Abivax reports Part 2 maintenance data for obefazimod in ulcerative colitis

Abivax SA announced on June 29, 2026 positive topline results from Part 2 of its Phase 3 ABTECT 44-week maintenance trial evaluating obefazimod, the company's potential first-in-class oral miR-124 enhancer, in moderate to severely active ulcerative colitis.¹ Part 2 covered patients who did not respond to induction treatment or who relapsed during the earlier re-randomized Part 1 maintenance trial, and the company said this expanded both the efficacy and safety results in a more refractory patient population than the registrational maintenance cohort.¹

Among induction non-responders, patients treated continuously with 50 mg obefazimod showed clinical remission of 37.2%, clinical response of 61.5%, endoscopic improvement of 48.0%, HEMI of 44.6%, and endoscopic remission of 34.5% at Week 44.¹

Among patients who relapsed during Part 1, those who had responded to obefazimod during induction and then relapsed on placebo were switched to open-label 50 mg and reached clinical response of 69.7% and clinical remission of 45.0%; patients who relapsed on 25 mg and escalated to 50 mg reached response of 66.7% and remission of 45.5%.¹

On safety, across the combined Phase 2 and Phase 3 UC program spanning 1,704 patient-years, exposure-adjusted incidence rates for malignancies excluding non-melanoma skin cancer were 0.35 and 0.64 events per 100 patient-years, and for NMSC were 0.59 and 0.64 events per 100 patient-years, in the all-active combined and 50 mg cohorts respectively¹, which the company said were consistent with expected UC background rates. No new safety pattern emerged with the additional cumulative exposure provided by Part 2.¹

The company believes it remains on track to submit its NDA to the U.S. Food and Drug Administration in the fourth quarter of 2026.¹ Other milestones include half-year 2026 financial results on September 21, 2026, and mid-2027 topline results from the Phase 2b ENHANCE-CD induction trial in Crohn's disease.¹