AnaptysBio To Save $10 Million After Discontinuing Ulcerative Colitis Study

Core Insights - AnaptysBio Inc. announced data from the Phase 2 trial of rosnilimab for moderate-to-severe ulcerative colitis, indicating that the drug did not meet its primary or key secondary endpoints [2][5]. Trial Results - Rosnilimab was found to be safe and well-tolerated, but it performed no better than placebo at Week 12, with clinical remission rates of 7% for patients receiving 400mg Q4W and 800mg Q2W, compared to 5% and 4% for endoscopic remission [2][5]. - The placebo rates in the trial were within expected historical ranges [2]. - Preliminary data suggested an increase in remission rates between Week 12 and Week 24, but these rates did not meet the six-month target product profile [5]. Financial Implications - The company will discontinue the ulcerative colitis trial, resulting in at least $10 million in savings [3]. Future Plans - AnaptysBio remains optimistic about the potential of rosnilimab in rheumatoid arthritis (RA) and plans to provide an update in H1 2026, including funding strategies that do not dilute royalties [4]. - The company is also conducting a Phase 1b study for ANB033 for celiac disease and plans to announce another Phase 1b study in a different inflammatory disease in 2026 [7]. Market Reaction - Following the announcement, AnaptysBio shares fell by 13.63%, trading at $34.24 [8]. Strategic Moves - AnaptysBio reiterated its intention to separate biopharma assets from substantial royalty assets in 2026, including expected royalties of over $390 million per year from Jemperli at GSK's peak sales guidance of over $2.7 billion [8].