Yann Mazabraud - 01 Feb 2026 Form 4 Insider Report for RHYTHM PHARMACEUTICALS, INC. (RYTM)

Role: EVP, Head of International
Signature: /s/ Stephen Vander Stoep, attorney-in-fact for Yann Mazabraud
Issuer symbol: RYTM
Transactions as of: 01 Feb 2026
Net transactions value: $0
Form type: 4
Filing time: 03 Feb 2026, 16:38:11 UTC
Previous filing: 01 May 2025
Next filing: 13 Feb 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Mazabraud Yann	EVP, Head of International	222 BERKELEY STREET, 12TH FLOOR, BOSTON	/s/ Stephen Vander Stoep, attorney-in-fact for Yann Mazabraud	03 Feb 2026	0001774702

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	RYTM	Common Stock	Options Exercise		+5,500	+15%		43,155	01 Feb 2026	Direct	F1

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	RYTM	Restricted Stock Units	Options Exercise	$0	-5,500	-33%	$0.000000	11,000	01 Feb 2026	Common Stock	5,500		Direct	F1, F2

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	Each restricted stock unit represents a contingent right to receive one share of Issuer common stock.
F2	The restricted stock units vest as to 25% of the total shares on each of February 16, 2025, February 1, 2026, February 1, 2027 and February 1, 2028. The restricted stock units have no expiration date.