Vedolizumab (Entyvio™) is a humanized monoclonal antibody α4β7 integrin-receptor 
antagonist indicated for the treatment of adult patients with moderately to 
severely active ulcerative colitis or Crohn's disease. This article reviews the 
pharmacological properties of intravenous infusions of vedolizumab and its 
clinical efficacy in adult patients with these diseases. In phase III clinical 
trials, patients with ulcerative colitis had significantly higher rates of 
clinical response and clinical remission when treated with vedolizumab than when 
receiving placebo at both 6 and 52 weeks. However, outcomes with vedolizumab in 
patients with Crohn's disease were mixed. In a study that evaluated both 
clinical remission rate and CDAI-100 response rate as primary endpoints, only 
the clinical remission rate at 6 weeks was significantly higher with vedolizumab 
than placebo. In another trial, there was no significant between-group 
difference in the clinical remission rate in TNF-antagonist failure patients at 
6 weeks (primary endpoint), although there was a significant difference at 
10 weeks. In the Crohn's disease study that included maintenance treatment, 
vedolizumab was significantly more effective at 52 weeks than placebo in both 
endpoints (clinical remission was the only primary endpoint in the maintenance 
study). Vedolizumab was generally well tolerated in these trials. As vedolizumab 
is a specific α4β7 integrin antagonist, with gut-specific effects, it is 
unlikely to be associated with the development of progressive multifocal 
leukoencephalopathy, a risk observed with the less selective α4β7/α4β1 integrin 
antagonist natalizumab. Vedolizumab is a useful addition to the treatment 
options available for patients with moderately to severely active ulcerative 
colitis and Crohn's disease.