SNTA Synta Pharmaceuticals Corp. (MM)

NOTICE OF 2016 ANNUAL MEETING OF SYNTA STOCKHOLDERS
TO BE HELD ON JULY 21, 2016

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         Even if you plan to attend the Annual Meeting in person, Synta requests that you please sign and return the enclosed proxy to ensure that your shares will be represented at the Annual Meeting if you are unable to attend. You may change or revoke your proxy at any time before it is voted at the meeting.

         THE SYNTA BOARD OF DIRECTORS HAS DETERMINED AND BELIEVES THAT EACH OF THE PROPOSALS OUTLINED ABOVE IS ADVISABLE TO, AND IN THE BEST INTERESTS OF, SYNTA AND ITS STOCKHOLDERS AND HAS APPROVED EACH PROPOSAL. THE SYNTA BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS THAT SYNTA STOCKHOLDERS VOTE "FOR" EACH PROPOSAL.

		By Order of the Synta Board of Directors,
		Wendy E. Rieder, Esq. Senior Vice President, General Counsel and Secretary Lexington, Massachusetts June 8, 2016

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SYNTA PHARMACEUTICALS CORP.
PROXY STATEMENT FOR 2016 ANNUAL MEETING OF STOCKHOLDERS

ABOUT THIS DOCUMENT

        Synta Pharmaceuticals Corp., which we refer to herein as the "Company," "Synta," "we," "our," or "us," is providing these proxy materials in connection with the solicitation by our board of directors of proxies to be voted at our annual meeting of stockholders to be held at 9:00 am, local time, on July 21, 2016, at the offices of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., One Financial Center, Boston, MA 02111, or at any adjournment or postponement thereof, or Annual Meeting. This proxy statement and the enclosed proxy card will be mailed to each stockholder entitled to notice of, and to vote at, the Annual Meeting commencing on or about June 13, 2016.

        You should rely only on the information contained in or incorporated by reference into this proxy statement. No one has been authorized to provide you with information that is different from that contained in or incorporated by reference into this proxy statement. This proxy statement is dated June 8, 2016. You should not assume that the information contained in this proxy statement is accurate as of any other date, nor should you assume that the information incorporated by reference into this proxy statement is accurate as of any date other than the date of such incorporated document. The mailing of this proxy statement to our stockholders will not create any implication to the contrary.

        Except where specifically noted, the following information and all other information contained in this proxy statement does not give effect to the proposed reverse stock split described in Proposal No. 2, beginning on page 156 in this proxy statement.

         This proxy statement does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the solicitation of a proxy, in any jurisdiction in which or from any person to whom it is unlawful to make any such offer or solicitation in such jurisdiction.

REFERENCES TO ADDITIONAL INFORMATION

        This proxy statement incorporates important business and financial information about Synta that is not included in or delivered with this document. You may obtain this information without charge through the Securities and Exchange Commission (the "SEC") website (www.sec.gov) or upon your written or oral request by contacting the Wendy E. Rieder, Senior Vice President, General Counsel of Synta Pharmaceuticals Corp., 125 Hartwell Avenue, Lexington, MA 02421 or by calling (781) 274-8200.

        You may also request information from The Proxy Advisory Group, LLC, Synta's proxy solicitor, at the following address and telephone number:

The Proxy Advisory Group, LLC
Shareholders Call Toll Free: (888) 337-7699, or 888-33PROXY

        For additional details about where you can find information about Synta, please see the section entitled "Where You Can Find More Information" in this proxy statement.

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QUESTIONS AND ANSWERS ABOUT THE MERGER

        Except where specifically noted, the following information and all other information contained in this proxy statement does not give effect to the proposed reverse stock split described in Proposal No. 2, beginning on page 156 of this proxy statement.

        The following section provides answers to frequently asked questions about the merger. This section, however, provides only summary information. Please refer to the more detailed information contained elsewhere in this proxy statement and the annexes to and the documents referred to or incorporated by references in this proxy statement.

Q.

Why am I receiving this proxy statement?

A:

You are receiving this proxy statement because you have been identified as a stockholder of Synta as of the record date for the 2016 annual meeting of stockholders, or the Annual Meeting. You are being asked to vote at the Annual Meeting to approve, among other things, the issuance of shares of Synta common stock as contemplated by the Merger Agreement. This document serves as a proxy statement of Synta used to solicit proxies for the Annual Meeting.

Q:

What is the merger?

A:

Synta and Madrigal Pharmaceuticals, Inc., or Madrigal, have entered into an Agreement and Plan of Merger and Reorganization, dated as of April 13, 2016, which we refer to as the Merger Agreement. The Merger Agreement contains the terms and conditions of the proposed business combination of Synta and Madrigal. Under the Merger Agreement, Saffron Merger Sub, Inc., a wholly-owned subsidiary of Synta, or Saffron Merger Sub, will merge with and into Madrigal, with Madrigal surviving as a wholly-owned subsidiary of Synta. Thereafter, Synta will change its corporate name to "Madrigal Pharmaceuticals, Inc." as required by the Merger Agreement. This transaction is referred to as "the merger."

At the effective time of the merger, each share of Madrigal common stock outstanding immediately prior to the effective time of the merger will be converted into the right to receive 5.5740 shares of Synta common stock, subject to adjustment to account for the proposed reverse stock split to be implemented prior to the closing of the merger.

As a result, immediately following the completion of the merger, Madrigal's current securityholders would own in the aggregate approximately 64% of the combined company's outstanding common stock (with Bay City Capital, LLC, or Bay City Capital, and its affiliates, Madrigal's largest securityholder, owning approximately 52.5% of the combined company's outstanding shares of common stock) and Synta's current holders of common stock and restricted stock units (together referred to as Synta's equityholders) would own in the aggregate approximately 36% of the combined company's outstanding common stock. This calculation does not contemplate outstanding Synta option awards, which will remain outstanding under their existing terms following the merger, nor does it include equity awards in the amount of 20,825,936 shares of common stock of the combined company that are expected to be granted immediately after the completion of the merger to Paul A. Friedman, M.D., and Rebecca Taub, M.D., as executive officers of the combined company.

For a more complete description of what Madrigal stockholders will receive in the merger, please see the section entitled "The Merger Agreement—Merger Consideration" beginning on page 99.

Q:

What will happen to Synta if, for any reason, the merger does not close?

A:

If, for any reason, the merger does not close, the Synta board of directors may elect to, among other things, attempt to complete another strategic transaction like the merger, attempt to sell or

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otherwise dispose of the various assets of Synta or continue to operate the business of Synta. If Synta decides to dissolve and liquidate its assets, Synta would be required to pay all of its debts and contractual obligations and to set aside certain reserves for potential future claims, and there can be no assurances as to the amount or timing of available cash left to distribute to stockholders after paying the debts and other obligations of Synta and setting aside funds for reserves in the event of such a liquidation.

If Synta were to continue its business, it would need to re-evaluate its strategic direction relating to STA-12-8666, including potentially submitting an Investigational New Drug Application, or IND, for STA-12-8666, and may need to identify, acquire and develop other products or product candidates. In addition, as of June 1, 2016, the Synta workforce was comprised of nine employees, most of whom are involved in general and administrative roles. Synta has only one employee currently engaged in development and regulatory activities. If Synta decides to re-evaluate its current business alternatives, Synta may need to hire managerial and other personnel to lead and staff a variety of necessary functions, including in particular research, development and commercialization.

Q:

Why are the two companies proposing to merge?

A:

Madrigal and Synta believe that the merger will result in a financially strong pharmaceutical company focused on the development of novel small-molecule drugs addressing major unmet needs in cardiovascular, metabolic and liver diseases. Madrigal and Synta expect that the combined company will have the resources to fund the development of MGL-3196, a Phase 2-ready, once-daily, oral, liver-directed, selective thyroid hormone receptor-ß, or THR-ß, agonist for the treatment of non-alcoholic steatohepatitis, or NASH, heterozygous familial hypercholesterolemia, or HeFH, and homozygous familial hypercholesterolemia, or HoFH, through Phase 2 clinical studies in NASH, HeFH and HoFH. For a discussion of Synta's reasons for the merger, please see the sections entitled "The Merger—Background of the Merger" beginning on page 67 and "The Merger—Reasons for the Merger" beginning on page 76.

Q:

How much cash will Synta have at the closing of the merger?

A:

It is a closing condition of the Merger Agreement that Synta have net cash of at least $28.5 million at the closing of the merger. The actual amount of net cash will depend mostly on the timing of the closing.

Q:

What is required to complete the merger?

A:

To complete the merger, Synta stockholders must approve the issuance of Synta common stock to Madrigal securityholders by virtue of the merger as contemplated by the Merger Agreement and the amendment to the restated certificate of incorporation of Synta effecting the reverse stock split.

The approval of the Merger Agreement, the merger and the issuance of shares of Synta common stock requires the affirmative vote of a majority of the votes cast on this proposal at the Annual Meeting. The approval of the reverse stock split requires the affirmative vote of the holders of a majority of the outstanding shares of Synta common stock entitled to vote on the record date for the Annual Meeting. The approval of the reverse stock split is required in order to authorize Synta's issuance of the shares of its common stock pursuant to the Merger Agreement and to maintain the listing of Synta common stock on The NASDAQ Global Market or The NASDAQ Capital Market. However, if the requisite number of stockholders of Synta approve the Merger Agreement, the merger and the issuance of shares of Synta common stock but do not approve the reverse stock split, the merger will not be completed.

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In addition to the requirement of obtaining such stockholder approvals, each of the other closing conditions set forth in the Merger Agreement must be satisfied or waived.

Also, certain Synta stockholders who, in the aggregate, own approximately 18.2% of the outstanding shares of Synta common stock, are parties to voting agreements with Synta and Madrigal whereby the stockholders agreed to vote in favor of the issuance of Synta common stock in the merger as contemplated by the Merger Agreement.

For a more complete description of the closing conditions under the Merger Agreement, you are urged to read the section entitled "The Merger Agreement—Conditions to Completion of the Merger" beginning on page 110 of this proxy statement.

Q:

Are there any federal or state regulatory requirements that must be complied with or federal or state regulatory approvals or clearances that must be obtained in connection with the merger?

A:

Neither Synta nor Madrigal is required to make any filings or obtain any approvals or clearances from any antitrust regulatory authorities in the United States or other countries to consummate the merger. In the United States, Synta must comply with applicable federal and state securities laws and The NASDAQ Stock Market's rules and regulations in connection with the issuance of the shares in connection with the merger, including the filing with the SEC, of this proxy statement. Synta has filed an initial listing application with The NASDAQ Global Market or The NASDAQ Capital Market pursuant to The NASDAQ Stock Market's "change of control" rules. If such application is accepted, Synta anticipates that Synta's common stock will be listed on The NASDAQ Global Market or The NASDAQ Capital Market following the closing of the merger under the trading symbol "MDGL."

Q:

Will holders of the Synta common shares issued in the merger be able to trade those shares?

A:

The shares of Synta common stock issued as consideration in the merger will be issued in transactions exempt from registration under the Securities Act of 1933 as amended, or the Securities Act, in reliance on Section 4(a)(2) of the Securities Act, and Regulation D promulgated thereunder and may not be offered or sold by the holders of those shares absent registration or an applicable exemption from registration requirements. As a general matter, holders of such shares will not be able to transfer any of their shares until at least six months after receiving shares of Synta common stock, which is when the shares would first be eligible to be sold under Rule 144 promulgated under the Securities Act, assuming the conditions thereof are otherwise satisfied. In connection with the merger, however, Synta has agreed to file with the SEC a registration statement on Form S-3 to register the shares of Synta common stock received in the merger for resale in the public markets. Upon such registration statement being declared effective by the SEC, such shares shall become freely tradeable subject to certain limitations for stockholders deemed to be affiliates of the combined company.

However, all securityholders of Madrigal, and each director and executive officer of Madrigal, have agreed to certain transfer restrictions on all of their Synta shares from April 13, 2016 until 180 days after the closing date of the merger. See the section in this proxy statement entitled "Agreements Related to the Merger—Lock-Up Agreements" for more detail.

Q:

Who will be the directors of Synta following the completion of the merger?

A:

The combined company's board of directors will initially be fixed at seven members, consisting of (i) one member designated by Synta, Keith R. Gollust, the current Chairman of the board of directors of Synta, (ii) one member to be mutually agreed upon by Synta and Madrigal meeting the SEC and NASDAQ independence requirements, and (iii) five members designated by Madrigal, namely Paul A. Friedman, M.D., who will be the Chairman; Rebecca Taub, M.D.;

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Fred Craves, Ph.D., who will be the lead director and who currently is the founder and managing director of Bay City Capital (which together with its affiliates will own approximately 52.5% of the combined company's outstanding shares of common stock immediately following the closing of the merger); Kenneth M. Bate and one additional Madrigal designee who meets the SEC and NASDAQ independence requirements. The staggered structure of the current Synta board of directors will remain in place for the combined company following the completion of the merger, provided that Keith R. Gollust will be re-appointed as a Class III director.

Pursuant to the terms of the Merger Agreement, it is anticipated the director classes of the combined company board of directors will be as follows:

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Class I directors (term ending 2017): Paul A. Friedman, M.D. and Kenneth M. Bate;



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Class II directors (term ending 2018): Rebecca Taub, M.D. and Fred Craves, Ph.D.; and



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Class III directors (term ending 2019): Keith R. Gollust, one mutual designee and one Madrigal designee.

Q:

Who will be the executive officers of Synta immediately following the completion of the merger?

A:

Immediately following the completion of the merger, the executive management team of Synta is expected to be composed of Paul A. Friedman, M.D., serving as the Chief Executive Officer and Chairman of the Board of the combined company, Rebecca Taub, M.D., serving as Chief Medical Officer, Executive Vice President, Research & Development and Director of the combined company, and Marc R. Schneebaum serving as Chief Financial Officer of the combined company.

Q:

Am I entitled to appraisal rights?

A:

Holders of Synta common stock are not entitled to appraisal rights in connection with the merger.

Q:

Have Madrigal's stockholders adopted the Merger Agreement and approved the merger?

A:

Yes. On April 13, 2016, all of Madrigal's stockholders adopted the Merger Agreement and approved the merger and related transactions. Accordingly, no appraisal rights are available to Madrigal stockholders in connection with this transaction.

Q:

What are the material U.S. federal income tax consequences of the merger to Synta stockholders?

A:

Each of Synta and Madrigal intends the merger to qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code of 1986, as amended, or the Code. Since Synta stockholders will continue to own and hold their existing shares of Synta common stock following the merger, the merger generally will not result in U.S. federal income tax consequences to Synta stockholders.

However, tax matters are very complicated and the tax consequences to a particular Synta stockholder will depend on such stockholder's circumstances. Accordingly, you should consult your tax advisor for a full understanding of the tax consequences of the merger and reverse stock split to you, including the applicability and effect of federal, state, local and foreign income and other tax laws.

Q:

Do persons involved in the merger have interests that may conflict with mine as a Synta stockholder?

A:

Yes. When considering the recommendation of the Synta board of directors, you should be aware that certain members of the Synta board of directors and named executive officers of Synta have interests in the merger that may be different from, or in addition to, interests they may have as

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Synta stockholders. The Synta board of directors was aware of the following interests and considered them, among other matters, in its decision to approve the Merger Agreement.

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Continued Service with Combined Company

At the effective time of the merger, the officers of the combined company will include:

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Paul A. Friedman, M.D., a director of Synta from March 2014 until his resignation on April 13, 2016 concurrent with the announcement of the merger with Madrigal, who will be the Chief Executive Officer and Chairman of the combined company;



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Rebecca Taub, M.D., a current executive officer of Madrigal who will be the Chief Medical Officer, Executive Vice President, Research & Development and Director, of the combined company; and



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Marc R. Schneebaum, the current Chief Financial Officer of Synta, who will continue as the Chief Financial Officer of the combined company.

Additionally, Keith R. Gollust, currently a director of Synta, will continue as a director of the combined company after the effective time of the merger.

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Synta Director Paul A. Friedman's Relationship with Madrigal and the Combined Company

Dr. Friedman has personal interests both in Madrigal and the combined company. These interests were fully disclosed to and known by the Synta board of directors and corporate governance measures were taken to address them, including Dr. Friedman's exclusion from Synta board of director proceedings with respect to Madrigal, as described more fully in "The Merger—Background of the Merger." These interests are:

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The current Chief Executive Officer of Madrigal, Rebecca Taub, M.D. and Dr. Friedman are married.



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Upon the closing of the merger, Dr. Friedman and Dr. Taub will be employed as executive officers of the combined company as described above.



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Dr. Friedman and Dr. Taub have irrevocably committed to loan approximately $5 million to Madrigal in the form of promissory notes that will convert into 25,905,930 shares of Synta common stock as part of the merger closing.



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Dr. Friedman and Dr. Taub will have significant beneficial ownership interests in the combined company due in part to the post-closing entity's equity compensation arrangements with Dr. Friedman and Dr. Taub. Assuming the full vesting and exercise of options to purchase 14,875,669 shares of common stock and the vesting 5,950,267 shares of restricted stock, and based on the projected number of shares of Synta common stock to be outstanding immediately after the closing, Dr. Friedman and Dr. Taub would have a pro forma stock ownership of 60,493,023 shares of the combined company, or approximately 14.5% immediately after the closing of the merger.



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Other

Upon a termination of employment in connection with the merger, Synta's named executive officers may receive cash severance payments and other benefits with a total value of approximately $3.2 million (collectively, not individually, and including the value of the accelerated vesting of unvested restricted stock awards and the vesting of restricted stock unit awards).

See "The Merger—Background of the Merger" beginning on page 67 and "The Merger—Interests of the Synta Directors and Executive Officers in the Merger" beginning on page 90.

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Q:

Why is Synta seeking stockholder approval of the merger and the issuance of shares of common stock issuable upon the merger?

A:

Because our common stock is listed on The NASDAQ Capital Market, we are subject to The NASDAQ Stock Market Listing Rules. Rule 5635(a) of The NASDAQ Stock Market listing standards requires stockholder approval with respect to issuances of Synta common stock, among other instances, when the shares to be issued are being issued in connection with the acquisition of the stock of another company and are equal to 20% or more of Synta's outstanding common stock before the issuance. Rule 5635(b) of the The NASDAQ Stock Market listing standards requires stockholder approval when any issuance or potential issuance will result in a change of control of the issuer. Although The NASDAQ Stock Market has not adopted any rule on what constitutes a "change of control" for purposes of Rule 5635(b), The NASDAQ Stock Market has previously indicated that the acquisition of, or right to acquire, by a single investor or affiliated investor group, as little as 20% of the common stock (or securities convertible into or exercisable for common stock) or voting power of an issuer could constitute a change of control.

In addition, Rule 5635(d) of The NASDAQ Stock Market Listing Rules requires stockholder approval if a listed company issues common stock or securities convertible into or exercisable for common stock in a private placement equal to 20% or more of the common stock or 20% or more of the voting power outstanding before the issuance for less than the greater of book or market value of the stock.

Following the closing of the merger, the current Madrigal securityholders are expected to own approximately 64% of the aggregate number of shares of Synta common stock (with Bay City Capital and its affiliates, Madrigal's largest securityholder, owning approximately 52.5% of the combined company's outstanding shares of common stock) and the Synta equityholders as of immediately prior to the effective time of the merger are expected to own approximately 36% of the aggregate number of shares of Synta common stock. This calculation does not contemplate outstanding Synta option awards, which will remain outstanding under their existing terms following the merger, nor does it include equity awards in the amount of 20,825,936 shares of common stock of the combined company that are expected to be granted immediately after the completion of the merger to Paul A. Friedman, M.D. and Rebecca Taub, M.D., as executive officers of the combined company.

Q:

As a Synta stockholder, how does the Synta board of directors recommend that I vote?

A:

After careful consideration, the Synta board of directors unanimously recommends that Synta stockholders vote "FOR" Proposal Nos. 1 through 8. For a detailed description of each of Proposal Nos. 1 through 8, see the section entitled "Matters Being Submitted to a Vote of Synta Stockholders" beginning on page 155.

Q:

What risks should I consider in deciding whether to vote in favor of the merger?

A:

You should carefully review the section of this proxy statement entitled "Risk Factors," beginning on page 26, which sets forth certain risks and uncertainties related to the merger, risks and uncertainties to which the combined company's business will be subject, and risks and uncertainties to which each of Synta and Madrigal, as an independent company, is subject.

Q:

What is "golden parachute" compensation and why I am being asked to vote on it?

A:

The SEC has adopted rules that require Synta to seek an advisory (non-binding) vote on "golden parachute" compensation. "Golden parachute" compensation is compensation that is tied to or based on the merger and that will or may be paid by Synta to its named executive officers in connection with the merger.

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Q:

When do you expect the merger to be completed?

A:

Synta and Madrigal anticipate that the merger will occur soon after the Annual Meeting, which is expected to occur in the third quarter of 2016, but Synta cannot predict the exact timing. For more information, please see the section entitled "The Merger Agreement—Conditions to Completion of the Merger" beginning on page 110.

Q:

What do I need to do now?

A:

You are urged to read this proxy statement carefully, including its annexes, and to consider how the merger affects you.

You may provide your proxy instructions by mailing your signed proxy card in the enclosed return envelope, vote by Internet or telephone, or vote in person at the Annual Meeting. Please provide your proxy instructions only once, unless you are revoking a previously delivered proxy instruction, and as soon as possible so that your shares can be voted at the Annual Meeting.

Q:

What constitutes a quorum at the Annual Meeting?

A:

The presence at the Annual Meeting, in person or by proxy, of the holders of a majority of the shares of Synta common stock issued and outstanding on the record date for the Annual Meeting will constitute a quorum for the transaction of business at the Annual Meeting.

Q:

What happens if I abstain?

A:

Shares abstaining from voting on a matter will be counted for the purpose of determining whether a quorum exists for the Annual Meeting, but are treated as having not voted. Abstentions will have the same effect as voting against Proposal Nos. 1 and 2, but will have no impact on the outcome of the vote for Proposal Nos. 3, 4, 5, 6, 7 and 8.

Q:

If my Synta shares are held in "street name" by my broker, will my broker vote my shares for me?

A:

Unless your broker has discretionary authority to vote on certain matters, your broker will not be able to vote your shares of Synta common stock without instructions from you. Brokers are not expected to have discretionary authority to vote for Proposal Nos. 1, 3, 4, 5, 6 or 8. To make sure that your vote is counted, you should instruct your broker to vote your shares, following the procedures provided by your broker.

Q.

How Do I Vote?

A.

Whether you plan to attend the Annual Meeting or not, we urge you to vote by proxy. All shares represented by valid proxies that we receive through this solicitation, and that are not revoked, will be voted in accordance with your instructions on the proxy card or as instructed via Internet or telephone. You may specify whether your shares should be voted for the nominee for director and whether your shares should be voted for, against or to abstain with respect to each of the other proposals. If you properly submit a proxy without giving specific voting instructions, your shares will be voted in accordance with the board of directors' recommendations as noted below. Voting by proxy will not affect your right to attend the Annual Meeting. If your shares are registered directly in your name through our stock transfer agent, Computershare Trust Company, N.A., or you have stock certificates registered in your name, you may vote:

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By mail.   If you received a proxy card by mail, you can vote by mail by completing, signing, dating and returning the proxy card as instructed on the card. Your proxy will be voted in accordance with your instructions. If you sign the proxy card but do not specify how you want your shares voted, they will be voted as recommended by our board of directors below.

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By Internet or by telephone.   Follow the instructions on the proxy card to vote by Internet or telephone.



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In person at the meeting.   If you attend the meeting, you may deliver your completed proxy card in person or you may vote by completing a ballot, which will be available at the meeting.

Telephone and Internet voting facilities for stockholders of record will be available 24-hours a day and will close at 1:00 a.m., Central Time, on July 21, 2016.

If your shares are held in "street name" (held in the name of a bank, broker or other holder of record), you will receive instructions from the holder of record. You must follow the instructions of the holder of record in order for your shares to be voted. Telephone and Internet voting also will be offered to stockholders owning shares through certain banks and brokers.

Q:

May I vote in person at the Annual Meeting?

A:

If your shares of Synta common stock are registered directly in your name with the Synta transfer agent, you are considered to be the stockholder of record with respect to those shares, and the proxy materials and proxy card are being sent directly to you by Synta. If you are a Synta stockholder of record, you may attend the Annual Meeting and vote your shares in person. Even if you plan to attend the Annual Meeting in person, Synta requests that you sign and return the enclosed proxy to ensure that your shares will be represented at the Annual Meeting if you are unable to attend. If your shares of Synta common stock are held in a brokerage account or by another nominee, you are considered the beneficial owner of shares held in "street name," and the proxy materials are being forwarded to you by your broker or other nominee together with a voting instruction card. As the beneficial owner, you are also invited to attend the Annual Meeting. Because a beneficial owner is not the stockholder of record, you may not vote these shares in person at the Annual Meeting unless you obtain a proxy from the broker, trustee or nominee that holds your shares, giving you the right to vote the shares at the meeting.

Q:

When and where is the Annual Meeting being held?

A:

The Annual Meeting will be held at the offices of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., One Financial Center, Boston, MA 02111, at 9:00 am, local time, on July 21, 2016. Subject to space availability, all Synta stockholders as of the record date, or their duly appointed proxies, may attend the Annual Meeting.

Q:

May I change my vote after I have submitted a proxy or provided proxy instructions?

A:

Synta stockholders of record, other than those Synta stockholders who are parties to voting agreements, may revoke their proxy at any time before their proxy is voted at the Annual Meeting in one of three ways. First, a stockholder of record of Synta can send a written notice to the Secretary of Synta stating that it would like to revoke its proxy. Second, a stockholder of record of Synta can submit new proxy instructions on a new proxy card. Third, a stockholder of record of Synta can attend the Annual Meeting and vote in person. Attendance alone will not revoke a proxy. If a Synta stockholder of record or a stockholder who owns Synta shares in "street name" has instructed a broker to vote its shares of Synta common stock, the stockholder must follow directions received from its broker to change those instructions.

Q:

Who is paying for this proxy solicitation?

A:

Synta will bear its own expenses in printing and filing this proxy statement and the proxy card. Arrangements will also be made with brokerage firms and other custodians, nominees and fiduciaries who are record holders of Synta common stock for the forwarding of solicitation

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materials to the beneficial owners of Synta common stock. Synta will reimburse the brokers, custodians, nominees and fiduciaries for the reasonable out-of-pocket expenses they incur in connection with the forwarding of solicitation materials to beneficial owners of Synta common stock. We have engaged The Proxy Advisory Group, LLC to advise us on certain proposals in this proxy statement. We have engaged The Proxy Advisory Group, LLC to assist in the solicitation of proxies and provide related advice and informational support, for a services fee and the reimbursement of customary disbursements that are not expected to exceed $25,000 in the aggregate.

Q:

Who can help answer my questions?

A:

If you are a Synta stockholder and would like additional copies, without charge, of this proxy statement or if you have questions about the merger, including the procedures for voting your shares, you should contact:

Synta Pharmaceuticals Corp.
125 Hartwell Avenue
Lexington, MA 02421
Tel: (781) 274-8200
Attn: Wendy E. Rieder, Senior Vice President, General Counsel

You may also request information from The Proxy Advisory Group, LLC, Synta's proxy solicitor, at the following address and telephone number:

The Proxy Advisory Group, LLC
Shareholders Call Toll Free: (888) 337-7699, or 888-33PROXY

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