VERIFY: Vedolizumab for the Prevention of Immune Checkpoint Inhibitor Related Diarrhea or Colitis in Patients With Cancer

Inclusion Criteria: * Signed informed consent prior to initiation of any study specific activities or procedures * Diagnosed with unresectable advanced stage III or metastatic stage IV malignancy * Planned for initiation of SOC immunotherapy and development of prognostic biomarker evidence that predisposes to ICI diarrhea/colitis risk * Ability to and willingness to adhere to the randomized treatment interventions (vedolizumab or placebo), administered intravenously Exclusion Criteria: * Condition(s) for which vedolizumab is contraindicated (e.g., hypersensitivity reaction, known allergic reaction to vedolizumab or its components) * Current or prior use of vedolizumab or prior immunotherapy exposure for cancer * Presence of inflammatory bowel disease (Crohn's disease, ulcerative colitis), indeterminate colitis, or microscopic colitis * Presence of ileostomy, colostomy, or short bowel syndrome * Presence of known luminal gastrointestinal metastases at baseline * Presence of significant pre-existing autoimmune disease (at investigator's discretion) * Presence of severe infection(s) or opportunistic infection(s) * Active enteric infection with viral, bacterial, or parasitic pathogens * Presence of untreated latent or active tuberculosis, or untreated chronic hepatitis B virus * Baseline ECOG status grade ≥3 * Pregnancy or lactation * Treatment with another investigational product within 8 weeks of randomization * Requirement for baseline anti-diarrheal treatment(s) (including…