OMTH Omthera Pharmaceuticals, Inc. (MM)

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS
July 16, 2013

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         WHETHER OR NOT YOU PLAN TO ATTEND THE SPECIAL MEETING, PLEASE COMPLETE, DATE, SIGN AND RETURN, AS PROMPTLY AS POSSIBLE, THE ENCLOSED PROXY CARD IN THE ACCOMPANYING PREPAID REPLY ENVELOPE, OR SUBMIT YOUR PROXY BY TELEPHONE OR THE INTERNET. IF YOU ATTEND THE SPECIAL MEETING AND VOTE IN PERSON, YOUR VOTE BY BALLOT WILL REVOKE ANY PROXY PREVIOUSLY SUBMITTED.

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        This proxy statement and a proxy card are first being mailed on or about June 14, 2013 to stockholders who owned shares of Company common stock as of the close of business on June 13, 2013.

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QUESTIONS AND ANSWERS ABOUT THE SPECIAL MEETING AND THE MERGER

         The following questions and answers are intended to address briefly some commonly asked questions regarding the merger, the merger agreement, the CVR agreement and the special meeting. These questions and answers may not address all questions that may be important to you as a Company stockholder. Please refer to the "Summary" and the more detailed information contained elsewhere in this proxy statement, the annexes to this proxy statement and the documents referred to in this proxy statement, which you should read carefully and in their entirety. You may obtain the information incorporated by reference in this proxy statement without charge by following the instructions under "Where You Can Find More Information" beginning on page 92.

Q.

What is the proposed merger transaction and what effects will it have on the Company?

A.

The proposed transaction is the acquisition of the Company by Parent pursuant to the merger agreement. If the proposal to adopt the merger agreement is approved by our stockholders and the other closing conditions under the merger agreement have been satisfied or waived, Merger Subsidiary will merge with and into the Company, with the Company being the surviving corporation. We refer to this transaction as the merger. As a result of the merger, the Company will become a subsidiary of Parent and will no longer be a publicly held corporation, and you will no longer have any interest in our future earnings or growth. In addition, following the merger, the Company common stock will be delisted from the NASDAQ Global Market and deregistered under the Exchange Act, and we will no longer file reports with the SEC on account of Company common stock.

Q.

What will I receive if the merger is completed?

A.

Upon completion of the merger, for each share of Company common stock that you own (unless you have properly exercised and not withdrawn your appraisal rights under the DGCL) you will be entitled to receive (i) $12.70 in cash, without interest, less any applicable withholding taxes, plus (ii) one CVR, which represents the right to receive contingent payments of up to approximately $4.70 in cash in the aggregate, without interest, less any applicable withholding taxes, if certain specified milestones are achieved within agreed upon time periods. For example, if you own 100 shares of Company common stock, you will receive $1,270.00 in cash consideration plus a CVR representing the right to receive contingent payments of up to an additional approximately $470.00 in cash in the aggregate if specified milestones are achieved within agreed upon time periods, subject to and in accordance with the terms and conditions of the CVR agreement.

Q.

What are the CVRs?

A.

The CVRs represent the non-transferable contractual right to receive the following cash payments from Parent, conditioned upon the achievement of certain milestones as follows:

•

approximately $1.18 per CVR if (i) the Milestone #1 Regulatory Approval (as defined herein on page 76) is attained at any time during period commencing on the date of the CVR agreement and ending on July 31, 2014 and (ii) the Milestone #1 Determination (as defined herein on page 76) is received on or before September 30, 2014;

•

approximately $3.52 per CVR if Milestone #2 (as defined herein on page 76) is attained at any time during the period commencing on the date of the CVR agreement and ending on March 31, 2016; and

•

up to approximately $4.70, less any milestone payments previously paid pursuant to the foregoing, if Milestone #3 (as defined herein on page 77) is attained at any time during the period commencing on the date of the CVR agreement and ending on December 31, 2020.

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Parent has agreed to use commercially reasonable efforts (as described herein on page 78) to achieve the milestones, subject to certain limitations agreed to in the CVR agreement.

The CVRs generally may not be sold, assigned, transferred, pledged, encumbered or transferred or disposed of in any other manner, in whole or in part, other than in the limited circumstances specified in the CVR agreement. In addition, the CVRs (i) will not be evidenced by a certificate or other instrument, (ii) will not have any voting or dividend rights and (iii) will not represent any equity or ownership interest in Parent, any constituent company to the merger or any of their respective affiliates. No interest will accrue on any amounts payable in respect of the CVRs.

For a more detailed description of the CVRs and the CVR agreement, see "The CVRs" beginning on page 76.

Q.

If the merger is completed, what will happen to the Company's stock options, restricted shares and warrants?

A.

Stock Options .    The merger agreement requires the Company to take all action necessary to cause each stock option to be vested and exercisable at least ten business days prior to the closing date. At least ten business days prior to the closing date, the Company must provide written notice to each holder of stock options that such holder will have the right, during the period beginning on the date of such notice and ending two business days prior to the closing date, to exercise such stock options by providing the Company with notice of exercise and full payment of the applicable exercise price using any method permitted by such stock options (other than by delivery of a promissory note). Each stock option that remains unexercised immediately prior to the effective time of the merger will be cancelled at such time without consideration therefor.

Restricted Stock .    Each share of Company common stock subject to vesting, repurchase or other lapse restrictions that is outstanding immediately prior to the effective time of the merger, which we refer to as restricted shares, will be vested and all restrictions thereon will lapse and each such restricted share will be converted into the right to receive the merger consideration.

Warrants .    The merger agreement requires the Company to take all action necessary to cause, at the effective time of the merger, each outstanding unexercised warrant to purchase shares of Company common stock, whether or not exercisable, to be cancelled and converted into the right to receive (subject to any applicable withholding tax) (i) an amount in cash equal to the product of (A) the excess, if any, of the cash consideration over the applicable exercise price per share of Company common stock of such warrant multiplied by (B) the total number of shares of Company common stock subject to such warrant, and (ii) one CVR multiplied by the total number of shares of Company common stock subject to such warrant.

Q.

How does the per share cash consideration compare to the market price of Company common stock prior to announcement of the merger?

A.

The per share cash consideration represents a premium of approximately (i) 88% over the closing price per share of Company common stock on May 24, 2013, the last trading day prior to public announcement of the execution of the merger agreement, (ii) 59% over the per share offering price of Company common stock in its initial public offering, and (iii) 78% over the average price per share over the period commencing on April 11, 2013 and ending on May 24, 2013.

These values exclude the potential for up to approximately $4.70 per share related to the CVRs. The CVRs provide each holder thereof the right to receive such payments as described in "The CVRs" beginning on page 76.

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Q.

How does the Company's board of directors recommend that I vote?

A.

The board of directors unanimously recommends that you vote "FOR" approval of the proposal to adopt the merger agreement, "FOR" approval of the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies and "FOR" approval of the proposal to approve, by non-binding, advisory vote, certain compensation arrangements for the Company's named executive officers in connection with the merger.

Q.

When do you expect the merger to be completed?

A.

We are working towards completing the merger as soon as possible. Assuming timely receipt of required regulatory approvals and satisfaction of other closing conditions, including approval by our stockholders of the proposal to adopt the merger agreement, we anticipate that the merger will be completed in the third quarter of 2013.

Q.

What happens if the merger is not completed?

A.

If the merger agreement is not adopted by the stockholders of the Company or if the merger is not completed for any other reason, the stockholders of the Company will not receive any payment for their shares of Company common stock in connection with the merger. Instead, the Company will remain an independent public company and Company common stock will continue to be listed and traded on the NASDAQ Global Market. Under specified circumstances, the Company may be required to pay to Parent a fee with respect to the termination of the merger agreement, as described under "The Merger Agreement—Termination Fees and Expenses" beginning on page 72.

Q.

What happens if the proposal to approve, by non-binding, advisory vote, certain compensation arrangements for the Company's named executive officers in connection with the merger is not approved?

A.

Approval of the compensation that may be paid or become payable to the Company's named executive officers that is based on or otherwise related to the merger is not a condition to the completion of the merger. The vote is advisory only and will not be binding on the Company or Parent. Even though the Company values the input of stockholders as to whether such compensation is appropriate, if the merger is approved by the stockholders and completed, the Company will have a contractual obligation to pay such compensation to its named executive officers if, as and when it becomes due even if the compensation is not approved by the stockholders in the advisory vote.

Q.

What conditions must be satisfied to complete the merger?

A.

In addition to approval of the adoption of the merger agreement by the affirmative vote of the holders of a majority of the outstanding shares of Company common stock entitled to vote thereon, each of the other closing conditions contained in the merger agreement must be satisfied or waived, including, but not limited to, the absence of any event or occurrence or development of a circumstance, in each case arising after the date of the merger agreement which, individually or in the aggregate, has had or would reasonably be expected to have a material adverse effect on the Company (as defined below).

For a more complete summary of the conditions that must be satisfied or waived prior to the completion of the merger, see "The Merger Agreement—Conditions to the Merger" beginning on page 69.

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Q.

What are the U.S. federal income tax consequences of the merger?

A.

The exchange of shares of Company common stock for cash and CVRs in the merger will generally be a taxable transaction to U.S. holders for U.S. federal income tax purposes. In general, a U.S. holder whose shares of Company common stock are converted into the right to receive cash and CVRs in the merger will recognize gain or loss for U.S. federal income tax purposes in an amount equal to the difference, if any, between the amount of the cash consideration received with respect to such shares and the U.S. holder's adjusted tax basis in such shares.

There is substantial uncertainty as to the tax treatment of the CVRs. The U.S. federal income tax treatment of the receipt of, and payment with respect to, the CVRs depends on whether the receipt of the CVRs is treated as a "closed transaction" or an "open transaction" for U.S. federal income tax purposes. You should read "The Merger—Material U.S. Federal Income Tax Consequences of the Merger" beginning on page 51 for a more detailed discussion of the U.S. federal income tax consequences of the merger, including the receipt of, and payments with respect to, the CVRs. Tax matters can be complicated and the tax consequences of the merger to you will depend on your particular tax situation. You should consult your tax advisor to determine the tax consequences of the merger to you.

Q.

Do any of the Company's directors or officers have interests in the merger that may differ from or be in addition to my interests as a stockholder?

A.

Yes. In considering the recommendation of the board of directors to adopt the merger agreement, you should be aware that the Company's directors and executive officers have interests in the merger that may be different from, or in addition to, the interests of our stockholders generally. The board of directors was aware of these interests and considered them, among other matters, in evaluating the merger agreement, in reaching its decision to approve the merger agreement, and in recommending to the Company's stockholders that the merger agreement be adopted. See "The Merger—Interests of Certain Persons in the Merger" beginning on page 47 and "Advisory Vote on Merger-Related Compensation for the Company's Named Executive Officers" beginning on page 82.

Q.

Why am I receiving this proxy statement and proxy card or voting instruction form?

A.

You are receiving this proxy statement and proxy card or voting instruction form because you own shares of Company common stock. This proxy statement describes matters on which we urge you to vote and is intended to assist you in deciding how to vote your shares of Company common stock with respect to such matters.

Q.

When and where is the special meeting?

A.

The special meeting of stockholders of the Company will be held on July 16, 2013 at 9:00 a.m. Eastern time, at The Westin Princeton at Forrestal Village, 201 Village Boulevard, Princeton, NJ 08540.

Q.

What am I being asked to vote on at the special meeting?

A.

You are being asked to consider and vote on a proposal to adopt the merger agreement that provides for the acquisition of the Company by Parent, to approve a proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the special meeting to approve the proposal to adopt the merger agreement, and to approve a proposal to approve, by non-binding, advisory vote, certain compensation arrangements for the Company's named executive officers in connection with the merger.

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Q.

What vote is required for the Company's stockholders to approve the proposal to adopt the merger agreement?

A.

The adoption of the merger agreement requires the affirmative vote of the holders of a majority of the outstanding shares of Company common stock entitled to vote thereon.

Because the affirmative vote required to approve the proposal to adopt the merger agreement is based upon the total number of outstanding shares of Company common stock present in person or represented by proxy, if you fail to submit a proxy or vote in person at the special meeting, or abstain, or you do not provide your bank, brokerage firm or other nominee with instructions, as applicable, this will have the same effect as a vote "AGAINST" approval of the proposal to adopt the merger agreement.

In connection with the merger agreement, the committed stockholders entered into the voting agreements, pursuant to which such committed stockholders agreed, among other things, to vote their shares of Company common stock, representing approximately 60% of the issued and outstanding shares of Company common stock as of June 12, 2013, the latest practicable date before the printing of this proxy statement, in favor of the proposal to adopt the merger agreement, subject to the terms and conditions set forth in the voting agreements. Accordingly, unless the voting agreements are terminated in accordance with their terms, the committed stockholders will vote their shares of Company common stock in favor of adopting the merger agreement and the adoption of the merger agreement will be approved.

Q.

What vote of our stockholders is required to approve the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies?

A.

Approval of the proposal to adjourn the special meeting, if necessary or appropriate, for the purpose of soliciting additional proxies requires the affirmative vote of the holders of a majority of the shares of Company common stock present in person or represented by proxy and entitled to vote on the matter at the special meeting, whether or not a quorum is present.

Abstaining will have the same effect as a vote "AGAINST" approval of the proposal to adjourn the special meeting, if necessary or appropriate, for the purpose of soliciting additional proxies. If you fail to submit a proxy or to vote in person at the special meeting or if your shares of Company common stock are held through a bank, brokerage firm or other nominee and you do not instruct your bank, brokerage firm or other nominee to vote your shares of Company common stock, your shares of Company common stock will not be voted, but this will not have an effect on the proposal to adjourn the special meeting.

Q.

What vote of our stockholders is required to approve the proposal to approve, by non-binding, advisory vote, certain compensation arrangements for the Company's named executive officers in connection with the merger?

A.

Approving the merger-related compensation for named executive officers requires the affirmative vote of a majority of votes properly cast by stockholders entitled to vote at the special meeting on the proposal to approve such merger-related compensation.

Accordingly, abstentions, broker non-votes and shares not in attendance at the special meeting will have no effect on the outcome of any vote to approve the merger-related executive compensation.

Q.

What is the difference between holding shares as a stockholder of record and as a beneficial owner?

A.

If your shares are registered directly in your name with our transfer agent, American Stock Transfer & Trust Company, you are considered the stockholder of record with respect to those

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shares. As the stockholder of record, you have the right to vote, grant your voting proxy directly to the Company or to a third party or to vote in person at the meeting.

If your shares are held by a bank, broker, trustee or nominee, you are considered the beneficial owner of shares held in "street name," and your bank or broker is considered the stockholder of record with respect to those shares. Your bank, broker, trustee or nominee will send you, as the beneficial owner, a package describing the procedure for voting your shares. You should follow the instructions provided by them to vote your shares. You are invited to attend the special meeting if you bring a copy of your brokerage statement evidencing your beneficial ownership of Company common stock and valid photo identification; however, you may not vote these shares in person at the meeting unless you obtain a "legal proxy" from your bank, broker, trustee or nominee that holds your shares, giving you the right to vote the shares at the meeting.

Q.

If my shares of Company common stock are held in "street name" by my bank, brokerage firm or other nominee, will my bank, brokerage firm or other nominee vote my shares of Company common stock for me?

A.

Your bank, brokerage firm or other nominee will only be permitted to vote your shares of Company common stock if you instruct your bank, brokerage firm or other nominee how to vote. You should follow the procedures provided by your bank, brokerage firm or other nominee regarding the voting of your shares of Company common stock. Under the rules applicable to broker-dealers, banks, brokerage firms or other nominees who hold shares in street name for customers have the authority to vote on routine proposals when they have not received instructions from beneficial owners. However, banks, brokerage firms and other nominees are precluded from exercising their voting discretion with respect to approving non-routine matters, such as the proposal to adopt the merger agreement, and, as a result, absent specific instructions from the beneficial owner of such shares of Company common stock, banks, brokerage firms or other nominees are not empowered to vote those shares of Company common stock on non-routine matters. If you do not instruct your bank, brokerage firm or other nominee to vote your shares of Company common stock, your shares of Company common stock will not be voted, which we refer to as broker non-votes, and the effect will be the same as a vote "AGAINST" approval of the proposal to adopt the merger agreement, and your shares of Company common stock will not have an effect on the proposal to adjourn the special meeting or on the proposal to approve the merger-related executive compensation.

Q.

Who can vote at the special meeting?

A.

All of the holders of record of Company common stock as of the close of business on June 13, 2013, the record date for the special meeting, are entitled to receive notice of, and to attend and vote at, the special meeting. Each holder of Company common stock is entitled to cast one vote on each matter properly brought before the special meeting for each share of Company common stock that such holder owned as of the record date.

Q.

How many votes do I have?

A.

You are entitled to one vote for each share of the Company common stock held of record as of the record date, which is June 13, 2013. As of close of business on the record date, there were 24,414,171 outstanding shares of Company common stock.

Q.

What is a quorum?

A.

A majority of the shares of Company common stock outstanding at the close of business on the record date and entitled to vote, present in person or represented by proxy, at the special meeting constitutes a quorum for the purposes of the special meeting. There must be a quorum for

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business to be conducted at the special meeting. Abstentions will be counted as present for the purpose of determining whether a quorum is present. Broker non-votes will not be counted as present for the purpose of determining whether a quorum is present.

Q.

How do I vote?

A.

Stockholder of Record .    If you are a stockholder of record, you may have your shares of Company common stock voted on matters presented at the special meeting in any of the following ways:

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in person—you may attend the special meeting and cast your vote there; or

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by proxy—stockholders of record have a choice of voting by proxy (i) by signing, dating and returning the enclosed proxy card in the accompanying prepaid reply envelope or (ii) over the Internet or by telephone by following the instructions on your proxy card.

A control number, located on your proxy card, is designed to verify your identity and allow you to vote your shares of Company common stock, and to confirm that your voting instructions have been properly recorded when voting over the Internet or by telephone. Please be aware that if you vote over the Internet, you may incur costs such as telephone and Internet access charges for which you will be responsible.

Beneficial Owner.     If you are a beneficial owner, please refer to the instructions provided by your bank, brokerage firm or other nominee to see which of the above choices are available to you. Please note that if you are a beneficial owner and wish to vote in person at the special meeting, you must provide a legal proxy from your bank, brokerage firm or other nominee at the special meeting.

Q.

How can I change or revoke my vote?

A.

You have the right to revoke a proxy before it is voted by submitting a new proxy card with a later date or subsequently voting via telephone or the Internet. Record holders may also revoke their proxy by voting in person at the special meeting or by notifying the Company's Secretary in writing at: Omthera Pharmaceuticals, Inc., Attention: Corporate Secretary, 707 State Road, Princeton, New Jersey 08540.

Q.

What is a proxy?

A.

A proxy is your legal designation of another person, referred to as a "proxy," to vote your shares of Company common stock. The written document describing the matters to be considered and voted on at the special meeting is called a "proxy statement." The document used to designate a proxy to vote your shares of Company common stock is called a "proxy card."

Q.

If a stockholder gives a proxy, how are the shares of Company common stock voted?

A.

The individuals named on the enclosed proxy card, or your proxies, will vote your shares of Company common stock in the way that you indicate. When completing the Internet or telephone processes or the proxy card, you may specify whether your shares of Company common stock should be voted for or against or to abstain from voting on all, some or none of the specific items of business to come before the special meeting.

If you properly sign your proxy card but do not mark the boxes showing how your shares should be voted on a matter, the shares represented by your properly signed proxy will be voted "FOR" approval of the proposal to adopt the merger agreement, "FOR" approval of the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies and "FOR" approval of the proposal to approve, by non-binding, advisory vote, certain compensation arrangements for the Company's named executive officers in connection with the merger.

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Q.

How are votes counted?

A.

For the proposal to adopt the merger agreement, you may vote "FOR," "AGAINST" or "ABSTAIN." Abstentions and broker non-votes will have the same effect as votes "AGAINST" approval of the proposal to adopt the merger agreement.

For the proposal to adjourn the special meeting, if necessary or appropriate, you may vote "FOR," "AGAINST" or "ABSTAIN." Abstentions will have the same effect as if you voted "AGAINST" approval of the proposal, but broker non-votes will not have an effect on the proposal.

For the proposal to approve the merger-related executive compensation, you may vote "FOR," "AGAINST" or "ABSTAIN." Abstentions and broker non-votes will not have an effect on the proposal.

Q.

What do I do if I receive more than one proxy or set of voting instructions?

A.

If you hold shares of Company common stock in "street name" and also directly as a record holder or otherwise, you may receive more than one proxy and/or set of voting instructions relating to the special meeting. Please vote each proxy or voting instruction card in accordance with the instructions provided in this proxy statement in order to ensure that all of your shares of Company common stock are voted.

Q.

What happens if I sell my shares of Company common stock before the special meeting?

A.

The record date for stockholders entitled to vote at the special meeting is earlier than both the date of the special meeting and the consummation of the merger. If you transfer your shares of Company common stock after the record date but before the special meeting, unless special arrangements (such as provision of a proxy) are made between you and the person to whom you transfer your shares and each of you notifies the Company in writing of such special arrangements, you will retain your right to vote such shares at the special meeting but will transfer the right to receive the merger consideration to the person to whom you transfer your shares.

Q.

What happens if I sell my shares of Company common stock after the special meeting but before the effective time of the merger?

A.

If you transfer your shares after the special meeting but before the effective time of the merger, you will have transferred the right to receive the merger consideration to the person to whom you transfer your shares. In order to receive the merger consideration, you must hold your shares of Company common stock through completion of the merger.

Q.

Where can I find the voting results of the special meeting?

A.

The Company intends to announce preliminary voting results at the special meeting and publish final results in a Current Report on Form 8-K that will be filed with the SEC following the special meeting. All reports the Company files with the SEC are publicly available when filed.

Q.

Who will solicit and pay the cost of soliciting proxies?

A.

The Company has engaged MacKenzie Partners, Inc., which we refer to as MacKenzie, to assist in the solicitation of proxies for the special meeting. The Company estimates that it will pay MacKenzie a fee of $20,000, plus telephone and mailing charges. The Company has agreed to reimburse MacKenzie, pay directly, or, where requested in special situations, advance sufficient funds to MacKenzie, for the payment of certain fees and expenses and will also indemnify MacKenzie, its subsidiaries and their respective directors, officers, employees and agents against certain claims, liabilities, losses, damages and expenses. The Company may also reimburse banks, brokers or their agents for their expenses in forwarding proxy materials to beneficial owners of

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Company common stock. Our directors, officers and employees may also solicit proxies by telephone, by facsimile, by mail, on the Internet or in person. They will not be paid any additional amounts for soliciting proxies.

Q.

What do I need to do now?

A.

Even if you plan to attend the special meeting, after carefully reading and considering the information contained in this proxy statement, please vote promptly to ensure that your shares are represented at the special meeting. If you hold your shares of Company common stock in your own name as the stockholder of record, please submit a proxy to have your shares of Company common stock voted at the special meeting (i) by completing, signing, dating and returning the enclosed proxy card in the accompanying prepaid reply envelope or (ii) over the Internet or by telephone by following the instructions on your proxy card. If you decide to attend the special meeting and vote in person, your vote by ballot will revoke any proxy previously submitted. If you are a beneficial owner, please refer to the instructions provided by your bank, brokerage firm or other nominee to see which of the above choices are available to you.

Q.

How will I exchange my shares for the merger consideration?

A.

If the proposal to adopt the merger agreement is approved, you will be sent a letter of transmittal and instructions promptly after the effective time of the merger, and in any event no later than the second business day following the closing, describing how you may exchange your shares of Company common stock for the merger consideration. If your shares of Company common stock are held in "street name" through a bank, brokerage firm or other nominee, you will receive instructions from your bank, brokerage firm or other nominee as to how to effect the surrender of your "street name" shares of Company common stock in exchange for the merger consideration.

Q.

Am I entitled to exercise appraisal rights under the DGCL instead of receiving the per share merger consideration for my shares of Company common stock?

A.

Yes. As a holder of Company common stock, you are entitled to exercise appraisal rights under the DGCL in connection with the merger if you take certain actions, meet certain conditions, and fully comply with the requirements set forth under the DGCL, including that you do not vote (in person or by proxy) in favor of adoption of the merger agreement. See "Appraisal Rights" beginning on page 86.

Q.

How can I obtain additional information about the Company?

A.

Any person, including any beneficial owner, to whom this proxy statement is delivered may request copies of proxy statements and any of the documents incorporated by reference in this document or other information concerning us, without charge, by written or telephonic request directed to Omthera Pharmaceuticals, Inc., Attn: Christian S. Schade, 707 State Road, Princeton, New Jersey 08540, Telephone (908) 741-4399; or MacKenzie Partners, Inc., our proxy solicitor, toll-free at (800) 322-2885 or collect at (212) 929-5500; or from the SEC through the SEC's website at http://www.sec.gov . Documents incorporated by reference are available without charge, excluding any exhibits to those documents unless the exhibit is specifically incorporated by reference into those documents. For further information, see "Where You Can Find More Information" beginning on page 92.

Q.

Who can help answer any other questions I might have?

A.

If you have additional questions about the merger, need assistance in submitting your proxy or voting your shares of Company common stock, or need additional copies of the proxy statement or the enclosed proxy card, please contact MacKenzie Partners, Inc., our proxy solicitor, by calling toll-free at (800) 322-2885 or collect at (212) 929-5500.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

        This proxy statement, and the documents to which we refer you in this proxy statement, as well as oral statements made or to be made by us, contain certain "forward-looking" statements as that term is defined by Section 27A of the Securities Act of 1933, as amended, which we refer to as the Securities Act, and Section 21E of the Exchange Act. Statements that are predictive in nature, that depend on or relate to future events or conditions, or that include words such as "believes," "anticipates," "expects," "continues," "predict," "potential," "contemplates," "may," "will," "likely," "could," "should," "estimates," "intends," "plans" and other similar expressions are forward-looking statements. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. Forward-looking statements involve known and unknown risks, assumptions and uncertainties that may cause our actual results in future periods to differ materially from those projected or contemplated in the forward-looking statements as a result of, but not limited to, the following factors:

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the occurrence of any event, change or other circumstances that could give rise to the termination of the merger agreement, including a termination of the merger agreement under circumstances that could require us to pay a termination fee;



•

the inability to complete the merger due to the failure to obtain stockholder approval or the failure to satisfy other conditions to completion of the merger, including receipt of required regulatory approvals;



•

the Company's and Parent's ability to consummate the merger;



•

the failure of the merger to close for any other reason;



•

the ability of Parent to achieve the milestones on the terms specified in the CVR agreement;



•

risks that the proposed transaction disrupts current plans and operations and the potential difficulties in retention of executive management and other key employees as a result of the merger;



•

the outcome of any legal proceedings that have been or may be instituted against the Company and/or others relating to the merger agreement, and the transactions contemplated thereby, including the merger;



•

diversion of management's attention from ongoing business concerns;



•

limitations placed on our ability to operate the business by the merger agreement;



•

the effect of the announcement of the merger on our business relationships, standing with regulators, operating results and business generally;



•

the amount of the costs, fees, expenses, impairments and charges related to the merger;



•

the risk that the transactions contemplated by the merger agreement may not be completed in the time frame expected by the parties or at all;



•

the difficulty of integrating the business, operations and employees of the Company and Parent; and



•

certain presently unknown or unforeseen factors, including, but not limited to, acts of terrorism and natural disasters.

        Additional information about these factors and about the material factors or assumptions underlying such forward-looking statements may be found under the headings "Risk Factors" and "Business," and information in our consolidated financial statements and notes thereto, included in the Company's Prospectus filed pursuant to Rule 424(b)(4) of the Securities Act with the SEC on April 12,

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2013 in connection with the Company's initial public offering and the Company's quarterly report on Form 10-Q for the period ended March 31, 2013 (see the section entitled "Where You Can Find More Information" beginning on page 92). The Company cautions that the foregoing list of important factors that may affect future results is not exhaustive. When relying on forward-looking statements to make decisions with respect to the proposed transaction, stockholders and others should carefully consider the foregoing factors and other uncertainties and potential events. All subsequent written and oral forward-looking statements concerning the proposed transaction or other matters attributable to the Company or any other person acting on its behalf are expressly qualified in their entirety by the cautionary statements referenced above. The forward-looking statements contained herein speak only as of the date of this communication. Any or all of the Company's forward-looking statements may turn out to be wrong. They can be affected by inaccurate assumptions or by known or unknown risks, uncertainties and other factors, many of which are beyond the Company's control. The Company undertakes no obligation to update or revise and forward-looking statements for any reason, even if new information becomes available or other events occur in the future, except as may be required by law.

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PARTIES TO THE MERGER

The Company

Omthera Pharmaceuticals, Inc.
707 State Road
Princeton, New Jersey 08540
(908) 741-4399

        The Company, a corporation organized under the laws of Delaware, is an emerging specialty pharmaceutical company focused on the development and commercialization of new therapies for abnormalities in blood lipids, referred to as dyslipidemia, and the treatment of cardiovascular disease. Epanova™, currently the Company's sole product candidate, is a late-stage, novel, omega-3 free fatty acid composition that meaningfully reduces triglycerides, improves other key lipid parameters and is expected to increase patient convenience with 2-gram once-a-day dosing with or without meals. Based on the Company's clinical experience to date, we expect to submit a New Drug Application with the U.S. Food and Drug Administration in mid-2013 to commercialize Epanova™ in the United States for treatment of patients with triglyceride levels greater than or equal to 500 mg/dL, or severe hypertriglyceridemia.

        For more information about the Company, please visit its website at http://www.omthera.com . The Company's website address is provided as an inactive textual reference only. The information contained on the Company's website is not incorporated into, and does not form a part of, this proxy statement or any other report or document on file with or furnished to the SEC. See also "Where You Can Find More Information" beginning on page 92.

        The Company common stock is listed on the NASDAQ Global Market under the symbol "OMTH."

AstraZeneca

AstraZeneca PLC
2 Kingdom Street
London, England W2 6BD, United Kingdom
+44 20 7604 8000

        AstraZeneca PLC, a U.K. public limited company is engaged in the discovery, development and commercialization of pharmaceutical products.

        For more information about AstraZeneca PLC, please visit its website at http://www.astrazeneca.com/ . AstraZeneca PLC's website address is provided as an inactive textual reference only. The information contained on its website is not incorporated into, and does not form a part of, this proxy statement or any other report or document on file with or furnished to the SEC.

Parent

Zeneca, Inc.
1800 Concord Pike
Wilmington, Delaware 19803
(800) 236-9933

        Zeneca, Inc., a Delaware corporation and wholly owned indirect subsidiary of AstraZeneca is engaged in the business of managing certain assets and liabilities of the AstraZeneca group.

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Merger Subsidiary

KAFA Acquisition Corp .
1800 Concord Pike
Wilmington, Delaware 19803
(800) 236-9933

        KAFA Acquisition Corp., a Delaware corporation and wholly owned subsidiary of Parent, was incorporated in May 2013 solely for the purpose of facilitating the merger. Merger Subsidiary has not carried on any activities to date, except for activities incidental to its formation and activities undertaken in connection with the transactions contemplated by the merger agreement.

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THE SPECIAL MEETING

Date, Time, Place and Purpose of the Special Meeting

        This proxy statement is being furnished to our stockholders as part of the solicitation of proxies by the board of directors for use at the special meeting to be held on July 16, 2013, at 9:00 a.m. Eastern time, at The Westin Princeton at Forrestal Village, 201 Village Boulevard, Princeton, NJ 08540, or at any postponement or adjournment thereof. At the special meeting, holders of Company common stock will be asked to approve the proposal to adopt the merger agreement, to approve the proposal to adjourn the special meeting, if necessary or appropriate, for the purpose of soliciting additional proxies if there are insufficient votes at the time of the special meeting to approve the proposal to adopt the merger agreement and to approve the proposal to approve, by non-binding, advisory vote, certain compensation arrangements for the Company's named executive officers in connection with the merger.

        Our stockholders must approve the proposal to adopt the merger agreement in order for the merger to occur. If our stockholders fail to approve the proposal to adopt the merger agreement, the merger will not occur. A copy of the merger agreement is attached as Annex A to this proxy statement, which we encourage you to read carefully and in its entirety.

Recommendation of the Company's Board of Directors

        After careful consideration, the Company's board of directors unanimously determined that the terms of the merger are advisable and in the best interests of the Company and its stockholders and unanimously approved the merger agreement and the merger. Certain factors considered by the Company's board of directors in reaching its decision to approve the merger agreement and the merger can be found in the section entitled "The Merger—Reasons for the Merger; Recommendation of the Board of Directors" beginning on page 34.

Record Date and Quorum

        We have fixed the close of business on June 13, 2013 as the record date for the special meeting, and only holders of record of Company common stock on the record date are entitled to vote at the special meeting. You are entitled to receive notice of, and to vote at, the special meeting if you owned shares of Company common stock at the close of business on the record date. On the record date, there were 24,414,171 shares of Company common stock outstanding and entitled to vote. You will have one vote on all matters properly coming before the special meeting for each share of Company common stock that you owned on the record date.

        A majority of the shares of Company common stock outstanding at the close of business on the record date and entitled to vote, present in person or represented by proxy, at the special meeting constitutes a quorum for the purposes of the special meeting. Shares of Company common stock represented at the special meeting but not voted, including shares of Company common stock for which a stockholder directs an "abstention" from voting, will be counted for purposes of establishing a quorum. Broker non-votes (as described below) will be counted for purposes of establishing a quorum. A quorum is necessary to transact business at the special meeting. Once a share of Company common stock is represented at the special meeting, it will be counted for the purpose of determining a quorum at the special meeting and any adjournment of the special meeting. However, if a new record date is set for the adjourned special meeting, then a new quorum will have to be established. In the event that a quorum is not present at the special meeting, it is expected that the special meeting will be adjourned.

Attendance

        Only stockholders of record, their duly authorized proxy holders, beneficial stockholders with proof of ownership and our guests may attend the special meeting. Please bring to the special meeting proof

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of your beneficial ownership of Company common stock. Acceptable proof could include an account statement showing that you owned shares of the Company common stock on the record date, June 13, 2013. If you are the representative of a corporate or institutional stockholder, you must present valid photo identification along with proof that you are the representative of such stockholder. Please note that cameras, recording devices and other electronic devices will not be permitted at the special meeting.

Vote Required

        Approval of the proposal to adopt the merger agreement requires the affirmative vote of the holders of a majority of the outstanding shares of Company common stock entitled to vote thereon. The proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies requires the affirmative vote of the holders of a majority of the shares of Company common stock present in person or represented by proxy and entitled to vote on the matter at the special meeting, whether or not a quorum is present. The proposal to approve, by non-binding, advisory vote, certain compensation arrangements for the Company's named executive officers in connection with the merger requires the affirmative vote of a majority of votes properly cast by stockholders entitled to vote on the matter at the special meeting. You may vote "FOR," "AGAINST" or "ABSTAIN" with respect to any proposal.

        Your failure to vote, or failure to instruct your broker, bank or other nominee to vote, will have the same effect as a vote against the proposal to adopt the merger agreement, but will have no effect on the other proposals.

        If you attend the special meeting or send in your signed proxy card, but abstain from voting on any proposal, you will still be counted for purposes of determining whether a quorum exists. If you abstain from voting on the proposal to adopt the merger agreement or the proposal to adjourn the special meeting, your abstention will have the same effect as a vote against such proposal. If you abstain from voting on the proposal to approve the merger-related executive compensation, your abstention will have no effect on such proposal.

        If your shares of Company common stock are registered directly in your name with our transfer agent, American Stock Transfer & Trust Company, you are considered, with respect to those shares of Company common stock, the "stockholder of record." This proxy statement and proxy card have been sent directly to you by the Company.

        If your shares of Company common stock are held through a bank, brokerage firm or other nominee, you are considered the "beneficial owner" of shares of Company common stock held in street name. In that case, this proxy statement has been forwarded to you by your bank, brokerage firm or other nominee who is considered, with respect to those shares of Company common stock, the stockholder of record. As the beneficial owner, you have the right to direct your bank, brokerage firm or other nominee how to vote your shares by following their instructions for voting.

        If you are a stockholder of record, you may have your shares of Company common stock voted on matters presented at the special meeting in any of the following ways:

•

in person—you may attend the special meeting and cast your vote there; or



•

by proxy—stockholders of record have a choice of voting by proxy (i) by completing, signing, dating and returning the enclosed proxy card in the accompanying prepaid reply envelope or (ii) over the Internet or by telephone by following the instructions on your proxy card.

        If you are a beneficial owner, you will receive instructions from your bank, brokerage firm or other nominee that you must follow in order to have your shares of Company common stock voted. Those instructions will identify which of the above choices are available to you in order to have your shares voted. Please note that if you are a beneficial owner and wish to vote in person at the special meeting,

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you must provide a legal proxy from your bank, brokerage firm or other nominee at the special meeting.

        A control number, located on your proxy card, is designed to verify your identity and allow you to vote your shares of Company common stock, and to confirm that your voting instructions have been properly recorded when submitting a proxy over the Internet or by telephone. Please be aware that if you submit a proxy over the Internet, you may incur costs such as telephone and Internet access charges for which you will be responsible.

        Please refer to the instructions on your proxy or voting instruction card to determine the deadlines for voting over the Internet or by telephone. If you choose to submit a proxy by mailing a proxy card, your proxy card should be mailed in the accompanying prepaid reply envelope, and your proxy card must be filed with our Corporate Secretary by the time the special meeting begins. When the merger is completed, a separate letter of transmittal will be mailed to you that will enable you to receive the merger consideration in exchange for your shares of Company common stock.

        If you vote by proxy, regardless of the method you choose to vote, the individuals named on the enclosed proxy card, and each of them, with full power of substitution, or your proxies, will vote your shares of Company common stock in the way that you indicate. When completing the Internet or telephone processes or the proxy card, you may specify whether your shares of Company common stock should be voted for or against or to abstain from voting on all, some or none of the specific items of business to come before the special meeting.

        If you properly sign your proxy card but do not mark the boxes showing how your shares of Company common stock should be voted on a matter, the shares of Company common stock represented by your properly signed proxy will be voted "FOR" approval of the proposal to adopt the merger agreement, "FOR" approval of the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies and "FOR" approval of the proposal to approve, by non-binding, advisory vote, certain compensation arrangements for the Company's named executive officers in connection with the merger.

        If you have any questions or need assistance voting your shares, please contact MacKenzie Partners, Inc., our proxy solicitor, by calling toll-free at (800) 322-2885 or collect at (212) 929-5500.

         IT IS IMPORTANT THAT YOU VOTE YOUR SHARES OF COMPANY COMMON STOCK AT THE MEETING PROMPTLY. WHETHER OR NOT YOU PLAN TO ATTEND THE SPECIAL MEETING, PLEASE COMPLETE, DATE, SIGN AND RETURN, AS PROMPTLY AS POSSIBLE, THE ENCLOSED PROXY CARD IN THE ACCOMPANYING PREPAID REPLY ENVELOPE, OR SUBMIT YOUR PROXY BY TELEPHONE OR THE INTERNET. STOCKHOLDERS WHO ATTEND THE SPECIAL MEETING MAY REVOKE THEIR PROXIES BY VOTING IN PERSON.

        As of June 13, 2013, the record date, the directors and executive officers of the Company beneficially owned and were entitled to vote, in the aggregate, 2,914,781 shares of Company common stock (not including any shares of Company common stock deliverable upon exercise or conversion of any stock options), representing 11.9% of the outstanding shares of Company common stock. The directors and officers have informed the Company that they currently intend to vote all such shares of Company common stock "FOR" approval of the proposal to adopt the merger agreement, "FOR" approval of the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies and "FOR" approval of the proposal to approve, by non-binding, advisory vote, certain compensation arrangements for the Company's named executive officers in connection with the merger, although no director or executive officer has entered into an agreement obligating him to do so except for the voting agreements described below.

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Voting Agreements

        In connection with the merger agreement, the committed stockholders entered into the voting agreements. Pursuant to the voting agreements, the committed stockholders agreed to vote their shares of Company common stock in favor of the merger and against any (i) acquisition proposal (as defined below), (ii) reorganization, recapitalization, liquidation or winding-up of the Company or any other extraordinary transaction involving the Company other than the merger or (iii) corporate action the consummation of which would frustrate the purposes, or prevent or delay the consummation, of the transactions contemplated by the merger agreement. The committed stockholders together own approximately 60% of the issued and outstanding shares of Company common stock as of June 12, 2013, the latest practicable date before the printing of this proxy statement. Accordingly, unless the voting agreements are terminated in accordance with their terms, the committed stockholders will vote their shares of Company common stock in favor of adopting the merger agreement and the adoption of the merger agreement will be approved.

        The voting agreements will terminate upon the earlier of (i) the merger and (ii) the termination of the merger agreement in accordance with its terms. In addition, the committed stockholders may terminate their respective voting agreements if the board of directors changes its recommendation in accordance with the terms of the merger agreement or if the merger agreement is amended to decrease the amount or change the form of the merger consideration.

        The foregoing does not limit, restrict or otherwise affect the committed stockholders or their respective officers, directors, employees, investment bankers, attorneys, accountants, consultants or other agents or advisors in its or their capacity as a director or officer of the Company, or any designee of a committed stockholder who is a director or officer of the Company, from acting in such capacity or voting in such person's sole discretion on any matter.

Proxies and Revocation

        Any stockholder of record entitled to vote at the special meeting may submit a proxy by telephone, over the Internet, by returning the enclosed proxy card in the accompanying prepaid reply envelope, or may vote in person by appearing at the special meeting. If your shares of Company common stock are held in "street name" through a bank, brokerage firm or other nominee, you should instruct your bank, brokerage firm or other nominee on how to vote your shares of Company common stock using the instructions provided by your bank, brokerage firm or other nominee. If you fail to submit a proxy or to vote in person at the special meeting, or do not provide your bank, brokerage firm or other nominee with instructions, as applicable, your shares of Company common stock will not be voted on the proposal to adopt the merger agreement, which will have the same effect as a vote "AGAINST" approval of the proposal to adopt the merger agreement, and your shares of Company common stock will not have an effect on the proposal to adjourn the special meeting or on the proposal to approve the merger-related executive compensation.

        You have the right to revoke a proxy, whether delivered over the Internet, by telephone or by mail, at any time before it is exercised, by voting again at a later date through any of the methods available to you, by giving written notice of revocation to our Corporate Secretary, which must be filed with the Secretary by the time the special meeting begins, or by attending the special meeting and voting in person. Written notice of revocation should be mailed to: Omthera Pharmaceuticals, Inc., Attn: Corporate Secretary, 707 State Road, Princeton, New Jersey 08540.

Adjournments

        Although it is not currently expected, the special meeting may be adjourned for the purpose of soliciting additional proxies if there are insufficient votes at the time of the special meeting to approve the proposal to adopt the merger agreement or if a quorum is not present at the special meeting. Other than an announcement to be made at the special meeting of the time, date and place of an

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adjourned meeting, an adjournment generally may be made with the affirmative vote of the holders of a majority of the shares of Company common stock present in person or represented by proxy and entitled to vote on the matter at the special meeting and without notice. Any adjournment of the special meeting for the purpose of soliciting additional proxies will allow the Company's stockholders who have already sent in their proxies to revoke them at any time prior to their use at the special meeting as adjourned.

Anticipated Date of Completion of the Merger

        We are working towards completing the merger as soon as possible. Assuming receipt of required regulatory approvals and timely satisfaction of other closing conditions, including the approval by our stockholders of the proposal to adopt the merger agreement, we anticipate that the merger will be completed in the third quarter of 2013. If our stockholders vote to approve the proposal to adopt the merger agreement, the merger will become effective as promptly as practicable following the satisfaction or waiver of the other conditions to the merger, subject to the terms of the merger agreement. See "The Merger—Closing and Effective Time of the Merger" beginning on page 46.

Rights of Stockholders Who Seek Appraisal

        Stockholders are entitled to appraisal rights under the DGCL in connection with the merger. This means that you are entitled to have the fair value of your shares of Company common stock determined by the Delaware Court of Chancery and to receive payment based on that valuation in lieu of the merger consideration if you follow exactly the procedures specified under the DGCL. The ultimate amount you receive in an appraisal proceeding may be less than, equal to or more than the amount you would have received under the merger agreement.

        To exercise your appraisal rights, you must submit a written demand for appraisal to the Company before the vote is taken on the merger agreement and you must not vote (either in person or by proxy) in favor of the proposal to adopt the merger agreement. Your failure to follow exactly the procedures specified under the DGCL may result in the loss of your appraisal rights. See "Appraisal Rights" beginning on page 86 and the text of the Delaware appraisal rights statute reproduced in its entirety as Annex D to this proxy statement. If you hold your shares of Company common stock through a bank, brokerage firm or other nominee and you wish to exercise appraisal rights, you should consult with your bank, brokerage firm or other nominee to determine the appropriate procedures for the making of a demand for appraisal by your bank, brokerage firm or other nominee. In view of the complexity of the DGCL, stockholders who may wish to pursue appraisal rights should consult their legal and financial advisors promptly.

Solicitation of Proxies; Payment of Solicitation Expenses

        The Company has engaged MacKenzie to assist in the solicitation of proxies for the special meeting. The Company estimates that it will pay MacKenzie a fee of $20,000, plus telephone and mailing expenses. The Company has agreed to reimburse MacKenzie, pay directly, or, where requested in special situations, advance sufficient funds to MacKenzie, for the payment of certain fees and expenses and will also indemnify MacKenzie, its subsidiaries and their respective directors, officers, employees and agents against certain claims, liabilities, losses, damages and expenses. The Company may also reimburse banks, brokers or their agents for their expenses in forwarding proxy materials to beneficial owners of Company common stock. Our directors, officers and employees may also solicit proxies by telephone, by facsimile, by mail, on the Internet or in person. They will not be paid any additional amounts for soliciting proxies.

Questions and Additional Information

        If you have more questions about the merger or how to submit your proxy, or if you need additional copies of this proxy statement or the enclosed proxy card or voting instructions, please contact MacKenzie Partners, Inc., our proxy solicitor, by calling toll-free at (800) 322-2885 or collect at (212) 929-5500.

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THE MERGER

         This discussion of the merger contained in this section is qualified in its entirety by reference to the complete text of the merger agreement, which is attached to this proxy statement as Annex A , and the form of CVR agreement, which is attached to this proxy statement as Annex C , each of which are incorporated by reference into this proxy statement. We encourage you to read the merger agreement and the form of CVR agreement carefully as they are the legal documents governing the merger.

        The merger agreement provides that Merger Subsidiary will merge with and into the Company. The Company will be the surviving corporation in the merger and will continue to do business following the merger. As a result of the merger, the Company will cease to be a publicly traded company. You will not own any shares of the capital stock of the surviving corporation.

Merger Consideration

        In the merger, each outstanding share of Company common stock (other than excluded shares) will be converted into the right to receive the cash consideration plus a CVR representing the right to receive up to approximately $4.70 in cash in the aggregate, without interest, less any applicable withholding taxes, if specified milestones are achieved within agreed upon time periods, subject to and in accordance with the terms and conditions of the CVR agreement.

Background of the Merger

        The board of directors and senior management of the Company over the past several years have reviewed the Company's long-term strategic plan and potential strategic alternatives, all with the goal of maximizing stockholder value. The Company from time to time has discussed with third parties, including AstraZeneca, potential strategic transactions involving the Company.

        At various times between January 2011 and January 2012, representatives of the Company discussed with Mr. Mahmood Ladha, AstraZeneca's Executive Director, Regional and Corporate Business Development, and/or Will Mongan, AstraZeneca's Executive Director of U.S. Business Development, Epanova ^TM and, on occasion, possible transactions between the companies. The companies entered into a confidentiality agreement in February 2011, but the discussions did not proceed to the negotiation of a transaction.

        On July 18, 2012, at a time when the Company was privately held, the board of directors authorized senior management to work with Goldman Sachs and another nationally recognized financial advisor to identify potential parties that might be interested in and capable of consummating a potential strategic transaction with the Company, and to solicit such parties' interest with respect to such a transaction. At the direction of the board of directors, Goldman Sachs and the other financial advisor contacted approximately 30 potential parties. Five parties (not including AstraZeneca) conducted a due diligence investigation of the Company, including, in some cases, meetings with senior management of the Company. Through the first quarter of 2013, prior to the Company's initial public offering, representatives of the Company or its advisors from time to time discussed with several other third parties possible strategic transactions, including a sale of the Company or a partnering transaction. No such discussions led to a formal proposal by any of such third parties, none of which remain subject to standstill provisions with respect to the Company.

        From July 2012 through October 2012, representatives of the Company discussed with Mr. Ladha and/or Mr. Mongan Epanova and AstraZeneca's potential interest in a transaction with the Company. These discussions did not proceed to the negotiation of a potential transaction.

        During the first quarter of 2013, representatives of the Company again discussed with Mr. Ladha and/or Mr. Mongan from time to time the status of Epanova ^TM and AstraZeneca's potential interest in

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a transaction with the Company. These discussions did not proceed to the negotiation of a potential transaction.

        On April 10, 2013, the day before the Company planned to proceed with its proposed initial public offering, Mr. Ladha contacted Mr. Wisler and inquired whether the board of directors would be willing to consider a potential acquisition by AstraZeneca of the Company or a potential licensing transaction. The board of directors discussed with management that the Company could not postpone or cancel its initial public offering without an alternative source of immediate financing. At the direction of the board of directors, Mr. Wisler informed Mr. Ladha that the Company would consider postponing the initial public offering and engage in discussions about a potential transaction only if AstraZeneca was prepared to make an equity investment in the Company immediately. Mr. Ladha indicated that AstraZeneca was not prepared at that time to consummate an investment in the Company.

        On April 11, 2013, the Company proceeded with its initial public offering at $8.00 per share.

        On April 13, 2013, Mr. Ladha contacted Mr. Wisler to express AstraZeneca's continued interest in a potential transaction involving the Company. On the same day, Mr. Pascal Soriot, the Chief Executive Officer of AstraZeneca, contacted Mr. Wisler, and the following day Mr. Wisler and Mr. Soriot had dinner and discussed the status of Epanova, but did not discuss any details relating to a potential transaction between the companies.

        On April 16, 2013, Mr. Wisler, Christian S. Schade, the Company's Executive Vice President and Chief Financial Officer, and a representative from Goldman Sachs met with Mr. Ladha, at which meeting Mr. Ladha, on behalf of AstraZeneca, offered to acquire the Company for $215 million in cash upfront, representing approximately $8.50 per share of our common stock, and up to $180 million, representing approximately $7.06 per share of our common stock, in the form of a contingent value right payable upon FDA approval for the commercialization of both (x) a product that contains both Crestor and Epanova ^TM as its sole active ingredients, co-formulated in a single, fixed dose combination product and (y) Epanova ^TM in combination with statins as a therapy for hypertriglyceridemia in patients with triglyceride levels greater than 200 mg/dL and less than 500 mg/dL, which we refer to collectively as the "FDC/HTG Milestone". The offer was subject to, among other things, due diligence, the negotiation and execution of mutually acceptable definitive agreements and approval of AstraZeneca's board of directors. AstraZeneca also requested a period of 30 days during which the companies would negotiate exclusively concerning a potential transaction, which request the Company ultimately did not grant.

        On April 17, 2013, the board of directors approved the re-engagement of Goldman Sachs to act as financial advisor in connection with the offer and any other potential transaction involving the Company. The board of directors discussed with management and the Company's advisors various aspects of the proposed offer from AstraZeneca and determined that it would be in the interests of the stockholders of the Company for senior management of the Company, along with the Company's advisors, to further evaluate a potential transaction with AstraZeneca. The board of directors instructed Goldman Sachs to inform AstraZeneca that it was willing to discuss a potential transaction, but that the proposed offer was financially inadequate, that AstraZeneca would need to increase the consideration being offered and that a greater portion of the total consideration should be paid upfront in cash. At the direction of the board of directors, representatives of Goldman Sachs informed AstraZeneca of the foregoing.

        On April 18, 2013, Mr. Ladha communicated to representatives of Goldman Sachs a revised offer for the acquisition of the Company consisting of $280 million in cash upfront, plus a special dividend to stockholders of the Company of the entire cash balance of the Company at closing, representing in the aggregate an estimated $13.49 per share of our common stock, assuming a cash dividend of approximately $63 million, representing approximately $2.47 per share of our common stock, and up to $100 million, representing approximately $3.92 per share of our common stock, in the form of a

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contingent value right payable upon the achievement of the FDC/HTG Milestone. The board of directors discussed with management and the Company's advisors various aspects of AstraZeneca's revised offer. Dr. Michael Davidson, the Company's Chief Medical Officer, called Mr. Pascal Soriot, the Chief Executive Officer of AstraZeneca. During the conversation, Mr. Soriot inquired about Dr. Davidson's willingness to continue working on the development of Epanova following the closing of the Merger, although no specific financial terms of his potential continuing engagement were discussed.

        On April 19, 2013, Mr. Ladha contacted a representative of Goldman Sachs and indicated that, unless the board of directors agreed by 12:00 P.M. Eastern Standard Time that day to move forward to the next stage of discussions based on the April 18 offer, AstraZeneca would terminate discussions with the Company. On that same day, the board of directors discussed with management and the Company's advisors various aspects of AstraZeneca's offer, including the structure of the contingent value right and the potential achievability of the milestones. Following such discussion, the board of directors instructed representatives of Goldman Sachs to inform Mr. Ladha that the structure of the contingent value right needed to be modified, such that 30% of the $100 million contingent value right be payable upon receipt of FDA approval of a new drug application for Epanova ^TM , which we refer to as the "FDA Approval Milestone", with the remainder to be payable upon achievement of the FDC/HTG Milestone. At the direction of the board of directors, representatives of Goldman Sachs informed Mr. Ladha of the foregoing proposal. On the basis of this understanding, the Company permitted AstraZeneca to commence its due diligence investigation of the Company. Later in the same day, the Company sent to AstraZeneca a draft confidentiality agreement, containing a customary 12-month standstill provision, which the parties entered into on April 22, 2013.

        From April 22, 2013 until May 8, 2013, AstraZeneca conducted a due diligence investigation of the Company, including meetings and telephone calls with representatives of the Company and its advisors. On April 24, 2013, the board of directors discussed with management and the Company's advisors whether to contact other potential acquirers and determined that, given the importance of confidentiality in light of the potential adverse effect that could arise if rumors were to surface that the Company and AstraZeneca were discussing a potential transaction, representatives of Goldman Sachs should contact a limited number of potential bidders. The board of directors, in conjunction with management and the Company's advisors, identified two parties, which because of their demonstrated prior interest, prior due diligence investigation and prior discussions, the board of directors and management determined would be most likely to be interested in pursuing a potential transaction involving the Company.

        On May 9, 2013, Mr. Ladha contacted a representative of Goldman Sachs to indicate that AstraZeneca was continuing its internal discussions regarding the results of its due diligence investigation and the proposed transaction terms. On the same day, Mr. Soriot called Dr. Davidson confirming the same message.

        On May 10, 2013, Mr. Ladha contacted a representative of Goldman Sachs to convey a further revised offer consisting of $240 million in cash upfront, plus a special dividend to stockholders of the Company of the entire cash balance of the Company at closing, representing in the aggregate an estimated $11.92 per share of our common stock, assuming a cash dividend of approximately $63 million, representing approximately $2.47 per share of our common stock, and up to $140 million, representing up to approximately $5.49 per share of our common stock, in the form of a contingent value right with the same payment conditions as communicated in its prior offer, except that the FDA Approval Milestone would also be conditioned on the grant by the FDA of a period of five-year new chemical entity (NCE) exclusivity for Epanova ^TM , which combined conditions we refer to as the "NDA/NCE Approval Milestone".

        On May 11, 2013, the board of directors discussed with management and the Company's advisors various aspects of AstraZeneca's revised offer, including the potential achievability of the milestones,

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with the goal of allocating more of the consideration upfront and eliminating the special dividend structure. At the direction of the board of directors, a representative of Goldman Sachs contacted Mr. Ladha to communicate a counterproposal consisting of approximately $323 million in cash upfront (in lieu of the proposed special dividend), representing $12.70 per share of our common stock, and up to $120 million, representing approximately $4.70 per share of our common stock, in the form of a contingent value right, with three milestones: (i) $30 million payable upon FDA approval of a new drug application for Epanova ^TM , (ii) $70 million payable upon achievement of the FDC/HTG Milestone and (iii) $20 million payable upon the earlier of the grant by the FDA of a period of five-year new chemical entity (NCE) exclusivity for Epanova ^TM or the satisfaction of other conditions that provided a similar period of exclusivity. Later on the same day, Mr. Ladha contacted a representative of Goldman Sachs to indicate that AstraZeneca would agree to eliminate the special dividend structure and agree to the $323 million upfront payment, but would not agree to all of the proposed modifications to the contingent value right. Mr. Ladha agreed to the proposal to set the contingent value right at a total of $120 million, with $30 million payable upon the achievement of the NDA/NCE Approval Milestone and $90 million payable on achievement of the FDC/HTG Milestone.

        On May 12, 2013, the board of directors discussed with management and the Company's advisors various aspects of AstraZeneca's revised offer, including the potential achievability of the milestones, with the goal modifying the structure of the contingent value right such that amounts payable in respect of the NDA/NCE Approval Milestone and FDC/HTG Milestone would be payable even if the specific timelines required for payment of such Milestones were not achieved. At the direction of the board of directors, a representative of Goldman Sachs contacted Mr. Ladha to propose the addition of a third milestone providing for payment of the first and second milestone amounts to the extent not otherwise paid if net sales of Epanova ^TM and the fixed dose combination product exceeded $500 million in any consecutive four-quarter period prior to December 31, 2020, which we refer to as the "Net Sales Milestone". Later on the same day, Mr. Ladha indicated that AstraZeneca would accept the Net Sales Milestone but specified that the Net Sales Milestone would apply only if certain elements of the FDC/HTG Milestone had already been achieved.

        On May 13, 2013, the board of directors discussed with management and the Company's advisors AstraZeneca's counter-proposal regarding the Net Sales Milestone and directed representatives of Goldman Sachs to communicate to AstraZeneca that, if AstraZeneca confirmed that it had completed its due diligence investigation of the Company, the board of directors would authorize the negotiation of definitive documentation. The board of directors also discussed with management and the Company's advisors the process for contacting representatives from the two parties previously identified by the board of directors and management on April 24, 2013. On that same day, at the direction of the board of directors of the Company, representatives of Goldman Sachs contacted representatives from such two parties to advise that the Company was considering a potential transaction with a third party and to determine whether they had any interest in discussing an offer to acquire the Company. Shortly after those inquiries, each of such parties responded through Goldman Sachs that they had no interest in pursuing a transaction with the Company at that time. Also on May 13, 2013, AstraZeneca sent to the Company drafts of the merger agreement and voting agreement, and on May 14, AstraZeneca sent to the Company a draft of the CVR agreement. The initial draft merger agreement proposed, among other deal protection provisions, a termination fee of $20 million payable by the Company if the merger agreement were to be terminated under specified circumstances.

        On May 17, 2013, the Company sent to AstraZeneca a revised draft of the merger agreement which, among other things, proposed that the termination fee payable by the Company would be lowered from AstraZeneca's initial proposal of $20 million to an unspecified amount.

        On May 21 and 22, 2013, representatives of the Company, AstraZeneca, and their respective counsel, and Goldman Sachs met to negotiate the drafts of (i) the merger agreement, including with respect to the conditions to closing, the scope of certain covenants and representations and warranties

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to be made by the Company, the scope of the restrictions on the ability of the Company to respond to and negotiate with competing bidders, including the amount of the termination fee payable by the Company, the circumstances under which such fee would be payable and the circumstances under which the Company would be able to terminate the merger agreement, (ii) the CVR agreement, including with respect to the specific requirements of the various milestones and the efforts AstraZeneca would be required to use to achieve such milestones, and (iii) the form of voting agreement, including with respect to the termination provisions.

        On May 23, 2013, after several discussions between the Company, AstraZeneca and their respective counsel, the Company and AstraZeneca agreed to a termination fee of $12.5 million.

        On May 23 and May 24, 2013, counsel to Sofinnova Partners SAS and New Enterprise Associates, Inc. discussed with AstraZeneca's counsel matters with respect to the voting agreement, including the termination provisions. The parties agreed that the voting agreements would terminate automatically upon the termination of the merger agreement and would be terminable by the committed stockholders if the board of directors changed its recommendation or the merger agreement was amended or modified in a manner that decreased the amount or changed the form of the merger consideration.

        On May 24, 2013, the board of directors convened to review the terms of the merger agreement, CVR agreement and voting agreement and related issues, including the potential achievability of the milestones. Also at this meeting, representatives of Goldman Sachs reviewed their preliminary financial analyses with the board of directors.

        On May 27, 2013, the board of directors convened to review the final terms of the merger agreement, CVR agreement and voting agreement and related issues. Also at this meeting, representatives of Goldman Sachs reviewed with the board of directors of the Company its financial analysis of the merger consideration of $12.70 in cash and one CVR and delivered to the board of directors an oral opinion, which opinion was confirmed by delivery of a written opinion dated May 27, 2013, to the effect that, as of that date and based on and subject to various assumptions, matters considered and limitations described in its opinion, the merger consideration of $12.70 in cash and one CVR to be paid to the holders (other than AstraZeneca and its affiliates) of shares of our common stock pursuant to the merger agreement was fair from a financial point of view to such holders. Following further discussion, and after consultation with its advisors, the board of directors unanimously (i) approved the merger agreement, the merger and the other transactions contemplated by the merger agreement, (ii) declared that it is in the best interests of the Company and its stockholders that the Company enter into the merger agreement and consummate the Merger and the other transactions contemplated by the Merger Agreement on the terms and subject to the conditions set forth therein and (iii) declared that the terms of the merger are fair to the Company and its stockholders and (iv) recommended that the stockholders of the Company vote to adopt the merger agreement.

        Before the open of business on May 28, 2013, the Company, Parent and Merger Subsidiary executed the Merger Agreement and announced the transaction in a jointly issued press release.

Reasons for the Merger; Recommendation of the Board of Directors

        The board of directors, at a meeting held on May 27, 2013, unanimously (i) determined that the merger is fair to, and in the best interests of, the company and its stockholders, (ii) approved and declared advisable the merger agreement, the merger and the other transactions contemplated by the merger agreement, (iii) resolved that the merger agreement be submitted for consideration by the stockholders of the Company at a special meeting of stockholders and (iv) recommended that the stockholders of the Company vote to adopt the merger agreement.

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        In evaluating the merger agreement and the merger, the board of directors consulted with the Company's management and legal and financial advisors and, in reaching its decision to approve the merger agreement and to recommend that the Company's stockholders vote for the adoption of the merger agreement, the board of directors considered a variety of factors, including the following:

•

the cash consideration represents a premium of approximately (i) 88% over the closing price per share of Company common stock on May 24, 2013, the last trading day prior to public announcement of the execution of the merger agreement, (ii) 59% over the per share offering price of Company common stock in its initial public offering, and (iii) 78% over the volume weighted average price per share over the period commencing on April 11, 2013 and ending on May 24, 2013 (noting that these values exclude the potential for up to approximately $4.70 per share related to the CVRs, which provide each holder thereof the right to receive such payments as described in the section entitled "The CVRs" beginning on page 76);



•

approximately 73% of the nominal per share merger consideration will be in cash, which provides immediate liquidity and a high degree of certainty of value to the Company's stockholders;



•

the possibility that it could take a considerable period of time, if ever, before the trading price of Company common stock would reach and sustain at least the cash consideration of $12.70;



•

in addition to cash, each Company stockholder will receive CVRs, which may provide Company stockholders an opportunity to realize additional value to the extent the milestones set forth in the CVR agreement are achieved, through additional cash payments under the terms of the CVRs;



•

the board of directors' knowledge and familiarity with the Company's business, financial condition and results of operations, as well as its financial plan and prospects if it were to remain a standalone public company, and the Company's long-term capital needs, which would result in further significant dilution to the stockholders of the Company;



•

the risks inherent in the development and commercialization of therapies for abnormalities in blood lipids, the risks related to clinical data results, approval for marketing by the U.S. Food and Drug Administration, or the FDA, and any potential conditions or contingencies of such approval, and market acceptance, if approved, and other factors affecting the revenues and profitability of biotechnology products generally;



•

the significant risks and considerable costs associated with a successful launch and commercialization by the Company of Epanova™ due, in part, to our lack of any material U.S. and global sales or marketing infrastructure or capabilities;



•

the strategic options available to the Company (including a customary collaboration with or license to another party of Epanova™) and the Company's assessment that none of these options, including remaining as a standalone entity, is likely to present an opportunity that is equal or superior to the merger or to create value for the stockholders that is equal to or greater than that created by the merger in the foreseeable future;



•

trends in the industry in which the Company's business operates and the available strategic alternatives, including remaining a standalone public company or pursuing a transaction with another company in the industry, as well as the risks and uncertainties associated with such alternatives;



•

the assessment by the board of directors regarding the Company's prospects for substantially increasing stockholder value as a standalone company by building a commercial infrastructure, considering (i) the size of the sales force that the Company could reasonably afford to deploy with its financial resources, (ii) the expected growth in product sales given the size of such a

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sales force, (iii) the execution risks associated with transforming an emerging, development-stage company focused on product development into a profitable specialty pharmaceutical company with efficient sales execution and (iv) other risks and uncertainties related to the Company's business plan;

•

the board of directors' view that the sale and negotiation process yielded a full and fair price for the Company;



•

the risk that prolonging the sale and negotiation process further could have resulted in the loss of an opportunity to consummate a transaction with Parent and distracted senior management from implementing the Company's business plan;



•

the reputation of AstraZeneca and its ability to consummate large acquisition transactions on a timely basis;



•

the fact that the committed stockholders, solely in their capacity as stockholders, are supportive of the transaction and have agreed, pursuant to and subject to the conditions of the voting agreements, to vote their shares of Company common stock, representing approximately 60% of the issued and outstanding shares of Company common stock as of May 24, 2013, the last trading day prior to the public announcement of the execution of the merger agreement, in favor of the proposal to adopt the merger agreement;



•

the fact that Company stockholders who do not vote to adopt the merger agreement and who follow certain prescribed procedures are entitled to appraisal rights under the DGCL; and



•

the opinion of Goldman Sachs delivered to the Company's board of directors that, as of the date of its written opinion, and based upon and subject to the factors and assumptions set forth therein, the merger consideration to be paid to the holders (other than AstraZeneca and its affiliates) of shares of Company common stock pursuant to the merger agreement was fair from a financial point of view to such holders, and the financial analyses related thereto prepared by Goldman Sachs and described below in "The Merger—Opinion of Goldman, Sachs & Co."

        The board of directors also specifically considered the following terms of the merger agreement and related documents (not in any relative order of importance):

•

the merger agreement permits the Company to respond to, and engage in discussions with, third parties who make unsolicited written acquisition proposals, and permits the Company to terminate the merger agreement if the board of directors changes its recommendation or to accept a superior proposal prior to the special meeting of stockholders, subject to the terms and conditions in the merger agreement;



•

the voting agreements entered into by the committed stockholders automatically terminate if the merger agreement is validly terminated by the Company in accordance with its terms;



•

the voting agreements entered into by the committed stockholders may be terminated by such committed stockholders if the board of directors changes its recommendation or the merger agreement is amended or modified in a manner that decreases the amount or changes the form of the merger consideration;



•

the termination fee provisions of the merger agreement were determined by the board of directors to be reasonably customary and not likely be a significant deterrent to competing offers that might constitute superior proposals to the merger;



•

the Company's ability to seek specific performance to prevent breaches of the merger agreement and to enforce specifically the terms of the merger agreement;

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•

the limited conditions to the parties' obligations to complete the merger (including the absence of significant required regulatory approvals); nd



•

the customary nature of the representations, warranties and covenants of the Company in the merger agreement.

        In addition to the merger agreement, the board of directors also reviewed, considered and discussed the terms and potential ramifications of the other transaction documents proposed to be executed in connection with the merger agreement, including the voting agreements and the form of the CVR agreement.

        In the course of its deliberations, the board of directors also considered a variety of risks and other potentially negative factors, including the following:

•

the fact that the stockholders of the Company will have no ongoing equity interest in the surviving corporation following the merger, meaning that the stockholders will cease to participate in the Company's future earnings or growth (except to the extent that they receive payments under the CVRs), or to benefit from any increases in the value of Company common stock;



•

the restrictions the merger agreement imposes on soliciting alternative acquisition proposals;



•

the obligation that the Company pay a termination fee under certain circumstances, and the potential effect of such termination fee in deterring other potential acquirors from proposing alternative transactions (for a full description of the reasons the Company would be required to pay a termination fee to Parent, see "The Merger Agreement—Termination Fees and Expenses" beginning on page 72);



•

the fact that the milestones necessary to trigger payments under the CVRs may not be achieved and therefore that no payments would be made pursuant to the CVRs;



•

the fact that the Company has incurred and will continue to incur significant transaction costs and expenses in connection with the proposed transaction, regardless of whether or not the merger is consummated (including in connection with any litigation that has resulted or may result from the announcement or pendency of the merger);



•

the risk that one or more conditions to the parties' obligations to complete the merger will not be satisfied, and the related risk that the merger may not be completed even if the merger agreement is adopted and approved by the Company's stockholders;



•

the risks and costs to the Company if the merger does not close, including the diversion of management and employee attention, potential employee attrition, the potential adverse effect on the trading price of Company common stock and the potential disruptive effect on business and customer relationships;



•

the effect of a public announcement of the transactions on the Company's operations, stock price and employees and its ability to attract and retain key personnel while the merger is pending, as well as the possibility of any suit, action or proceeding in respect of the merger agreement or the transactions contemplated by the merger agreement;



•

the fact that the committed stockholders are obligated to vote their shares of Company common stock, representing approximately 60% of the issued and outstanding shares of Company common stock as of May 24, 2013, the last trading day prior to the public announcement of the execution of the merger agreement, in favor of the transaction unless the board of directors changes its recommendation, the Company terminates the merger agreement or the merger agreement is amended or modified in a manner that decreases the amount or changes the form of the merger consideration (and accordingly, unless the voting agreements are terminated in

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accordance with their terms, the committed stockholders will vote their shares of Company common stock in favor of adopting the merger agreement and the adoption of the merger agreement will be approved);

•

the fact that the operations of the Company will be restricted by interim operating covenants under the merger agreement during the period between signing the merger agreement and the closing of the merger, which could effectively prohibit the Company from undertaking any strategic initiatives or other material transactions to the detriment of the Company and its stockholders;



•

the interests of our directors and executive officers in the merger, including the matters described under the section entitled, "The Merger—Interests of Certain Persons in the Merger" beginning on page 47; and



•

the fact that a cash transaction would be taxable to the Company's stockholders that are U.S. holders for U.S. federal income tax purposes.

        The foregoing discussion of the factors considered by the board of directors is not intended to be exhaustive, but rather includes the principal factors considered by the board of directors. The board of directors collectively reached the conclusion to approve the merger agreement, the merger and the other transactions contemplated by the merger agreement in light of the various factors described above and other factors that the members of the board of directors believed were appropriate. In view of the wide variety of factors considered by the board of directors in connection with its evaluation of the merger and the complexity of these matters, the board of directors did not consider it practical, and did not attempt, to quantify, rank or otherwise assign relative weights to the specific factors it considered in reaching its decision and did not undertake to make any specific determination as to whether any particular factor, or any aspect of any particular factor, was favorable or unfavorable to the ultimate determination of the board of directors. Rather, the board of directors made its recommendation based on the totality of information presented to it and the investigation conducted by it. In considering the factors discussed above, individual directors may have given different weights to different factors.

         THE BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS THAT YOU VOTE "FOR" APPROVAL OF THE PROPOSAL TO ADOPT THE MERGER AGREEMENT.

Opinion of Goldman, Sachs & Co.

        On May 27, 2013, at a meeting of the board of directors, Goldman Sachs rendered to the board of directors an oral opinion, which was confirmed by delivery of a written opinion dated May 27, 2013, to the effect that, as of the date of the written opinion, and based upon and subject to the factors and assumptions set forth therein, the merger consideration of $12.70 in cash and one CVR to be paid to the holders (other than AstraZeneca and its affiliates) of Company common stock pursuant to the merger agreement was fair from a financial point of view to such holders.

         The full text of the written opinion of Goldman Sachs, dated May 27, 2013, which sets forth assumptions made, procedures followed, matters considered and limitations on the review undertaken in connection with the opinion, is attached to this proxy statement as Annex E. The following summary of Goldman Sachs' opinion is qualified in its entirety by reference to the full text of the opinion. Goldman Sachs provided its opinion for the information and assistance of the board of directors in connection with its consideration of the merger. The Goldman Sachs opinion is not a recommendation as to how any holder of Company 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:

•

the merger agreement;



•

the CVR agreement;



•

the Company's registration statement on Form S-1, as amended, including the Company's Prospectus, dated April 11, 2013, relating to the initial public offering of Company common stock;



•

certain publicly available research analyst reports for the Company; and



•

certain internal financial analyses and forecasts for the Company prepared by its management, including management's forecasts and assessments as to the probability and estimated timing of achievement of Milestone #1, Milestone #2 and Milestone #3 (as defined beginning on page 76), as approved for Goldman Sachs' use by the Company (which we refer to as the Forecasts). For a more detailed description of the Forecasts, see the section entitled "The Merger—Certain Unaudited Prospective Financial and Other Information Concerning the Company" beginning on page 44.

        Goldman Sachs also held discussions with members of the senior management of the Company regarding their assessment of the past and current business operations, financial condition and future prospects of the Company; reviewed the reported price and trading activity for shares of Company common stock; compared certain financial and stock market information for the Company 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 biopharmaceutical 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 Company's consent, 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. In that regard, Goldman Sachs assumed with the Company's consent that the Forecasts have been reasonably prepared on a basis reflecting the best currently available estimates and judgments of the management of the Company. Goldman Sachs did not make any independent evaluation or appraisal of the assets and liabilities (including any contingent, derivative or other off-balance-sheet assets and liabilities) of the Company and was not furnished with any such evaluation or appraisal. 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 the Company or on the expected benefits of the merger in any way meaningful to Goldman Sachs' analysis. Goldman Sachs assumed that the merger will be consummated on the terms set forth in the 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.

        Goldman Sachs' opinion did not address the underlying business decision of the Company to engage in the transactions contemplated by the merger agreement, or the relative merits of the merger as compared to any strategic alternatives that may be available to the Company, nor did 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 (other than AstraZeneca and its affiliates) of shares of Company common stock, as of the date of the written opinion, of the merger consideration of $12.70 in cash and one CVR to be paid to such holders pursuant to the merger agreement. Goldman Sachs did not express any view on, and its opinion did not address, any other term or aspect of the merger agreement or the merger or any term or aspect of any other agreement or instrument contemplated by the merger agreement or entered into or amended in connection with the merger, including the CVR agreement,

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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 the Company, or the fairness of the amount or nature of any compensation to be paid or payable to any of the officers, directors or employees of the Company, or class of such persons, in connection with the merger, whether relative to the consideration to be paid to the holders (other than AstraZeneca and its affiliates) of shares of Company common stock pursuant to the merger agreement or otherwise. Goldman Sachs did not express any opinion as to the impact of the merger on the solvency or viability of the Company, AstraZeneca or Parent or the ability of the Company, AstraZeneca or Parent 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 Goldman Sachs as of, the date of its written 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 written opinion. Goldman Sachs' advisory services and the opinion expressed in its opinion were provided for the information and assistance of the board of directors in connection with its consideration of the merger and such opinion does not constitute a recommendation as to how any holder of shares of Company common stock should vote with respect to such merger or any other matter. Goldman Sachs' opinion was approved by a fairness committee of Goldman Sachs.

Summary of Material Financial Analyses

        The following is a summary of the material financial analyses delivered by Goldman Sachs to the board of directors 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 May 24, 2013, the last trading day before the delivery by Goldman Sachs of its written opinion described above, and is not necessarily indicative of current market conditions.

        Illustrative Analysis at Various Prices.     Goldman Sachs analyzed the implied equity premium per share of Company common stock represented by each of (1) the $12.70 per share in cash, without considering any potential payment under the terms of the CVR agreement, (2) an estimated value of the merger consideration determined by adding $12.70 and the estimated probability-adjusted present value of the potential CVR payments calculated by Goldman Sachs based on the Company management's estimates of the probability and timing of achievement of Milestone #1, Milestone #2 and Milestone #3 (as defined beginning on page 76) as reflected in the Forecasts and (3) the nominal undiscounted value of the merger consideration determined by adding $12.70 and the maximum amounts of the potential CVR payments (each of which we refer to as an Illustrative Price Per Share), in each case as compared to:

•

the $6.77 closing price per share of Company common stock on May 24, 2013,



•

the $8.00 offering price per share of Company common stock in the Company's initial public offering, and



•

the average trading price of $7.15 for the shares of Company common stock over the period from (but not including) April 11, 2013, the date of the Company's initial public offering, through (and including) May 24, 2013.

        Goldman Sachs also calculated the enterprise value associated with each Illustrative Per Share Price by multiplying the applicable Illustrative Price Per Share by the number of outstanding shares of

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Company common stock on a diluted basis and subtracting the amount of the Company's cash balance on April 30, 2013 (as provided by the Company's management), where applicable.

        The results of this analysis are summarized as follows:

        Summary Discounted Cash Flow Analysis.     Goldman Sachs performed an illustrative discounted cash flow analysis on the Company on a standalone basis using estimated unlevered free cash flows for the Company reflected in the Forecasts to calculate an implied equity value per share of the Company. For purposes of its analysis, at the instruction of the Company's management, Goldman Sachs assumed that the Company would effect an incremental $100 million equity financing (net of $5 million of financing fees) at a price of $6.00 per share. Using discount rates ranging from 12.8% to 14.0% (reflecting estimates of the Company's weighted average cost of capital, which were derived by application of the Capital Asset Pricing Model), Goldman Sachs calculated a range of implied enterprise values for the Company by discounting to present value as of April 30, 2013 estimated unlevered free cash flows for the Company for the period from May 2013 through end of the 2025, the net proceeds of the assumed $100 million equity financing in 2014 and a terminal value of the estimated unlevered free cash flows of the Company for the periods after 2025 (calculated by applying perpetuity growth rates ranging from negative 10.0% to negative 20.0% to the Company management's estimate of terminal year unlevered free cash flows). The range of perpetuity growth rates was estimated by Goldman Sachs utilizing its professional judgment and experience, taking into account Company management's guidance regarding the anticipated decline in Company revenues after the expiration of certain patents related to Epanova™. For purposes of its analysis, Goldman Sachs added to the range of the implied enterprise values it calculated the Company's cash balance as of April 30, 2013 to derive a range of implied equity values for the Company. Goldman Sachs divided this range of implied equity values by the Company's diluted outstanding shares calculated using the treasury stock method, as provided by the Company's management and as impacted by the assumed incremental $100 million equity financing to derive implied equity values per share of the Company ranging from $9.56 to $11.48. In the illustrative discounted cash flow analysis described in this paragraph, unlevered free cash flow, which is the Company's projected operating income, minus taxes (calculated by multiplying a tax rate based on Company management's guidance) by the Company's projected operating income, plus depreciation, minus its projected capital expenditures and minus or plus an increase or decrease, respectively, in its net working capital, was calculated using the Forecasts.

        Selected Transaction Analysis.     Goldman Sachs analyzed certain information relating to the following selected transactions, which comprised public acquisition transactions in the biopharmaceutical industry announced since June 7, 2006 with transaction values of between $300 million and $1 billion.

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        For each of the selected transactions, Goldman Sachs calculated and compared the premium represented by the price per share paid for the target to (i) the undisturbed price per share of the target, (ii) the average closing price per share of the target during four weeks prior to the announcement date and (iii) the closing price per share of the target four weeks prior to the announcement date. While none of the companies that participated in the selected transactions are directly comparable to the Company, the companies that participated in the selected transactions are companies with operations that, for the purposes of analysis, may be considered similar to certain of the Company's results, market size and product profile. The following table presents the results of this analysis:

        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 analysis 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 used in the above analyses as a comparison is directly comparable to the Company or the merger.

        Goldman Sachs prepared these analyses for purposes of Goldman Sachs' providing its written opinion to the board of directors as to the fairness from a financial point of view of the consideration

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per share of Company common stock to be paid to the holders (other than AstraZeneca and its affiliates) of shares of Company common stock pursuant to the 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 the Company, Parent, AstraZeneca, Goldman Sachs or any other person assumes responsibility if future results are materially different from those forecast.

        The type and amount of consideration was determined through arms'-length negotiations between the Company and Parent and was approved by the board of directors. Goldman Sachs provided advice to the Company during these negotiations. Goldman Sachs did not, however, recommend any specific consideration to the Company or the board of directors or that any specific consideration constituted the only appropriate consideration for the merger.

        As described above, Goldman Sachs' opinion to the board of directors was one of many factors taken into consideration by the board of directors in making its determination to approve the 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 E .

        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 in which they invest 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 the Company, AstraZeneca, any of their respective affiliates and third parties, including Sofinnova Partners SAS and New Enterprise Associates, Inc., affiliates of which are significant stockholders of the Company, and their respective affiliates and portfolio companies, or any currency or commodity that may be involved in the merger for the accounts of Goldman Sachs and its affiliates and employees and their customers. Goldman Sachs acted as financial advisor to the Company in connection with, and participated in certain of the negotiations leading to, the merger. During the two-year period ended May 27, 2013, Goldman Sachs has not been engaged by the Company or its affiliates to provide services for which the Investment Banking Division of Goldman Sachs has received compensation. Goldman Sachs has provided certain investment banking and other financial services to AstraZeneca and 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 AstraZeneca's corporate broker since September 2005 and as joint book-running manager with respect to the public offering of 1.95% Notes due September 2019 (aggregate principal amount $1,000,000,000) and 4.00% Notes due September 2042 (aggregate principal amount $1,000,000,000) issued by AstraZeneca in September 2012. During the two-year period ended May 27, 2013, the Investment Banking Division of Goldman Sachs has received compensation for services provided to AstraZeneca and its affiliates of approximately $4,431,000. Goldman Sachs may also in the future provide investment banking and other financial services to the Company, AstraZeneca and their respective affiliates, and to Sofinnova Partners SAS and New Enterprise Associates, Inc. and their respective affiliates and portfolio companies, for which the investment banking division of Goldman Sachs may receive compensation. Affiliates of Goldman Sachs also may have co-invested with Sofinnova Partners SAS or New Enterprise Associates, Inc. or their respective affiliates from time to time and may have invested in limited partnership units of affiliates of Sofinnova Partners SAS or New Enterprise Associates, Inc. from time to time and may do so in the future.

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        The board of directors selected Goldman Sachs as its financial advisor because Goldman Sachs is an internationally recognized investment banking firm that has substantial experience in transactions similar to the merger. Pursuant to a letter agreement dated May 21, 2013, the Company engaged Goldman Sachs to act as its financial advisor in connection with the merger. Pursuant to the terms of this engagement letter, the Company has agreed to pay Goldman Sachs a transaction fee of 0.80% of the aggregate consideration to be paid in the merger (but not less than $3.2 million), all of which is contingent upon consummation of the merger. In addition, the Company has agreed to reimburse Goldman Sachs for its expenses, including attorneys' fees and disbursements, and to indemnify Goldman Sachs and related persons against various liabilities, including certain liabilities under the federal securities laws.