A Study of Vedolizumab Intravenous (IV) and Adalimumab or Vedolizumab and Ustekinumab in Adults With Crohn's Disease

Inclusion Criteria:

Part A:

1. Has a confirmed diagnosis of CD at least 3 months before screening, based onendoscopy results.

2. Has moderately to severely active CD at Screening, defined as an SES-CD >=6 (>=4 ifisolated ileal disease).

3. Has demonstrated at least 1 of the following (a, b, or c) to at least 1 ILantagonist or at least 1 tumor necrosis factor (TNF) antagonist, at doses approvedfor the treatment of CD:

4. Inadequate response after completing the full induction regimen;

5. Loss of response (recurrence of symptoms during scheduled maintenance dosingafter prior clinical benefit); or

6. Intolerance (a significant adverse event that precluded further use, includingbut not limited to serious infection including opportunistic infections,malignancy, infusion-related and hypersensitivity reactions includinganaphylaxis, and liver injury). Note: Participants with an inadequate response to >2 classes of advanced therapiesor >1 agent in the same class are not eligible. Participants who discontinued athird class of advanced therapy for reasons other than inadequate response may beeligible after discussion with the Medical Monitor. Part B:

7. In the investigator's opinion, the participant exhibits a therapeutic benefit atWeek 26.

Exclusion Criteria:

1. CDAI score > 450.

2. A current diagnosis of ulcerative colitis or indeterminate colitis.

3. Clinical evidence of an abdominal abscess.

4. Known fistula (other than perianal fistula) or phlegmon.

5. Known perianal fistula with abscess.

6. Ileostomy, colostomy, or severe, or symptomatic stenosis of the intestine.

7. Previous extensive bowel resection with 2 entire segments missing, of the following:terminal ileum, right colon, transverse colon, sigmoid and left colon, and rectum.

8. Short bowel syndrome.

9. Any planned surgical intervention for CD, except for seton placement for perianalfistula without abscess.

10. History or evidence of adenomatous colonic polyps that have not been removed.

11. History or evidence of colonic mucosal dysplasia.

12. Intolerance or contraindication to ileocolonoscopy.

13. Any identified congenital or acquired immunodeficiency (eg, common variableimmunodeficiency infection).

14. Active or latent tuberculosis (TB), regardless of treatment history.

15. A positive test for hepatitis B virus (HBV) as defined by the presence of hepatitisB surface antigen (HBsAg) or hepatitis B core antibody (HBcAb) test.

16. A positive test for hepatitis C virus (HCV), as defined by a positive hepatitis Cvirus antibody (HCVAb) test and detectable HCV ribonucleic acid (RNA).

17. Received approved or investigational anti-integrin antibodies (i.e., vedolizumab,natalizumab, efalizumab, etrolizumab, abrilumab [AMG 181], anti- mucosal addressincell adhesion molecule-1 [MAdCAM-1] antibodies, or rituximab) for the treatment ofCD.

18. History of or symptoms of progressive multifocal leukoencephalopathy (PML) in theinvestigator's opinion. If a participant has symptoms consistent with PML, a PMLchecklist must be completed and submitted to the PML independent adjudicationcommittee. If the PML IAC deems the participant to have PML, the participant isineligible.