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

BackgroundThe benefit of the combination of infliximab (IFX) and immunosuppressant (IS) therapy is debated in ulcerative colitis (UC). AimsTo determine whether the combination of IFX and IS therapy is more effective than infliximab alone for active UC regardless of prior IS use. MethodsWe 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 4-6months. Two statistical methods were used, Mantel-Haenszel and Der-Simonian and Laird. Inter-trial heterogeneity was taken into account and publication bias was assessed. ResultsFour 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 4-6months' 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 12months 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). ConclusionCombination therapy with IFX-IS is more effective than IFX alone for achieving and maintaining clinical remission at 4-6months for patients with moderate-to-severe ulcerative colitis, regardless of prior IS use.