Switching to Subcutaneous Infliximab Maintenance Therapy Is Effective in Patients with Inflammatory Bowel Disease

Background Recent studies suggest that subcutaneous infliximab is effective and safe for treating patients with inflammatory bowel disease. Real-world studies with larger cohorts are needed to confirm the efficacy of subcutaneous treatment. Aims The aim was to assess real-world treatment persistence, clinical outcomes, infliximab concentrations, and treatment safety after switching from intravenous to subcutaneous infliximab treatment with patients with inflammatory bowel disease. Methods This retrospective register-based study included patients with inflammatory bowel disease who were in clinical remission and switched from intravenous infliximab maintenance therapy to subcutaneous infliximab in two tertiary centers. Results A total of 274 patients (104 Crohn's disease and 170 ulcerative colitis) were included. After the switch, the treatment persistence at 12 months was 94.8% in patients with Crohn's disease and 88.8% in patients with ulcerative colitis. Only 11.3% (n = 31) of the patients discontinued the treatment during 79-week median follow-up. Compared to the baseline, no change occurred in clinical disease activity at the time points of 3, 6, and 12 months, based on the Harvey-Bradshaw Index or partial Mayo Score (p = 0.792 and p = 0.426, respectively). Infliximab median concentrations were higher (p < 0.0001) during subcutaneous treatment (16.75 <mu>g/ml) compared to the intravenous treatment median trough levels before the switch (6.71 mu g/ml). In total, 15.0% (n = 41) of the patients reported adverse events. Conclusion Switching to subcutaneous infliximab maintenance therapy was associated with high treatment persistence, a stable disease course, increased infliximab concentrations, and an acceptable safety profile.