Spero Therapeutics, Inc. filed a Form 8-K on November 10, 2026, disclosing the resignation of director Patrick Vink, M.D., and the appointment of William Ho, M.D., Ph.D., as a Class II director, both effective November 10, 2026.

Key Highlights

  • Resignation: Patrick Vink, M.D., resigned as a Class II director, Chair of the Nominating and Corporate Governance Committee, and member of the Compensation Committee, effective November 10, 2026, after 11 years of service.
  • New appointment: William Ho, M.D., Ph.D., was appointed as a Class II director and member of the Development Committee, effective November 10, 2026.
  • Stock option grant: Dr. Ho received an option to purchase 100,000 shares of common stock, vesting over one year in equal monthly installments.
  • Annual retainer: Dr. Ho will receive a $40,000 annual cash retainer for Board service, plus an additional $5,000 for service on the Development Committee.
  • Prior role: Dr. Ho served as Chief Medical Officer of RAPT Therapeutics from 2015 to December 2025, where his work contributed to GSK's $2.2 billion acquisition of RAPT Therapeutics, finalized in March 2026, according to the filing.
  • No dispute: According to the filing, Dr. Vink's resignation "was not the result of any dispute or disagreement" with the Company, management, or any other Board member.

Board Transition at Spero Therapeutics: Vink Out, Ho In as Class II Director

According to the Form 8-K filed with the SEC by Spero Therapeutics, Inc. (NASDAQ:SPRO) on November 10, 2026, Patrick Vink, M.D., notified the Board of Directors on November 9, 2026, of his decision to resign from all director roles, including his positions with Company subsidiaries, effective November 10, 2026. The filing states that his departure "was not the result of any dispute or disagreement" on any matter relating to the Company's operations, policies, or practices, and the Company acknowledged 11 years of service from Dr. Vink.

On the same date, November 9, 2026, the Board appointed William Ho, M.D., Ph.D., upon the recommendation of the Nominating and Corporate Governance Committee, to fill the vacancy left by Dr. Vink as a Class II director. Dr. Ho was simultaneously appointed to the Development Committee. The filing describes Dr. Ho as "a physician-scientist and biotech executive with more than 20 years of clinical development experience across oncology, allergy, and immunology." Prior to RAPT Therapeutics, he held roles at Igenica Biotherapeutics and spent seven years at Genentech Research and Early Development in BioOncology, reaching Senior Medical Director. He holds an A.B. in Molecular Biology from Princeton University and an M.D. and Ph.D. in Microbiology and Immunology from Stanford University School of Medicine.

In connection with his appointment, Dr. Ho entered into the Company's standard form of Indemnification Agreement, the form of which was filed as Exhibit 10.7 to the Company's Annual Report on Form 10-K filed with the SEC on March 26, 2026. The filing states there are no arrangements or understandings between Dr. Ho and any other person pursuant to which he was selected, and that Dr. Ho is not a party to any transaction required to be disclosed under Item 404(a) of Regulation S-K.

What Was Disclosed

Spero Therapeutics disclosed the resignation of Class II director Patrick Vink, M.D., and the appointment of William Ho, M.D., Ph.D., as his replacement, along with Dr. Ho's compensation terms including a $40,000 annual retainer, a $5,000 Development Committee retainer, and an option to purchase 100,000 shares vesting monthly over one year.