Overview
- The company released 44‑week ABTECT maintenance results on Tuesday showing clinical remission in about 50.8% of patients at 25 mg and 51.3% at 50 mg versus 10.4% for placebo, figures analysts called unusually high for an oral ulcerative colitis therapy.
- Investigators reported several malignancies concentrated in the higher 50 mg arm, including individual cases of prostate and breast cancer, colonic dysplasia, and multiple non‑melanoma skin cancers.
- Abivax and trial investigators said the cancer cases were judged unrelated or unlikely related to treatment and reported no organ‑specific clustering, and the company reaffirmed plans to file for U.S. approval in late 2026 with a commercial target in 2027.
- Markets reacted sharply to the safety signal as shares fell about 30–40%, analysts cut ratings and flagged a possible labeling overhang, short interest and trading volume spiked, and a securities firm opened a shareholder investigation.
- The next drivers are the full safety appendix expected in coming months and the FDA review, which will shape labeling, prescribing decisions, potential deals from larger drugmakers, and whether patients gain access to a high‑efficacy oral option.