The drug being tested in this study is called vedolizumab. This study will look at the tolerability and effectiveness of vedolizumab IV in participants with acute intestinal GvHD who have received no systemic therapy for the treatment of acute GvHD (prophylaxis acceptable) other than corticosteroids.
The study enrolled 17 participants. Participants will be randomly assigned (by chance, like flipping a coin) to one of the two treatment groups:
* Vedolizumab 300 mg
* Vedolizumab 600 mg
All participants will be infused intravenously at the same time each day throughout the study. Vedolizumab IV will be administered on Days 1, 15, 43, 71, and 99. After approximately 10 participants are enrolled at each dose level and have data available from the Day 28 evaluation, safety, tolerability, efficacy, and pharmacokinetic (PK), results will be assessed for each dose level, and the appropriate dose for subsequent participants in the study will be determined.
This multi-center trial will be conducted in multiple countries. The overall time to participate in this study is 32 weeks. Participants will make multiple visits to the clinic after last dose of study drug for a follow-up assessment.
