Systematic review with meta-analysis: infliximab and immunosuppressant therapy vs. infliximab alone for active ulcerative colitis

Background: The benefit of the combination of infliximab (IFX) and immunosuppressant (IS) therapy is debated in ulcerative colitis (UC).

Aims: To determine whether the combination of IFX and IS therapy is more effective than infliximab alone for active UC regardless of prior IS use.

Methods: We identified all controlled trials including patients with moderate-to-severe active UC, treated by either IFX or combined IFX-IS therapy. The main outcome was clinical remission at 4-6 months. Two statistical methods were used, Mantel-Haenszel and Der-Simonian and Laird. Inter-trial heterogeneity was taken into account and publication bias was assessed.

Results: Four controlled trials were analysed and included in the meta-analysis. These four trials included 765 patients, 389 treated with IFX alone and 376 treated with IFX and IS. At 4-6 months' therapy, the clinical remission rate was significantly lower for the IFX monotherapy group OR 0.50, 95% CI [0.34-0.73], P < 0.01 (P-heterogeneity = 0.49). The Harbord test did not show evidence of publication bias (P = 0.29). Calculation of an adjusted OR using the Duval and Tweedie method did not significantly modify results [OR 0.63, 95% CI (0.47-0.85)]. According to Orwin's formula, four additional medium-sized nonsignificant studies would be necessary to reduce the effect size to a nonsignificant value. At 12 months of therapy, there was no significant difference between the two groups: OR 0.60, 95% CI [0.17-2.06], P = 0.41 (P-heterogeneity = 0.01).

Conclusion: Combination therapy with IFX-IS is more effective than IFX alone for achieving and maintaining clinical remission at 4-6 months for patients with moderate-to-severe ulcerative colitis, regardless of prior IS use.