Systematic review with meta-analysis of the effectiveness of subcutaneous biologics versus intravenous biologics in inflammatory bowel diseases.

BACKGROUND Biologic therapies are commonly used for inflammatory bowel disease (IBD) patients. Multiple biologic medicines can now be given both intravenously and subcutaneously. The different administration routes present provide different advantages regarding dose escalation, healthcare resource utilisation, pharmacokinetics, convenience and safety. Comparator effectiveness studies between intravenous and subcutaneous administration are lacking. AIM Our primary outcome was to compare the effectiveness between intravenous and subcutaneous biologics in rates of clinical remission. METHODS We performed a systematic review and meta-analysis to include all relevant articles from MEDLINE (Ovid), EMBASE, PubMed and Cochrane Central Register of Controlled Trials from 1 January 2003 to 28 January 2024. Studies that compared intravenous and subcutaneous administration of the same biologic therapy in IBD patients and reported effectiveness outcomes were included. This study was registered on PROSPERO (CRD42023442675). RESULTS Twenty studies met the inclusion criteria for the systematic review. Nine vedolizumab cohort studies were meta-analysed for clinical remission and no difference was found in clinical remission rates between intravenous and subcutaneous administration (relative risk = 0.99; 95% confidence interval: 0.88, 1.11). Six infliximab cohort studies were meta-analysed for clinical remission and no difference was found in clinical remission rates between intravenous and subcutaneous administration (relative risk = 0.91; 95% confidence interval: 0.77, 1.08). CONCLUSIONS Our findings in the first meta-analysis comparing the effectiveness of intravenous and subcutaneous biologic therapies in IBD suggest there is no difference in the effectiveness between these two administration routes. However, further high-quality studies, particularly head-to-head studies are needed to confirm this finding.