Persistence and safety of subcutaneous infliximab up to 1 year after switching from intravenous infliximab in pediatric inflammatory bowel disease: a multicenter real-world cohort study

Abstract

Introduction: Real-world data regarding subcutaneous infliximab (SC-IFX) in patients with pediatric inflammatory bowel disease IBD (PIBD) is scarce. We evaluated SC-IFX as maintenance therapy in PIBD patients who switched to SC-IFX from intravenous infliximab (IV-IFX) treatment. Methods: In this retrospective multicenter study we identified PIBD patients who switched to SC-IFX. The primary outcome was treatment persistence at up to 12 months post-switch. Secondary outcomes included relapse rate (defined as Pediatric Ulcerative Colitis Activity Index [PUCAI] ≥10/ weighted PCDAI ≥ 12.5 with biochemical/endoscopic evidence of disease activity), IFX trough levels, immunogenicity, safety, and acceptance. Results: Sixty-six patients switched to SC-IFX (48% males; median switch-age, 16.5 years; IQR, 14.9-17.3 years; median switch-weight, 60 kg; range, 13-102 kg), 41/66 (62%) with Crohn Disease. Pre-switch, the median IV-IFX maintenance dose was 10 mg/kg every 6 weeks; 58/66 patients (88%) were in clinical remission. The initial SC-IFX regimen was 120 mg every other week in 62/66 patients (94%). SC-IFX persistence was 78% (95% CI, 66-91) at 12 months post-switch, with 89% of patients persisting on IFX, either intravenous (IV) or subcutaneous (SC), at the end of follow-up. Relapses were observed in 11/66 patients (17%) over a median follow-up of 11.0 months (IQR, 5.1-12.0); 6 patients underwent SC-IFX dose intensification, with 3 successfully regaining clinical response. Regarding anti-drug antibodies (ADA), 3 out of 4 patients who were ADA positive on IV-IFX resolved post-switch. Overall, 19/66 patients (29%) reported 21 adverse events (AEs), including 3/21 severe AEs. The majority (53/66 patients; 80%) expressed a positive attitude toward SC-IFX. Conclusions: The largest documented PIBD cohort switching to SC-IFX to date showed high treatment persistence at 1 year, confirming SC-IFX as an effective and safe maintenance alternative to IV-IFX.