S1505 Efficacy and Safety of Guselkumab Through Week 96 After Intravenous or Subcutaneous Induction in Participants With Crohn’s Disease: Phase 3 Long-Term Extension Data From GALAXI 2, GALAXI 3, and GRAVITI

Introduction: Guselkumab (GUS), a dual-acting IL-23p19 subunit inhibitor, is highly efficacious in participants (pts) with Crohn’s disease (CD). Phase 3 studies (GALAXI 2, GALAXI 3, and GRAVITI) showed that GUS administered via intravenous (IV) or subcutaneous (SC) induction followed by SC maintenance has similar efficacy after induction and through week (W)48. We report GUS W96 efficacy data from the long-term extension (LTE) periods of these studies and safety data from W0 to W96. Methods: The studies had double-blind, placebo-controlled, treat-through designs with blinding until the W48 database lock. GALAXI 2 and 3 evaluated IV GUS induction (200 mg at W0, W4, and W8) followed by SC maintenance (100 mg every 8 weeks or 200 mg every 4 weeks). GRAVITI assessed SC GUS induction (400 mg at W0, W4, and W8) and the same GUS maintenance regimens used in GALAXI. Pts entered the LTE receiving the treatment they received at W48. Between W52 and W80 (GALAXI only), pts on GUS 100 mg SC every 8 weeks who were not in clinical response received dose escalation to 200 mg SC every 4 weeks; pts on GUS 200 mg SC every 4 weeks received a “sham” adjustment to GUS 200 mg SC every 4 weeks. Efficacy analyses included all pts randomized at W0 with a Simple Endoscopic Activity Score for CD (SES-CD) ≥6 (≥4 for pts with isolated ileal disease) who received ≥1 study drug dose. Pts with missing data or who met treatment failure criteria were considered non-responders. As observed data are also presented. Safety analyses comprised all randomized pts who received study drug. Results: Between W0 and W96, 127/582 pts (21.8%) from GALAXI 2 and 3 and 31/230 pts (13.5%) from GRAVITI discontinued treatment. Across studies, high rates of long-term endoscopic response, endoscopic remission, clinical remission, and deep remission were observed after treatment with both GUS doses. Respective W96 rates for IV vs SC induction were 44.1% vs 47.8% (100 mg SC every 8 weeks) and 44.6% vs 59.1% (200 mg SC every 4 weeks) for endoscopic response, 28.3% vs 38.3% (100 mg SC every 8 weeks) and 31.4% vs 47.0% (200 mg SC every 4 weeks) for endoscopic remission, 59.4% vs 62.6% (100 mg SC every 8 weeks) and 63.2% vs 71.3% (200 mg SC every 4 weeks) for clinical remission, and 26.2% vs 34.8% (100 mg SC every 8 weeks) and 29.4% vs 39.1% (200 mg SC every 4 weeks) for deep remission. Safety data through 2 years were comparable across studies and consistent with the safety profile of the label indications. Conclusion: Long-term efficacy outcomes show the durability of GUS treatment in CD through 2 years across multiple studies. No new safety concerns were identified.