INDIGO, the largest randomized, double-blind, placebo-controlled study conducted in IgG4-RD, met the primary endpoint demonstrating a highly statistically significant and clinically meaningful 56% reduction in the risk of IgG4-RD flare compared to placebo (HR 0.443; 95% CI 0.277–0.711; p=0.0005) during the 52-week randomized placebo-controlled period. Obexelimab also met and demonstrated highly statistically significant activity compared to placebo on all four key secondary endpoints: time to first investigator-determined flare requiring rescue therapy (p=0.0001), number of investigator- and AC-determined flares requiring rescue therapy (p=0.0008), proportion of patients achieving complete remission (p=0.0049), and cumulative glucocorticoid rescue therapy use (p=0.0042). Obexelimab was well tolerated with no new safety signals observed. Treatment-emergent adverse events (TEAEs) occurred in 97.9% vs 95.9% of participants (obexelimab vs placebo). Incidence of Grade ≥3 TEAEs was less with obexelimab (11.3% vs 23.7%), and the incidence of serious adverse events was 10.3% vs 18.6%. Infections occurred in 53.6% vs 62.9% of participants. Injection-site reactions were reported in 3.5% vs 2.3% of total patient doses. Hypersensitivity occurred in 16.5% vs 11.3% of participants. There were no deaths in the obexelimab group and one death (1.0%) in the placebo group.
Details of EULAR Presentation:
- Title: Obexelimab, a B Cell Inhibitor, in IgG4-Related Disease: Results From the Phase 3 INDIGO Trial
- Presenting Author: Emanuel Della Torre, M.D., Ph.D., Associate Professor of Rheumatology, Vita-Salute San Raffaele University, Milan, Italy
- Session: New Perspectives in IgG4-Associated Diseases
- Session Date & Time: Thursday, June 4, 2026, at 2:45 PM GMT
- Abstract Number: OP018
- Location: Excel London, Room N1