Vedolizumab in the Prophylaxis of Intestinal Acute Graft Versus Host Disease (aGVHD) in Participants Undergoing Allogeneic Hematopoietic Stem Cell (Allo-HSCT) Transplantation

Inclusion Criteria

• •1. Must be \>= 18 years of age and, in selected countries, adolescents aged 12 years and greater and weighing \>=30 kilogram (kg) at time of randomization.
• •2. Must undergo deoxyribose nucleic acid (DNA)-based human leukocyte antigen (HLA) matching and be 8 of 8 or 7 of 8 HLA-matched (singe allele or antigen mismatch at HLA-A, -B, and -C, and HLA-DRB1 is allowable) unrelated hematopoietic stem cell transplantation (HSCT) from either peripheral blood or bone marrow stem cells for a hematologic malignancy or myeloproliferative disorder.
• •3. For whom a myeloablative conditioning or reduced intensity conditioning (RIC) is planned.
• •4. Allo-HSCT eligible (meeting institutional criteria)-participants planned medical care should include aGvHD prophylaxis with a combination of calcineurin inhibitor (CNI) (cyclosporine \[CYS\] or tacrolimus \[TAC\]) and methotrexate (MTX) or CNI and mycophenolate mofetil (MMF). With the exception of antithymocyte globulin (ATG) (antithymocyte globulin-Fresenius \[ATG-F\] or thymoglobulin), all other therapies, approved or investigational, for GvHD prophylaxis are excluded.
• •5. Eastern Cooperative Oncology Group (ECOG) performance status of \<= 2 for participants aged \>=18 years at randomization or \>=60 % using the Karnofsky performance status for adolescent participants aged \>=16 years at randomization or the Lansky performance status for adolescent participants aged 12 to \< 16 years at randomization.