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): May 16, 2018

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 (see General Instruction A.2. below):

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))

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 o

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. o

Item 8.01. Other Events.

On May 16, 2018, Verastem, Inc. (the “Company”) entered into an Underwriting Agreement (the “Underwriting Agreement”) with Cantor Fitzgerald & Co. (“Cantor”) relating to the underwritten offering of 7,777,778 shares (the “Shares”) of the Company’s common stock, par value $0.0001 per share (the “Offering”).  Cantor has agreed to purchase the Shares pursuant to the Underwriting Agreement at a price of $4.31 per share. In addition, the Company granted Cantor an option to purchase, at the public offering price less any underwriting discounts and commissions, an additional 1,166,666 shares of Common Stock, exercisable for 30 days from the date of the prospectus supplement.

The Offering is being made pursuant to a shelf registration statement the Company filed with the Securities and Exchange Commission that became effective on April 24, 2017 (Registration No. 333-217048) (the “Registration Statement”) and a related prospectus supplement. The closing of the Offering is expected to take place on or about May 18, 2018, subject to the satisfaction of customary closing conditions.

A copy of the Underwriting Agreement is filed as Exhibit 1.1 to this Current Report on Form 8-K.

Ropes & Gray LLP, counsel to the Company, has issued an opinion to the Company, dated May 18, 2018 regarding the Shares to be sold in the Offering. A copy of the opinion is filed as Exhibit 5.1 to this Current Report on Form 8-K.

Item 9.01. Financial Statements and Exhibits.

See Exhibit Index attached hereto.

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EXHIBIT INDEX

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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.

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