David P. Meeker - 14 Sep 2026 Form 4 Insider Report for RHYTHM PHARMACEUTICALS, INC. (RYTM)

Reporting relationship: President and CEO, Director
Issuer ticker: RYTM
Reported as of: 14 Sep 2026
Net transaction value: -$5,133,442
SEC form: 4
Accepted by SEC: 14 Sep 2026, 19:37:32 UTC
Prior SEC filing: 18 Jun 2026
Source filing: View source filing
Reporting owner signature: /s/ Stephen Vander Stoep, attorney-in-fact for David P. Meeker

Key filing fact

David P. Meeker filed Form 4 for RHYTHM PHARMACEUTICALS, INC. (RYTM) on 14 Sep 2026.

Key facts

This page summarizes David P. Meeker's Form 4 filing for RHYTHM PHARMACEUTICALS, INC. (RYTM).
7 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 14 Sep 2026, 19:37.

Change

Previous filing in this sequence was filed on 18 Jun 2026.
Current net transaction value: -$5,133,442.

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 0001385155 Primary reporting owner

Meeker David P

Relationship: President and CEO, Director
Address: C/O RHYTHM PHARMACEUTICALS, INC., 222 BERKELEY STREET, 12TH FLOOR, BOSTON
Signature: /s/ Stephen Vander Stoep, attorney-in-fact for David P. Meeker
Signature date: 14 Sep 2026

Reported non-derivative transactions

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

RYTM transaction

Common Stock

Options Exercise

Transaction value
Shares: +50,000
Change %: +21%
Price: $6.05^*
Shares after: 289,258
Date: 14 Sep 2026
Ownership: Direct
Footnotes: F1, F2

RYTM transaction

Common Stock

Sale

Transaction value: $655,145
Shares: -6,439
Change %: -2.2%
Price: $101.75
Shares after: 282,819
Date: 14 Sep 2026
Ownership: Direct
Footnotes: F1, F3

RYTM transaction

Common Stock

Sale

Transaction value: $3,146,761
Shares: -30,746
Change %: -11%
Price: $102.35
Shares after: 252,073
Date: 14 Sep 2026
Ownership: Direct
Footnotes: F1, F4

RYTM transaction

Common Stock

Sale

Transaction value: $899,634
Shares: -8,698
Change %: -3.5%
Price: $103.43
Shares after: 243,375
Date: 14 Sep 2026
Ownership: Direct
Footnotes: F1, F5

RYTM transaction

Common Stock

Sale

Transaction value: $189,965
Shares: -1,817
Change %: -0.75%
Price: $104.55
Shares after: 241,558
Date: 14 Sep 2026
Ownership: Direct
Footnotes: F1, F6

RYTM transaction

Common Stock

Sale

Transaction value: $241,937
Shares: -2,300
Change %: -0.95%
Price: $105.19
Shares after: 239,258
Date: 14 Sep 2026
Ownership: Direct
Footnotes: F1, F7

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

RYTM transaction Derivative

Employee Stock Option (Right to Buy)

Options Exercise

Transaction value
Shares: -50,000
Change %: -76%
Price: $0.000000^*
Shares after: 15,431
Date: 14 Sep 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 50,000
Exercise price: $6.05
Footnotes: F8

^* 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 8 footnotes

Footnote F1

The exercise and sales reported in this form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 15, 2026.

Footnote F2

Includes 242 shares acquired under the Rhythm Pharmaceuticals, Inc. employee stock purchase plan on 2-28-2026.

Footnote F3

The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $100.96 to $101.95 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 $101.96 to $102.94 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 $102.97 to $103.96 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 F6

The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $103.97 to $104.94 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 F7

The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $105.00 to $105.31 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 F8

The stock options were granted on February 8, 2017 and vested and became exercisable in three equal annual installments measured from January 6, 2017.