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.