The Efficacy And Safety Of Infliximab In The Treatment Of Ulcerative Colitis: A Meta-analysis

Ulcerative colitis (UC), which is characterized by diarrhea, bloody purulent steal, abdominal pain and tenesmus, is a kind of recurrent disease which can seriously decreases the quality of life of the patients. Up to now, the pathogenesis of UC is still not clear. Genetic, environmental and immune factors play important roles. The over-expressions of inflammatory factors which can induce the tissue damage are believed to be the direct cause of UC. Many studies show that TNF-αexpress abnormally in the patients with UC. At present, most scholars agree that TNF-αplays a significant role in the occurrence of UC. Therefore, inhibition of TNF-αseems to be clinically beneficial in UC.Infliximab is a chimeric monoclonal antibody to recombinant TNF-α, which belongs to the G1 subclass of immune globulin. Its mechanisms of action include neutralization of TNF directly, binding to TNF-α-expressing macrophages and T lymphocytes and then decrease the biological activity of TNF-αand enhance the scavenging activity of those cells through antibody dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC). In clinical, there are more and more trials about infliximab therapy in UC with obviously different results, so it's necessary to make a quantitative comprehensive evaluation on those results to identify the efficacy of infliximab therapy in UC.Objective: To evaluate the efficacy of infliximab quantitatively in the treatment of UC by meta-analysis.Methods: Electronic searches were conducted to identify randomized controlled trials for comparing infliximab versus placebo/steroids in the treatment of UC. Methodological quality of trials was assessed according to Jadad scale. Data extraction and assessment of methodological quality of each study were independently performed by two reviewers. Meta analysis was employed to evaluate the results of the RCTs.Results: Seven randomized controlled trials of infliximab therapy in UC, five of which were compared with placebo, were identified to accordance with the inclusion criteria and were included in this meta-analysis. The meta-analysis results showed that, the odds ratios (ORs) of short-/long-term response/remission with infliximab was 3.95 (95% confidence interval [CI ] 2.85～5.46), 3.93 (95% CI 2.57～6.02), 3.28 (95% CI 2.31～4.65), 3.01 (95% CI 2.01～4.51). Infliximab was also more effective than placebo in promoting mucosal healing (OR=2.92, 95% CI 2.14～3.98) and in reducing the need for colectomy (OR=0.17, 95% CI 0.05～0.54). Adverse effects were a little more common in infliximab versus placebo (OR=1.52, 95% CI 1.05～2.21). Conclusions: In patients with moderate-to-severe active UC who are refractory to conventional treatment, infliximab is effective. Infliximab could induce and maintain a clinical response and clinical remission, and promote mucosal healing of patients with ulcerative colitis. Infusion of infliximab may reduce the need for colectomy in the short term, but the long-term effect on colectomy remains to be confirmed in the future studies. Adverse events attributable to infliximab are a bit more common than placebo, while serious adverse events are rare.