FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person * COLLIER EARL M JR   2. Issuer Name and Ticker or Trading Symbol TESARO, Inc. [TSRO] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) C/O TESARO, INC., 1000 WINTER STREET 3. Date of Earliest Transaction (Month/Day/Year) 01/22/2019 (Street) WALTHAM,, MA 02451 4. If Amendment, Date Original Filed(Month/Day/Year) 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 01/22/2019   U   2,090 (1) D $ 75 0 D

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Underlying Securities (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Director Restricted Stock Units	(2)	01/22/2019		D			4,052	(3)	(3)	Common Stock	4,052	(3)	0	D
Director Nonqualified Stock Option (right to buy)	$ 26.36	01/22/2019		D			25,000	(4)(5)	06/01/2024	Common Stock	25,000	(4) (5)	0	D
Director Nonqualified Stock Option (right to buy)	$ 60.77	01/22/2019		D			10,000	(4)(5)	06/01/2025	Common Stock	10,000	(4) (5)	0	D
Director Nonqualified Stock Option (right to buy)	$ 47.27	01/22/2019		D			12,000	(4)(5)	06/01/2026	Common Stock	12,000	(4) (5)	0	D
Director Nonqualified Stock Option (right to buy)	$ 149.22	01/22/2019		D			12,000	(4)(5)	06/01/2027	Common Stock	12,000	(4) (5)	0	D
Director Nonqualified Stock Option (right to buy)	$ 46.89	01/22/2019		D			7,209	(4)(5)	06/01/2028	Common Stock	7,209	(4) (5)	0	D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
COLLIER EARL M JR C/O TESARO, INC., 1000 WINTER STREET WALTHAM,, MA 02451	X

Signatures

/s/ Joseph L. Farmer, Attorney-in-Fact		01/22/2019
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Tendered in connection with the tender offer made by Adriatic Acquisition Corporation, a Delaware corporation ("Purchaser") and a wholly-owned subsidiary of GlaxoSmithKline plc, a public company organized under the laws of England and Wales ("Parent"), to purchase all of the issued and outstanding shares of TESARO, Inc., a Delaware corporation ("TESARO"), for $75.00 per share, pursuant to the terms of that certain Agreement and Plan of Merger, dated as of December 3, 2018 by and among TESARO, Purchaser, and Parent (the "Merger Agreement").
(2)	Each restricted stock unit represents a contingent right to receive one share of TESARO common stock.
(3)	These restricted stock units were cancelled pursuant to the Merger Agreement at the effective time of the Merger (the "Effective Time") in exchange for a cash payment of $75.00 per share.
(4)	Pursuant to the Merger Agreement, each option that was outstanding and unvested immediately prior to the Effective Time vested in full at the Effective Time. [Cont'd]
(5)	[Continuation] Each option that was outstanding immediately prior to the Effective Time that had an exercise price per share less than $75.00 was cancelled in exchange for the right of the holder to receive (without interest) an amount in cash (less applicable withholding of taxes required by applicable law) equal to the product of (i) the total number of shares of TESARO common stock subject to the unexercised portion of such option immediately prior to the Effective Time (determined after giving effect to the accelerated vesting described in the previous sentence) multiplied by (ii) the excess, if any, of $75.00 over the applicable exercise price per share under such option. Each option that was outstanding immediately prior to the Effective Time with an exercise price per share that is greater than or equal to $75.00 was cancelled at the Effective Time, and the holder of such option is not entitled to any payment in exchange for the cancellation of the option.

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