Abivax SA said its oral drug obefazimod met the primary endpoint in a Phase 3 maintenance trial for moderately to severely active ulcerative colitis, with 50.8% of patients on the 25-milligram dose achieving clinical remission at 44 weeks compared with 10.4% on placebo.
"The results highlight the exceptional potential of obefazimod to redefine the treatment landscape for ulcerative colitis," Marc de Garidel, chief executive officer of Abivax, said in a statement.
The ABTECT maintenance trial enrolled 580 patients who had responded to an initial eight-week induction period and re-randomized them to receive 25 mg obefazimod, 50 mg obefazimod, or placebo once daily. The 50 mg dose produced a 51.3% remission rate, yielding a 40.3 percentage-point placebo-adjusted difference. Both doses also met all key secondary endpoints — including endoscopic improvement, endoscopic remission, histologic-endoscopic mucosal improvement, corticosteroid-free clinical remission, and sustained clinical remission — all with p<0.0001. The 10.4% placebo remission rate was the lowest reported to date in a Phase 3 ulcerative colitis maintenance trial using a responder re-randomization design, according to the company.
Obefazimod is a first-in-class oral miR-124 enhancer that harnesses the body's natural regulatory mechanisms to stabilize the immune response in chronic inflammatory diseases. The safety profile was generally favorable with no new signals, though the 50 mg arm recorded three malignancies — one case each of prostate cancer, breast cancer, and colonic dysplasia — plus three non-melanoma skin cancers. No cases of cardiac fibrosis or acute pancreatitis were observed. The 25 mg arm had one squamous cell carcinoma and no other malignancies. Serious treatment-emergent adverse events occurred in 2.6% of the 25 mg group, 5.6% of the 50 mg group, and 4.2% of the placebo group.
The results position obefazimod as a potential competitor to established therapies including AbbVie's Humira, Takeda's Entyvio, and Johnson & Johnson's Stelara in the multi-billion-dollar inflammatory bowel disease market. Leerink analyst Thomas Smith noted the study posted the highest placebo-adjusted clinical remission rates observed in a long-term ulcerative colitis trial, according to STAT. Abivax plans to submit a New Drug Application to the FDA in late fourth quarter 2026. The company's shares fell in post-market trading after the disclosure of malignancy cases in the treatment arms, though the overall efficacy data exceeded historical benchmarks.
This article is for informational purposes only and does not constitute investment advice.