Vedolizumab [Entyvio(®) (US, Europe)], a humanized monoclonal antibody α4β7 
integrin receptor antagonist, has been developed by Millennium Pharmaceuticals 
(d/b/a Takeda Pharmaceuticals International) for the treatment of ulcerative 
colitis and Crohn's disease. Vedolizumab has received its first global approval 
for the treatment of ulcerative colitis and Crohn's disease in the US, for use 
in adult patients with moderate-to-severe disease who have had an inadequate 
response, loss of response or intolerance to one or more standard therapies 
(corticosteroids, immunomodulators or tumour necrosis factor-α inhibitor) or 
demonstrated dependence on corticosteroids. Vedolizumab has since been approved 
for ulcerative colitis and Crohn's disease in the EU, Norway, Iceland and 
Liechtenstein. This article summarizes the milestones in the development of 
vedolizumab leading to its first approval for the treatment of ulcerative 
colitis and Crohn's disease.