Abivax to Present Data on Obefazimod at Digestive Disease Week^®

Presentations Highlight Comprehensive Efficacy, Safety, and Patient-Reported Outcomes from the Phase 3 ABTECT Program and Preclinical Anti-Fibrotic Models in Inflammatory Bowel Disease

PARIS, France – April 22, 2026 – 10:05 pm CEST – Abivax SA (Euronext Paris: FR0012333284 – ABVX / 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 that nine scientific abstracts on obefazimod, its lead drug candidate for the treatment of moderately to severely active ulcerative colitis (UC), will be presented at the 2026 Digestive Disease Week (DDW) taking place May 2-5, 2026 in Chicago, IL. These presentations will highlight data from the Phase 3 ABTECT program, including efficacy, safety, and patient-reported outcomes, along with preclinical anti-fibrotic activity in two preclinical fibrosis models.

Fabio Cataldi, MD, Chief Medical Officer of Abivax, said: “The data being presented at this conference reinforce our confidence in obefazimod as a meaningful advancement for patients living with ulcerative colitis. From histologic and endoscopic outcomes to patient-reported improvements in fatigue and quality of life, these abstracts paint a comprehensive picture of a therapy with potential to address what matters most to patients and clinicians alike. We continue to be encouraged by the findings across the spectrum of disease severity and line of therapy."

Marc de Garidel, MBA, Chief Executive Officer of Abivax, added: “Our presence at DDW with nine abstracts highlights the depth and growing strength of the obefazimod dataset we are building in inflammatory bowel disease. These findings contribute to a more comprehensive understanding of its potential and support our ongoing efforts to bring meaningful innovation to patients.”

Visit the publications page of our website to view the presentations after the conclusion of the meeting.

Obefazimod Data to be Presented:

Date & Time Session Abstract # Title Presenter Oral Presentation Mon, May 4, 10:00-10:15 Controlled Clinical Trials 1 4470489 Impact of obefazimod treatment on histologic and combined histologic-endoscopic outcomes in patients with moderately to severely active UC: results from the ABTECT-1 and ABTECT-2 phase 3, double-blind, placebo-controlled induction trials Prof. Fernando Magro, MD, PhD

Head of the Department of Clinical Pharmacology and Professor of Pharmacology and Therapeutics at University Hospital São João in Porto, Portugal
 
  Poster Presentation Mon, May 4
12:30-1:30 Controlled Clinical Trials of IBD Treatment
  Mo1513
  Early symptomatic improvement with obefazimod in patients with moderately to severely active UC: pooled results from the ABTECT-1 and ABTECT-2 phase 3, double-blind, placebo-controlled induction trials Prof. Marla Dubinsky, MD
 
Professor of Pediatrics and Medicine, Chief, Division of Pediatric Gastroenterology and Nutrition
  Mon, May 4
12:30-1:30 Controlled Clinical Trials of IBD Treatment
  Mo1533 Efficacy and safety of obefazimod in an elderly population with moderately to severely active UC: week 8 results from the ABTECT-1 and ABTECT-2 phase 3, double-blind, placebo-controlled induction trials Andres J Yarur, MD
 
Associate Professor of Medicine, Cedars-Sinai Medical Center Mon, May 4
12:30-1:30 Controlled Clinical Trials of IBD Treatment
  Mo1522
  Efficacy of obefazimod in patients with moderately to severely active ulcerative colitis: results in subgroups of prior inadequate response to advanced therapy (AT-IR) including or excluding patients with prior JAK-IR from ABTECT phase 3 induction trials Prof. Bruce E Sands, MD, MS
 
Professor of Medicine, Icahn School of Medicine at Mount Sinai
  Mon, May 4
12:30-1:30
  Controlled Clinical Trials of IBD Treatment
  Mo1525 Integrated summary of safety of obefazimod in phase 3 ABTECT induction trials
  Prof. Bruce E Sands, MD, MS
 
Professor of Medicine, Icahn School of Medicine at Mount Sinai
  Mon, May 4
12:30-1:30
  Quality of Life and Psychosocial Outcomes Mo1677
  Improvements in patient-reported fatigue among patients with moderately to severely active UC treated with obefazimod: pooled results from the 8-week ABTECT-1 and ABTECT-2 phase 3 double-blind, placebo-controlled induction trials
  Prof. Marla Dubinsky, MD
 
Professor of Pediatrics and Medicine, Chief, Division of Pediatric Gastroenterology and Nutrition
  Mon, May 4
12:30-1:30
  Quality of Life and Psychosocial Outcomes Mo1667
  Improvements in patient-reported, disease-specific and overall quality-of-life among patients with moderately to severely active UC treated with obefazimod: pooled results from the 8-week ABTECT-1 and ABTECT-2 phase 3 induction trials Prof. Bruce E Sands, MD, MS
 
Professor of Medicine, Icahn School of Medicine at Mount Sinai Tue, May 5
12:30-1:30
  Mechanisms of IBD Therapeutics
  Tu1433
  Obefazimod shows first evidence of dual anti-inflammatory and anti-fibrotic activity in murine in vivo and human in vitro models
  Prof. Silvio Danese, MD, PhD

Director of Gastroenterology and Gastrointestinal Endoscopy Unit at IRCCS San. Raffaele Hospital Tue, May 5
12:30-1:30
  Mechanisms of IBD Therapeutics Tu1449 Obefazimod enhances mir-124 expression in blood and colon tissue and reduces the key inflammatory cytokines IL-17A and
IL-6 in serum of patients with moderate-to-severely active UC: results from the phase 3 ABTECT induction trials Parambir S Dulai, MD
 
Associate Professor, Feinberg School of Medicine at Northwestern University

 

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.

Contact:
Patrick Malloy
SVP, Investor Relations
Abivax SA
patrick.malloy@abivax.com
+1 847 987 4878

Media Contact:
LifeSci Communications
Karissa Baltz, Ph.D.
Associate Director
LSC_ABIVAX@lifescicomms.com

FORWARD-LOOKING STATEMENTS

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