A Study of Efficacy and Safety of Rosnilimab in Subjects With Moderate to Severe Ulcerative Colitis (ROSETTA)
- Resolved Date
- 11/10/25
- Study Completion
- 5/1/26
- Company
- AnaptysBio, Inc.
- Ticker
- ANAB
- Type
- Trial Status
- Active Not Recruiting
- Trial Size
- 132
- Volume
- $0
- NCT
- NCT06127043
- Drug Description
- ROSETTA STUDY: This study will evaluate the safety, tolerability, and efficacy of Rosnilimab in subjects with moderate to severe ulcerative colitis (UC)
- Outcome
- NO
- Status
- Resolved
- Settlement Date
- 3/30/26 UTC
- Executive Summary
Public topline data for the exact Phase 2 ROSETTA ulcerative colitis trial were reported in November 2025, and the sponsor clearly framed the readout as negative: rosnilimab did not meet the primary endpoint or key secondary endpoints, showed no better efficacy than placebo at Week 12, and the UC trial was discontinued.
AnaptysBio announced that investigational rosnilimab was safe and well tolerated but did not meet the primary endpoint of mean change from baseline in modified Mayo Score or key secondary endpoints of clinical response and clinical remission at Week 12 in the global Phase 2 trial for moderate-to-severe ulcerative colitis. The company said the UC trial will be discontinued.
Fierce Biotech reported that AnaptysBio abandoned plans to develop rosnilimab for ulcerative colitis after the drug flunked a phase 2 study. The article states that remission rates were no better than placebo and quotes the CEO saying they were disappointed in the lack of adequate efficacy and would discontinue the UC trial.
