Abivax Shares Surge 36% After Positive Phase 3 Trial Results for Ulcerative Colitis Drug

Shares of French biotechnology company Abivax soared 36% on Tuesday after the company announced encouraging Phase 3 clinical trial results for its experimental ulcerative colitis treatment, obefazimod. The positive update renewed investor optimism following a sharp decline in the company's stock earlier this month.

Abivax reported that the latest findings from the maintenance phase of its Phase 3 ABTECT trial demonstrated that obefazimod delivered clinically meaningful benefits for adults with moderate to severe ulcerative colitis, including patients who had previously failed to respond to treatment.

According to the company, 37.2% of patients who did not initially respond to therapy achieved clinical remission after 44 weeks of treatment, while 34.5% experienced healing of the intestinal lining. Among patients whose symptoms returned after an initial response, increasing the dosage to 50 mg helped 45.5% regain remission.

The company also released updated safety data, stating that long-term analysis found no new or unexpected safety concerns. Cancer incidence remained within the expected range for patients with ulcerative colitis, based on combined Phase 2 and Phase 3 data representing approximately 1,704 patient-years of treatment exposure.

Chief Executive Marc de Garidel said the expanded safety findings strengthen confidence in obefazimod's long-term safety profile and support the company's plans to seek regulatory approval in the United States later this year.

The positive announcement comes less than a month after Abivax shares fell 44% following the release of earlier maintenance trial safety data, highlighting investor sensitivity to developments surrounding the company's lead drug candidate.

Abivax confirmed it remains on schedule to submit a New Drug Application (NDA) for obefazimod to the U.S. Food and Drug Administration (FDA) during the fourth quarter of 2026.

Beyond ulcerative colitis, the company is also evaluating obefazimod as a potential treatment for Crohn's disease, another chronic inflammatory bowel disorder. Mid-stage Phase 2 trial results for that program are expected in mid-2027, potentially expanding the drug's future commercial potential.

Following the announcement, Abivax shares were trading at €113.30 on the Paris market, reflecting renewed investor confidence in the company's late-stage development program.