Yann Mazabraud, EVP and Head of International at Rhythm Pharmaceuticals, Inc., filed a Form 4 on August 14, 2026, disclosing a stock option exercise and the sale of common shares on August 12, 2026, all executed under a pre-established Rule 10b5-1 trading plan.

Key Highlights

  • Option exercise: Mazabraud exercised stock options covering 46,625 shares of common stock at an exercise price of $6.8 per share on August 12, 2026.
  • Shares sold: A total of 57,000 shares were sold across six tranches on August 12, 2026, at weighted average prices ranging from $111.7992 to $117.4686 per share.
  • Remaining ownership: Following all reported transactions, Mazabraud directly holds 55,655 shares of common stock and 35,875 stock options.
  • Trading plan: All transactions were made pursuant to a Rule 10b5-1 trading plan adopted by Mazabraud on May 13, 2026.
  • Option grant details: The exercised options were originally granted on February 9, 2022, vesting in 16 substantially equal installments every three months of successive service, with an expiration date of February 8, 2032.

Details of Mazabraud's August 2026 Option Exercise and Share Sales at Rhythm Pharmaceuticals

According to the filing, Yann Mazabraud, who serves as EVP and Head of International at Rhythm Pharmaceuticals, Inc. (NASDAQ:RYTM), exercised stock options for 46,625 shares of common stock on August 12, 2026, at an exercise price of $6.80 per share (transaction code M). Prior to this exercise, the filing indicates the acquisition brought his directly held common stock to 112,655 shares.

The filing further discloses that Mazabraud then sold shares across six separate tranches on the same date. The sales, each coded "S," totaled 57,000 shares: 2,300 shares at a weighted average price of $111.7992, 1,000 shares at $112.856, 3,605 shares at $114.6955, 14,568 shares at $115.427, 18,208 shares at $116.4941, and 17,319 shares at $117.4686. The filing notes that each reported price is a weighted average, with the underlying individual transaction prices available upon request to the issuer, any security holder, or SEC staff.

The filing states that all exercises and sales "were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 13, 2026." After all transactions, Mazabraud directly holds 55,655 shares of common stock and retains 35,875 stock options. The options exercised were granted on February 9, 2022, and vest in 16 substantially equal installments upon completion of each three full months of successive service following the grant date.

What Was Disclosed

The Form 4 filed August 14, 2026, covers an option exercise of 46,625 shares at $6.80 and the sale of 57,000 common shares at weighted average prices between $111.7992 and $117.4686, all on August 12, 2026, under a Rule 10b5-1 plan.