Altimmune, Inc. filed a Form 8-K on October 27, 2026, disclosing the appointment of Peter Greenleaf and Alex Howarth as directors effective November 2, 2026, and the planned retirements of three existing board members ahead of the company's 2027 annual meeting.

Key Highlights

  • Board expanded: The Board approved an increase in its size from nine to eleven directors, effective November 2, 2026.
  • Greenleaf appointed: Peter Greenleaf (54), most recently CEO of Aurinia Pharmaceuticals Inc. (Nasdaq: AUPH), was appointed as a director.
  • Howarth appointed: Alex Howarth (58), most recently CFO of Madrigal Pharmaceuticals, Inc. (Nasdaq: MDGL), was appointed as a director.
  • Initial equity grants: Each new director will receive stock options to purchase 160,000 shares of common stock under the company's 2017 Omnibus Incentive Plan.
  • Annual cash retainer: Each new director is entitled to an annual cash retainer of $40,000 as a board member.
  • Three directors to retire: John Gill, Mitchell Sayare, and Dr. Klaus Schafer each notified the Board of their decision to retire and not stand for re-election at the 2027 annual meeting of stockholders.

Altimmune Board Composition Changes: Appointments and Planned Retirements

According to the filing, Altimmune, Inc. (NASDAQ:ALT) disclosed on October 23, 2026 that its Board of Directors, acting on the recommendation of its Nominating and Corporate Governance Committee, appointed Peter Greenleaf and Alex Howarth as directors, with both appointments effective November 2, 2026. The Board simultaneously approved expanding its membership from nine to eleven seats.

The filing describes Greenleaf's background as including the role of President at MedImmune LLC, the global biologics arm of AstraZeneca, from 2006 to 2013, as well as CEO positions at Sucampo Pharmaceuticals, Inc., Cerecor Pharmaceuticals, Inc., and Histogenics Corporation. The filing notes that he currently serves as Chairman of the board of directors of Pelthos Therapeutics, Inc. (NYSE: PTHS) and as a member of the board of Revolo Biotherapeutics. Howarth's background, as described in the filing, includes serving as CFO of Madrigal Pharmaceuticals from May 2021 through May 2024, and previously as Chief Operating Officer of Akcea Therapeutics, Inc. (Nasdaq: AKCA). The filing states that Howarth earned a Bachelor of Applied Science in Biochemistry from the University of Bath and qualified as a Chartered Accountant in the United Kingdom.

Both new directors will be compensated under the company's Non-Employee Director Compensation Policy, according to the filing. Additionally, the company entered into indemnification agreements with each of them in substantially the same form as those held by other directors. The filing also states that on October 23, 2026, John Gill, Mitchell Sayare, and Dr. Klaus Schafer each notified the Board of their intent to retire and not stand for re-election at the 2027 annual meeting. The filing specifies that their departures are "not due to any disagreement with the Company on any matter relating to the Company's operations, policies or practices."

What Was Disclosed

Altimmune filed an 8-K on October 27, 2026, reporting the appointment of two new directors effective November 2, 2026, a board size increase from nine to eleven, the compensation terms for the incoming directors, and the retirement notices from three current directors ahead of the 2027 annual meeting.