Abivax Announces Former Prometheus COO, Mark Stenhouse, Appointed as Board Observer & Advisor to Abivax PARIS, France, November 13, 2024, 10:00 pm CET – Abivax SA (Euronext Paris and 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 Mark Stenhouse as Board Observer and Advisor to Abivax. Mr. Stenhouse brings more than 30 years of experience in the biopharma industry.

Most recently, he served as Chief Operating Officer of Prometheus Biosciences, a biotechnology company focused on gastrointestinal diseases that was acquired by Merck for $10.8 billion in 2023. Prior to Prometheus, Mr.

Stenhouse spent over 25 years at AbbVie, most recently serving as Vice President of U.S. Immunology.

In this capacity, Mr. Stenhouse oversaw U.S.

sales and marketing teams for HUMIRA®. In addition to his positions at Prometheus and Abbvie, Mr. Stenhouse held an executive leadership role at Exact Sciences.

He holds a Bachelor of Science in Business Administration from the College of Charleston. Marc de Garidel, Chief Executive Officer of Abivax, said: “We are pleased to welcome Mark to the role of Board Observer and Advisor to Abivax. We expect his perspective and extensive experience in gastroenterology and immunology to undoubtedly support our contin.