Anaptys Announces Rosnilimab Achieved Positive Results in RA Phase 2b Trial and Highest Ever Reported CDAI LDA Response Over 6 Months

Core Insights - AnaptysBio, Inc. announced statistically significant Week 12 data from the Phase 2b RENOIR trial for rosnilimab, a treatment for moderate-to-severe rheumatoid arthritis (RA) [1][4][9] - Rosnilimab demonstrated a favorable safety profile, with adverse event rates similar to placebo [1][12][13] Group 1: Trial Overview - The Phase 2b RENOIR trial involved 424 patients with moderate-to-severe RA, assessing the efficacy, safety, and pharmacokinetics of rosnilimab [2][4] - Patients were randomized to receive different doses of rosnilimab or placebo, with primary and secondary endpoints evaluated at Weeks 12 and 14 [3][4] Group 2: Efficacy Results - Rosnilimab achieved its primary endpoint with a mean change from baseline in DAS-28 CRP at Week 12 for all doses compared to placebo [4][7] - Key secondary endpoints, including ACR20, ACR50, and CDAI LDA, showed statistical significance at Week 12, with 69% of patients achieving CDAI LDA at Week 14 [5][7][10] Group 3: Pharmacological Activity - Translational blood biomarker data indicated a robust pharmacological effect, with a ~90% reduction in PD-1 T cells and a ~50% reduction in PD-1+ T cells observed in rosnilimab-treated patients [6][8] - The treatment resulted in a favorable T cell composition and a ~50% reduction in mean CRP levels, indicating effective inflammation control [6][8] Group 4: Safety Profile - The safety data through Week 12 showed that 48% of patients on 100mg Q4W, 45% on 400mg Q4W, and 36% on 600mg Q2W experienced any adverse events, comparable to 34% in the placebo group [12][13] - No malignancies or major adverse cardiovascular events were reported, and the incidence of serious infections was similar to placebo [13][14] Group 5: Future Outlook - Full Week 28 data and additional translational data are expected in Q2 2025, with top-line data for ulcerative colitis anticipated in Q4 2025 [7][9][20] - The company aims to address the unmet need for innovative RA therapies, highlighting the potential of rosnilimab to provide durable relief and disease modification [11][14]