presented at the April 27, 2015 meeting of the KYTHERA Board, referred to in this proxy statement as the "April 27, 2015 Preliminary Unaudited Prospective Financial Information"). The April 27, 2015 Preliminary Unaudited Prospective Financial Information was presented to the KYTHERA Board at its meeting held on April 27, 2015 and used by Goldman Sachs in connection with Goldman Sachs' preparation of a preliminary financial analysis with respect to KYTHERA that was also presented at the KYTHERA Board meeting held on April 27, 2015. Following the April 27, 2015 meeting of KYTHERA's Board, KYTHERA's management updated the April 27, 2015 Preliminary Unaudited Prospective Financial Information on two occasions, in each case to further refine certain of the assumptions and estimates included therein to better reflect the information available to KYTHERA's management at the time of each such update. The first update of the long-range probability adjusted prospective financial information for KYTHERA was prepared by KYTHERA's management, presented to the KYTHERA Board at its meeting held on May 26, 2015 and used by Goldman Sachs in connection with Goldman Sachs' preparation of a preliminary financial analysis with respect to KYTHERA that was also presented at the KYTHERA Board meeting held on May 26, 2015 (such long-range probability adjusted prospective financial information for KYTHERA which was prepared by KYTHERA's management and presented at the May 26, 2015 meeting of the KYTHERA Board is referred to in this proxy statement as the "May 26, 2015 Preliminary Unaudited Prospective Financial Information"). The second and final update of the long-range probability adjusted prospective financial information for KYTHERA was prepared by KYTHERA's management, presented to the

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KYTHERA Board at its meetings held on June 2, 2015 and June 16, 2015 and used by Goldman Sachs in connection with Goldman Sachs' preparation of its financial analysis of the Initial Merger Consideration that was also presented at the KYTHERA Board meetings held on June 2, 2015 and June 16, 2015 (such long-range probability adjusted prospective financial information for KYTHERA which was prepared by KYTHERA's management and presented at the KYTHERA Board meetings held on June 2, 2015 and June 16, 2015 is referred to in this proxy statement as the "Final Unaudited Prospective Financial Information").

        KYTHERA did not provide any financial forecasts, including the Long-Range Plan, the Ex-U.S. Revenue Models, the April 27, 2015 Preliminary Unaudited Prospective Financial Information, the May 26, 2015 Preliminary Unaudited Prospective Financial Information or the Final Unaudited Prospective Financial Information (each referred to in this proxy statement as a "Forecast" and collectively, referred to in this proxy statement as, the "Forecasts"), to Allergan or any other third parties in connection with a potential acquisition of KYTHERA. KYTHERA is including the Final Unaudited Prospective Financial Information in this proxy statement solely because it was the most recent financial information made available to Goldman Sachs in connection with its financial analysis and to the KYTHERA Board in connection with its evaluation of the Merger. The Long-Range Plan, the Ex-U.S. Revenue Models, the April 27, 2015 Preliminary Unaudited Prospective Financial Information and the May 26, 2015 Preliminary Unaudited Prospective Financial Information made available to the KYTHERA Board were not relied upon by the KYTHERA Board in reaching its determination on June 16, 2015 to approve the Initial Merger Agreement and the transactions contemplated thereby and to recommend that KYTHERA's stockholders vote to adopt the Initial Merger Agreement, and the Final Unaudited Prospective Financial Information was the only Forecast approved by KYTHERA for use by Goldman Sachs in connection with rendering its oral opinion delivered to the KYTHERA Board, which was subsequently confirmed by delivery of a written opinion dated as of June 17, 2015, and performing its financial analysis in connection therewith.

        KYTHERA's internally prepared Final Unaudited Prospective Financial Information was based solely upon information available to KYTHERA's management as of the date in the second quarter of fiscal 2015 and estimates and assumptions made by KYTHERA's management as of the date in the second quarter of fiscal 2015 when the Final Unaudited Prospective Financial Information was prepared. Similarly, each other Forecast internally prepared by KYTHERA was based solely upon information available to KYTHERA's management at the time such Forecast was prepared and estimates and assumptions made by KYTHERA's management at such time, and each such Forecast speaks only as of the time that such Forecast was prepared. As a result, the Final Unaudited Prospective Financial Information and each other Forecast does not necessarily reflect KYTHERA's current estimates and does not take into account any circumstances or events occurring after the date it was prepared, and some or all of the assumptions made regarding, among other things, the timing of certain occurrences or impacts, may have changed since such date. In addition, the Final Unaudited Prospective Financial Information and each other Forecast does not give effect to the Merger or any changes to KYTHERA's operations or strategy that may be implemented as a result of the announcement of the Merger or following the consummation of the Merger or to any costs incurred in connection with the Merger. Further, the Final Unaudited Prospective Financial Information and each other Forecast does not take into account the effect of any failure of the consummation of the Merger to occur and should not be viewed as accurate or continuing in that context.

        The Final Unaudited Prospective Financial Information and each other Forecast was necessarily based on a variety of assumptions and estimates. Certain of these assumptions and estimates either have not or may not be realized. All such estimates and assumptions are inherently subject to significant business, economic and competitive uncertainties and contingencies, all of which are difficult to predict and many of which are beyond KYTHERA's control. The assumptions and estimates used to create the Final Unaudited Prospective Financial Information and each other Forecast involve

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judgments made with respect to, among other things, when KYBELLA™ and Setipiprant (KYTH-105), KYTHERA's planned product for the treatment of hair loss, would be available in the market, the internal cost of KYBELLA™ and KYTH-105, product pricing of KYBELLA™ and KYTH-105, the patient population and adoption rate for KYBELLA™ and KYTH-105 during the forecast period, the ability of KYTHERA to maintain market share, patient population and adoption rate, selling and marketing expenses, research and development spending, general and administrative expenses, the availability of net operating losses, future global effective income tax rates and other factors described under "Risk Factors" in KYTHERA's annual report on Form 10-K for the fiscal year ended December 31, 2014 and KYTHERA's other filings with the SEC, all of which are difficult to predict and some of which are outside of KYTHERA's control. In addition, the Final Unaudited Prospective Financial Information and each other Forecast covers multiple years, and such information by its nature becomes more uncertain with each successive year. Accordingly, there can be no assurance that any of the assumptions and estimates used to prepare the Final Unaudited Prospective Financial Information or any other Forecast will prove to be accurate, and actual results may differ materially from those shown in the Final Unaudited Prospective Financial Information.

        The Final Unaudited Prospective Financial Information is not being included in this proxy statement in order to influence any KYTHERA stockholder's decision as to whether or not to adopt the Amended and Restated Merger Agreement or whether or not to seek appraisal rights with respect to shares of KYTHERA common stock held by such stockholder. The inclusion of the Final Unaudited Prospective Financial Information in this proxy statement should not be regarded as an indication that KYTHERA, Allergan or any of KYTHERA's or Allergan's respective advisors or representatives considered or consider the Final Unaudited Prospective Financial Information to be an accurate prediction of future results or events, and the Final Unaudited Prospective Financial Information should not be relied upon as such. There can be no assurance that KYTHERA's prospective results will be realized or that actual results will not be significantly higher or lower than estimated. None of KYTHERA, Allergan or any of KYTHERA's or Allergan's respective advisors or representatives has made or makes any representation regarding the information contained in the Final Unaudited Prospective Financial Information or any other Forecast or assumes any responsibility for the validity, reasonableness, accuracy or completeness of the Final Unaudited Prospective Financial Information included in this proxy statement. In particular, neither KYTHERA nor Allergan has made any representation to any other person concerning the Final Unaudited Prospective Financial Information or any other Forecast.

        EXCEPT AS MAY BE REQUIRED BY APPLICABLE SECURITIES LAWS, NONE OF KYTHERA, ALLERGAN OR ANY OF KYTHERA'S OR ALLERGAN'S RESPECTIVE ADVISORS OR REPRESENTATIVES INTENDS TO UPDATE OR OTHERWISE REVISE OR RECONCILE THE FINAL UNAUDITED PROSPECTIVE FINANCIAL INFORMATION OR ANY OTHER FORECASTS TO REFLECT CIRCUMSTANCES EXISTING AFTER THE DATE SUCH FINAL UNAUDITED PROSPECTIVE FINANCIAL INFORMATION OR OTHER FORECASTS, AS APPLICABLE, WAS GENERATED OR TO REFLECT THE OCCURRENCE OF FUTURE EVENTS, EVEN IN THE EVENT THAT ANY OR ALL OF THE ASSUMPTIONS UNDERLYING THE FINAL UNAUDITED PROSPECTIVE FINANCIAL INFORMATION OR OTHER FORECAST ARE SHOWN TO BE IN ERROR. KYTHERA'S STOCKHOLDERS ARE CAUTIONED NOT TO PLACE UNDUE RELIANCE ON THE FINAL UNAUDITED PROSPECTIVE FINANCIAL INFORMATION INCLUDED IN THIS PROXY STATEMENT, AND SUCH UNAUDITED PROSPECTIVE FINANCIAL INFORMATION SHOULD NOT BE REGARDED AS AN INDICATION THAT KYTHERA, THE KYTHERA BOARD, GOLDMAN SACHS, ALLERGAN OR ANY OTHER PERSON CONSIDERED, OR NOW CONSIDERS, THEM TO BE RELIABLE PREDICTIONS OF FUTURE RESULTS, AND THEY SHOULD NOT BE RELIED UPON AS SUCH.

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        The Final Unaudited Prospective Financial Information and each other Forecast was not prepared with a view toward public disclosure, nor was it prepared with a view toward compliance with published guidelines of the SEC or the guidelines established by the American Institute of Certified Public Accountants for preparation and presentation of prospective financial information. The Final Unaudited Prospective Financial Information and each other Forecast does not purport to present operations in accordance with U.S. GAAP, and KYTHERA's, Allergan's or any other independent registered public accounting firm has not audited, reviewed, examined, compiled or otherwise applied or performed any procedures with respect to the Final Unaudited Prospective Financial Information or any other Forecast or any information contained therein, nor have they expressed any opinion or given any form of assurance with respect to such information or its reasonableness, achievability or accuracy, and accordingly such registered public accounting firm assumes no responsibility therefor. The reports of the independent registered public accounting firms of KYTHERA and Allergan contained in the Annual Reports of KYTHERA or Allergan on Form 10-K for the year ended December 31, 2014, which are incorporated by reference into this proxy statement, relate to the historical financial information of KYTHERA or Allergan. They do not extend to the Final Unaudited Prospective Financial Information or any other Forecast and should not be read to do so.

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        The Summary P&L and the Unlevered Free Cash Flow & Net Operating Loss Usage tables below together present the Final Unaudited Prospective Financial Information as presented to the KYTHERA Board on June 2, 2015 and on June 16, 2015, the date on which the KYTHERA Board approved the Initial Merger Agreement and the acquisition by Allergan: