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): September 30, 2020

Verastem, Inc.

(Exact Name of Registrant as Specified in Charter)

Registrant’s telephone number, including area code: (781) 292-4200

(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:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ¨

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Item 2.01. Completion of Acquisition or Disposition of Assets.

On September 30, 2020, Verastem, Inc. (the “Company”) completed the previously disclosed disposition of the Company’s rights, title and interest in and to COPIKTRA (duvelisib) (“COPIKTRA”), including certain related assets, in all oncology indications, to Secura Bio, Inc. (“Secura Bio”) pursuant to an Asset Purchase Agreement (the “Asset Purchase Agreement”), dated August 10, 2020, between the Company and Secura Bio (the “Transaction”). The purchase price consisted of (i) an up-front payment of $70.0 million in cash, which was paid at the closing of the Transaction (the “Closing”) and (ii) certain additional payments, payable after the Closing and which include (a) regulatory milestone payments of up to $45.0 million, consisting of a payment of $35.0 million upon receipt of regulatory approval of COPIKTRA in the United States for the treatment of peripheral T-cell lymphoma and a payment of $10.0 million upon receipt of regulatory approval of COPIKTRA in the European Union for the treatment of peripheral T-cell lymphoma, (b) sales milestone payments of up to $50.0 million, consisting of $10.0 million when total worldwide net sales of COPIKTRA exceed $100.0 million, $15.0 million when total worldwide net sales of COPIKTRA exceed $200.0 million and $25.0 million when total worldwide net sales of COPIKTRA exceed $300.0 million, (c) low double-digit royalties on the annual aggregate net sales above $100.0 million in the United States and Europe and (d) 50% of all royalty, milestone and sublicense revenue payments payable to Secura Bio under the Company’s existing license agreements with Sanofi, Yakult Honsha Co., Ltd. and CSPC Pharmaceutical Group Limited and 50% of all royalty and milestone payments payable to Secura Bio under future license or sublicense agreement entered into by Secura Bio in certain jurisdictions.

The foregoing description of the Asset Purchase Agreement does not purport to be complete and is qualified in its entirety by reference to the Asset Purchase Agreement, which will be filed as an exhibit to a future filing by the Company with the Securities and Exchange Commission pursuant to the Securities Exchange Act or 1934, as amended.

Item 7.01. Other Events.

On September 30, 2020, the Company issued a press release announcing the completion of the Transaction. A copy of the press release is furnished hereto as Exhibit 99.1.

Item 9.01. Financial Statements and Exhibits.

SIGNATURE

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.