Alastair Garfield - 13 Aug 2026 Form 4 Insider Report for RHYTHM PHARMACEUTICALS, INC. (RYTM)

Reporting relationship: Chief Scientific Officer
Issuer ticker: RYTM
Reported as of: 13 Aug 2026
Net transaction value: -$912,703
SEC form: 4
Accepted by SEC: 17 Aug 2026, 17:57:29 UTC
Prior SEC filing: 02 Jul 2026
Source filing: View source filing
Reporting owner signature: /s/ Stephen Vander Stoep, attorney-in-fact for Alastair Garfield

Key filing fact

Alastair Garfield filed Form 4 for RHYTHM PHARMACEUTICALS, INC. (RYTM) on 17 Aug 2026.

Key facts

This page summarizes Alastair Garfield's Form 4 filing for RHYTHM PHARMACEUTICALS, INC. (RYTM).
4 reported transactions and 0 derivative rows are listed below.
Accepted by SEC: 17 Aug 2026, 17:57.

Change

Previous filing in this sequence was filed on 02 Jul 2026.
Current net transaction value: -$912,703.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0002027261 Primary reporting owner

Garfield Alastair

Relationship: Chief Scientific Officer
Address: C/O RHYTHM PHARMACEUTICALS, INC., 222 BERKELEY STREET, 12TH FLOOR, BOSTON
Signature: /s/ Stephen Vander Stoep, attorney-in-fact for Alastair Garfield
Signature date: 17 Aug 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

RYTM transaction

Common Stock

Sale

Transaction value: $233,031
Shares: -2,007
Change %: -20%
Price: $116.11
Shares after: 8,051
Date: 13 Aug 2026
Ownership: Direct
Footnotes: F1, F2

RYTM transaction

Common Stock

Sale

Transaction value: $182,170
Shares: -1,556
Change %: -19%
Price: $117.08
Shares after: 6,495
Date: 13 Aug 2026
Ownership: Direct
Footnotes: F1, F3

RYTM transaction

Common Stock

Sale

Transaction value: $402,167
Shares: -3,400
Change %: -52%
Price: $118.28
Shares after: 3,095
Date: 13 Aug 2026
Ownership: Direct
Footnotes: F1, F4

RYTM transaction

Common Stock

Sale

Transaction value: $95,335
Shares: -800
Change %: -26%
Price: $119.17
Shares after: 2,295
Date: 13 Aug 2026
Ownership: Direct
Footnotes: F1, F5

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Rule 10b5-1 trading plan

These transactions were reported as open-market trades under a Rule 10b5-1 plan. The plan lets an insider set trading instructions in advance, which can reduce the risk of trading while in possession of material nonpublic information.

Original filing language: transaction made pursuant to a contract, instruction, or written plan intended to satisfy Rule 10b5-1(c).

Explanation of responses 5 footnotes

Footnote F1

The sales reported in the Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 14, 2026.

Footnote F2

The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $115.67 to $116.62 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Footnote F3

The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $116.72 to $117.66 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Footnote F4

The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $117.73 to $118.71 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Footnote F5

The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $118.73 to $119.52 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.