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): October 23, 2017

TESARO, Inc.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code:  (339) 970-0900

(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

Section 5 – Corporate Governance and Management

Item 5.02.  Departure of Directors or Principal Officers; Election of Directors; Appointment of Principal Officers.

On October 23, 2017, Edward C. English submitted his resignation as principal accounting officer of TESARO, Inc. (the “Company”), in order to pursue personal interests after serving with the company since 2012.  Mr. English will continue to serve until the effective date of his resignation on November 24, 2017.  It is expected that Timothy Pearson, the Company’s Executive Vice President and Chief Financial Officer, will serve as the Company’s principal accounting officer until a successor is appointed.  Mr. English’s departure is not due to a dispute or disagreement with the Company or its independent accountants.

Section 7 – Regulation FD

Item 7.01.  Regulation FD Disclosure.

On October 25, 2017, the Company issued a press release announcing that the U.S. Food and Drug Administration has approved the Company’s new drug application for the intravenous formulation of VARUBI® (rolapitant) in combination with other antiemetic agents in adults for the prevention of delayed nausea and vomiting associated with initial and repeat courses of emetogenic cancer chemotherapy, including, but not limited to, highly emetogenic chemotherapy.

A copy of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K.

Section 9 – Financial Statements and Exhibits

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.

Dated:  October 27, 2017

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