Safety and Effectiveness of Vedolizumab in Patients with Moderate-to-Severe Ulcerative Colitis: An Interim Analysis of a Japanese Post-Marketing Surveillance Study

Introduction This ongoing post-marketing surveillance monitors the long-term safety and effectiveness of vedolizumab in routine clinical practice in patients with moderate-to-severe ulcerative colitis (UC) in Japan. This interim analysis assessed induction-phase data, covering the initial three doses of vedolizumab.Methods Patients were enrolled via a web-based electronic data capture system from approximately 250 institutions. Incidence of adverse events and treatment responses were assessed by the physicians after the patient had received three doses of vedolizumab or when the drug was discontinued, whichever occurred first. Therapeutic response was defined as any treatment response, including remission or improvement of complete or partial Mayo score, and was assessed in the total and stratified patient populations according to prior tumor necrosis factor alpha (TNFa) inhibitor treatments and/or baseline partial Mayo score.Results The total incidence of adverse drug reactions (ADRs) was 4.10% (11/268). Common ADRs were dizziness, nausea, and arthralgia, each reported in 0.75% of patients (2/268). Serious ADRs were herpes zoster oticus and UC, each reported in 0.37% of patients (1/268). Therapeutic response was reported in 84.5% (218/258) of all patients, 85.8% (127/148) of TNFa inhibitor-naive patients, and 82.7% (91/110) of TNFa inhibitor-experienced patients. Among patients with partial Mayo score of >= 4 at baseline, partial Mayo score remission in patients without or with prior TNFa inhibitor treatment was 62.5% (60/96) and 45.6% (36/79), respectively.Conclusion The results confirm a safety and effectiveness profile of vedolizumab consistent with that observed in previous trials.