Infliximab and vedolizumab are widely used to treat Crohn's disease (CD) and ulcerative colitis (UC).This systematic review and network meta-analysis evaluated comparative efficacy of various regimens for intravenous or subcutaneous infliximab and vedolizumab during maintenance treatment in CD and UC.Parallel-group randomized controlled trials (RCTs) were identified by a systematic literature review (CRD42022383401) and included if they evaluated therapeutics of interest for maintenance treatment of adults with moderate-to-severe luminal CD or UC and assessed clinical remission between Weeks 30 and 60. Clinical remission rates in CD or UC and mucosal healing rates in UC were analyzed in a Bayesian network meta-analysis model. Endoscopic outcomes in CD were synthesized by proportional meta-analysis.Overall, 13 RCTs were included in the analyses. All vedolizumab studies randomized induction responders to maintenance treatment; infliximab studies used a treat-through design. Subcutaneous infliximab 120 mg every 2 weeks had the highest odds ratio (OR) [95% credible interval] versus placebo for clinical remission during the maintenance phase (CD: 5.90 [1.90-18.2]; UC: 5.45 [1.94-15.3]), with surface under the cumulative ranking curve (SUCRA) values of 0.91 and 0.82, respectively. For mucosal healing in UC, subcutaneous infliximab 120 mg every 2 weeks showed the highest OR (4.90 [1.63-14.1]), with SUCRA value of 0.73, followed by intravenous vedolizumab 300 mg every 4 weeks (SUCRA value, 0.70). Endoscopic outcomes in CD were better with subcutaneous infliximab 120 mg every 2 weeks than intravenous infliximab 5 mg/kg every 8 weeks.Subcutaneous infliximab showed a favorable efficacy profile for achieving clinical remission and endoscopic outcomes during maintenance treatment in CD or UC.