Efficacy of Biological Therapies in Inflammatory Bowel Disease: Systematic Review and Meta-Analysis

OBJECTIVES: Crohn's disease (CD) and ulcerative colitis (UC) are inflammatory disorders of the gastrointestinal tract of unknown etiology. Evidence for treatment of the condition with biological therapies exists, but no systematic review and meta-analysis has examined this issue in its entirety. METHODS: MEDLINE, EMBASE, and the Cochrane central register of controlled trials were searched (through to December 2010). Trials recruiting adults with active or quiescent CD or UC and comparing biological therapies (anti-tumor necrosis factor-alpha (TNF alpha) antibodies or natalizumab) with placebo were eligible. Dichotomous symptom data were pooled to obtain relative risk (RR) of failure to achieve remission in active disease and RR of relapse of activity in quiescent disease once remission had occurred, with a 95% confidence interval (CI). RESULTS: The search strategy identified 3,061 citations, 27 of which were eligible. Anti-TNF alpha antibodies and natalizumab were both superior to placebo in inducing remission of luminal CD (RR of no remission = 0.87; 95 % CI 0.80-0.94 and RR = 0.88; 95 % CI 0.83-0.94, respectively). Anti-TNF alpha antibodies were also superior to placebo in preventing relapse of luminal CD (RR of relapse = 0.71; 95 % CI 0.65-0.76). Infliximab was superior to placebo in inducing remission of moderate to severely active UC (RR = 0.72; 95 % CI 0.57-0.91). CONCLUSIONS: Biological therapies were superior to placebo in inducing remission of active CD and UC, and in preventing relapse of quiescent CD.