A Master Protocol (IIBD): A Study of Multiple Drugs in Adults With Ulcerative Colitis or Crohn's Disease

Inclusion Criteria: * Must have an established diagnosis of Ulcerative Colitis (UC) or Crohn's Disease (CD) for at least 3 month duration, which includes clinical and endoscopic evidence of UC or CD and a histopathology report that supports a diagnosis of UC or CD. * For UC: * Have moderately to severely active UC as defined by a modified Mayo score (mMS) of 5-9 points and Endoscopic Subscore (ES) greater than or equal to (≥) 2, confirmed by the central reader and rectal bleeding (RB)≥1, with endoscopy performed within 21 days prior to Visit 2. * For CD: * Have moderately to severely active CD as defined by a Crohn's disease activity index (CDAI) score ≥ 220 and less than or equal to (≤) 450. Have a centrally read Simple Endoscopic Score for Crohn's Disease (SES-CD) score ≥6 for participants with ileal-colonic or ≥4 for participants with isolated ileal disease within 21 days before the randomization * Must have demonstrated an inadequate response, loss of response, or intolerance to at least one of the following: corticosteroids, immunomodulators, or an advanced therapy for UC or CD * Have screening laboratory test results within the protocol specified parameters. Exclusion Criteria: * Must not have a current diagnosis of inflammatory bowel disease (IBD)-unclassified or primary sclerosing cholangitis * For UC - must not have a current diagnosis of CD * For CD - must not have a current diagnosis of UC * Must not have had or will need bowel resection or intestinal or intra-abdominal surgery as specified in the protocol * Must not have complications of UC or CD, including but not limited to stricture or stenosis (some exceptions allowed for CD) or short bowel syndrome * Must not have a significant uncontrolled illness that in the opinion of the investigator may compromise the participant's safety or interfere with interpretation of data * Must not have failed more than 5 approved advanced treatments for UC or CD with different mechanisms of action * Must not have failed an anti-interleukin-23p19 (anti-IL-23p19) antibody treatment * Must not have received or will need any prohibited medications for UC or CD as specified in the protocol