UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):  November 25, 2013

SYNTA PHARMACEUTICALS CORP.

(Exact name of registrant as specified in its charter)

45 Hartwell Avenue

Lexington, MA  02421

(Address of principal executive offices and zip code)

Registrant’s telephone number, including area code: (781) 274-8200

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o      Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o      Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o      Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o      Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

ITEM 1.01 Entry into a Material Definitive Agreement.

On November 25, 2013, Synta Pharmaceuticals Corp. (the “Company”) and its wholly owned subsidiary, Synta Securities Corp., as guarantor, entered into a Ninth Amendment, effective September 30, 2013 (the “Amendment”), to the Company’s Loan and Security Agreement with General Electric Capital Corporation (“GECC”), in its capacity as agent for GECC and MidCap Funding III, LLC as lenders, dated September 30, 2010, as amended on November 9, 2010, March 3, 2011, July 1, 2011, January 23, 2012, July 30, 2012, December 6, 2012, December 14, 2012 and April 1, 2013 (the “GECC Term Loan”). The GECC Term Loan is secured by substantially all of the Company’s assets, except its intellectual property. The GECC Term Loan also provides for a springing security interest in favor of GECC, as agent for the lenders, in the Company’s intellectual property, which would be triggered in the event that the Company is not in compliance with certain cash usage covenants, as defined in the GECC Term Loan. The Amendment provides that the springing security interest in the Company’s intellectual property may not be triggered until after November 29, 2013.

ITEM 9.01           Financial Statements and Exhibits.

(d)           Exhibits.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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EXHIBIT INDEX

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