Abivax said Monday that its experimental treatment for ulcerative colitis showed significant efficacy in a closely watched maintenance trial, but shares of the company tanked in post-market trading as it reported a few cases of cancer among treated patients.
The Phase 3 trial enrolled 580 patients who had responded in a pair of earlier, shorter trials. The participants were then followed for 44 weeks, and 50.8% of those taking the 25-milligram dose of the daily pill, called obefazimod, experienced clinical remission, while 51.3% of those taking the 50-mg dose did, compared with 10.4% of those on placebo.
The study appears to have posted the highest placebo-adjusted clinical remission rates observed in a long-term ulcerative colitis trial, Leerink analyst Thomas Smith wrote.



