Abivax Announces Appointment of Dominik Höchli, MD to Board of Directors

Industry veteran brings deep immunology expertise ahead of key Phase 3 data readout in ulcerative colitis expected in Q3 2025

PARIS, France, April 22, 2025, 10:00 pm CEST – Abivax SA (PARIS:FR, NASDAQ:ABVX) ("Abivax" or the "Company"), a clinical-stage biotechnology company focused on developing therapeutics that harness the body's natural regulatory mechanisms to stabilize the immune response in patients with chronic inflammatory diseases, today announced the appointment of Dominik Höchli, MD to the Board of Directors of Abivax, effective immediately.

Dr. Höchli brings over two decades of leadership experience in global biopharma, most notably a 20-year tenure at AbbVie/Abbott, where he served as Vice President of Global Marketing for Immunology and later as Head of Global Medical Affairs. His strategic expertise in medical affairs and product positioning—particularly within competitive immunology markets—will be instrumental as Abivax prepares for the upcoming Phase 3 data readout for the 8-week induction trial in ulcerative colitis expected in Q3 2025.

In addition to his experience at AbbVie, Dr. Höchli served as Interim CEO of Catapult Therapeutics, a hematology-oncology company, from 2021 to 2024. He is also the founder of Abinode, a pharmaceutical strategy consulting firm, and currently serves on the Board of Directors at Molecular Partners AG, where he is a member of both the Audit Committee and the Research & Development Committee.

Sylvie Grégoire, Chair of Abivax Board of Directors, commented: "We are delighted to welcome Dominik to the Board at such a pivotal moment for Abivax. His extensive background in global medical strategy and commercialization within immunology will be invaluable as we approach key clinical and regulatory inflection points for obefazimod."

Dr. Dominik Höchli added: "I'm excited to join the Board at a time when Abivax is entering a critical phase of clinical development and to support the company's efforts to bring obefazimod to patients living with ulcerative colitis and Crohn's disease."

About Abivax

Abivax is a clinical-stage biotechnology company focused on developing therapeutics that harness the body's natural regulatory mechanisms to stabilize the immune response in patients with chronic inflammatory diseases. Based in France and the United States, Abivax's lead drug candidate, obefazimod (ABX464), is in Phase 3 clinical trials for the treatment of moderately to severely active ulcerative colitis. More information on the Company is available at www.abivax.com. Follow Abivax on LinkedIn and on X, formerly Twitter, Abivax.

Contact:

Patrick Malloy

SVP, Investor Relations, Abivax

patrick.malloy@abivax.com

+1 847 987 4878

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