Statement of Changes in Beneficial Ownership (4)

FORM 4

[X] 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

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3235-0287

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Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

1. Name and Address of Reporting Person * Brennan Aoife	2. Issuer Name and Ticker or Trading Symbol Ra Pharmaceuticals, Inc. [ RARX ]	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 RA PHARMACEUTICALS, INC., 87 CAMBRIDGEPARK DRIVE	3. Date of Earliest Transaction (MM/DD/YYYY) 4/2/2020
(Street) CAMBRIDGE, MA 02140 (City)        (State)        (Zip)	4. If Amendment, Date Original Filed (MM/DD/YYYY)	6. Individual or Joint/Group Filing (Check Applicable Line) _X _ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security (Instr. 3)	2. Trans. Date	2A. Deemed Execution Date, if any	3. Trans. 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

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	4. Trans. 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		7. Title and Amount of Securities Underlying Derivative Security (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
Stock Option (Right to Buy)	$19.88	4/2/2020		D			15000 (1)	(2)	6/11/2029	Common Stock	15000	$0 (2)	0	D
Stock Option (Right to Buy)	$16.36	4/2/2020		D			25000 (1)	(2)	9/21/2028	Common Stock	25000	$0 (2)	0	D

Explanation of Responses:
(1)	Disposed of pursuant to an Agreement and Plan of Merger (the "Merger Agreement"), dated October 9, 2019, among Ra Pharmaceuticals, Inc. (the "Issuer"), UCB S.A., and Franq Merger Sub, Inc., providing for the merger (the "Merger") of Franq Merger Sub, Inc. into the Issuer, in exchange for a cash payment of $48.00 per share.
(2)	Pursuant to the Merger Agreement, at the effective time of the Merger, each option, whether vested or unvested, was cancelled in exchange for a cash payment equal to: (a) the number of shares of Issuer common stock underlying the option, multiplied by (b) the excess of $48.00 over the per share exercise price of such option.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Brennan Aoife C/O RA PHARMACEUTICALS, INC. 87 CAMBRIDGEPARK DRIVE CAMBRIDGE, MA 02140	X

Signatures
/s/ David C. Lubner, Attorney-in Fact for Aoife M. Brennan		4/3/2020
**Signature of Reporting Person		Date