Zenas BioPharma Announces Positive Results from Phase 3 INDIGO Registrational Trial of Obexelimab in Immunoglobulin G4-Related Disease (IgG4-RD)

Core Insights - Zenas BioPharma announced positive results from the Phase 3 INDIGO trial of obexelimab, showing a 56% reduction in the risk of IgG4-RD flare compared to placebo, with a Hazard Ratio of 0.44 and p=0.0005 [1][2] - Obexelimab demonstrated statistically significant activity on all four key secondary efficacy endpoints, including reduction in flares requiring rescue therapy and the proportion of patients achieving complete remission [1][2] - The company plans to submit a Biologics License Application (BLA) to the FDA in Q2 2026 and a Marketing Authorization Application (MAA) to the EMA in H2 2026 [1][2] Company Overview - Zenas BioPharma is a clinical-stage global biopharmaceutical company focused on developing therapies for autoimmune diseases [15] - The company is advancing two late-stage product candidates: obexelimab and orelabrutinib, with obexelimab being the lead candidate targeting IgG4-RD [15] - Zenas aims to address the unmet medical needs of patients with autoimmune diseases through innovative therapies [15] Clinical Trial Details - The Phase 3 INDIGO trial enrolled 194 patients and was designed to evaluate the safety and efficacy of obexelimab over a 52-week period [10] - The primary endpoint was the time to first IgG4-RD flare requiring rescue therapy, with key secondary endpoints including the number of flares and the cumulative use of rescue therapy [11][12] - Obexelimab was well tolerated, with lower rates of infections and similar incidence of injection site reactions compared to placebo [1][2] Future Developments - Zenas expects to report topline results from the Phase 2 SunStone trial in Systemic Lupus Erythematosus (SLE) in Q4 2026 [4] - The company is also studying orelabrutinib in a global Phase 3 trial for Primary Progressive Multiple Sclerosis (PPMS) and plans to initiate a trial for non-active Secondary Progressive Multiple Sclerosis (naSPMS) in Q1 2026 [4] - Zenas is preparing to initiate Phase 1 clinical development for two additional product candidates, ZB021 and ZB022, in 2026 [4]