Abivax’s Obefazimod Advances in Ulcerative Colitis Treatment
Paris, France – 12 January 2026 – Abivax SA has made significant strides in the development of obefazimod, its first-in-class oral miR-124 enhancer, for the treatment of moderately to severely active ulcerative colitis (UC). Following positive Phase 3 induction trial results announced in July 2025, the company is now awaiting topline data from the ongoing maintenance trial, expected in the second quarter of 2026.
Phase 3 Induction Trial Success
In July 2025, Abivax reported compelling results from the ABTECT-1 and ABTECT-2 trials, which enrolled 1,275 patients across 36 countries. The studies demonstrated that obefazimod achieved a pooled placebo-adjusted clinical remission rate of 16.4% at Week 8, meeting primary endpoints for the 50 mg dose. The drug also showed significant improvements in endoscopic improvement, clinical response, and histological endoscopic mucosal improvement. Safety data indicated a profile consistent with prior studies, with no new signals of concern.
Further analysis in November 2025 highlighted patient-reported outcomes, revealing substantial enhancements in quality of life, including reductions in bowel urgency, nocturnal bowel movements, and fatigue. These findings underscore obefazimod’s potential to address not only clinical symptoms but also the daily impacts of UC on patients.
Novel Mechanism of Action
Obefazimod works by enhancing the expression of microRNA-124 (miR-124), a natural regulator of inflammation. Discovered through research at Institut Curie in France, this mechanism stabilises the immune response by modulating cytokines and chemokines under dysregulated conditions. Unlike traditional therapies targeting specific pathways, obefazimod aims to restore immune homeostasis, potentially offering durable efficacy without compromising immune competence.
The drug’s development stems from Abivax’s proprietary chemical library and collaborations with institutions like the Institute of Molecular Genetics of Montpellier. It represents a pioneering approach in inflammatory bowel disease (IBD) treatment, differentiating it from biologics and JAK inhibitors.
Key Facts / Stats
| Metric | ABTECT-1 (50 mg) | ABTECT-2 (50 mg) | Pooled (50 mg) |
|---|---|---|---|
| Clinical Remission at Week 8 (%) | 21.7% | 19.8% | 20.8% |
| Placebo-Adjusted Remission (%) | 19.3% | 13.4% | 16.4% |
| Endoscopic Improvement at Week 8 (%) | 33.3% | 35.5% | 34.4% |
| Clinical Response at Week 8 (%) | 61.0% | 63.2% | 62.1% |
| Patients Enrolled | 639 | 636 | 1,275 |
Frequently Asked Questions
What is ulcerative colitis and how does obefazimod help?
Ulcerative colitis is a chronic inflammatory bowel disease affecting the colon and rectum, causing symptoms like abdominal pain, diarrhoea, and fatigue. Obefazimod enhances miR-124 expression to stabilise the immune response, reducing inflammation and promoting remission in patients with moderate to severe UC.
When will the maintenance trial results be available?
Topline results from the 44-week ABTECT maintenance trial are expected in the second quarter of 2026. These data will support regulatory filings with the FDA and EMA in the second half of 2026, contingent on positive outcomes.
Is obefazimod safe?
In the Phase 3 trials, obefazimod’s safety profile was consistent with earlier studies, with treatment-emergent adverse events similar to placebo. No new safety signals were observed, and serious adverse events were rare.