A Study of Ustekinumab (STELARA) in Chinese Participants With Moderately to Severely Active Crohn's Disease

Prior treatment

• Has complications of Crohn's disease such as symptomatic strictures or stenoses, short gut syndrome, or any other manifestation that might be anticipated to require surgery, could preclude the use of the CDAI to assess response to therapy, or would possibly confound the ability to assess the effect of treatment with ustekinumab
• Has previously demonstrated lack of initial response (that is, primary nonresponders), responded initially but then lost response with continued therapy (that is, secondary nonresponders) to Vedolizumab

Other illness

• Has a history of, or ongoing, chronic or recurrent infectious disease, including but not limited to, chronic renal infection, chronic chest infection (example, bronchiectasis), recurrent urinary tract infection (example, recurrent pyelonephritis or chronic non-remitting cystitis), or open, draining, or infected skin wounds or ulcers
• History of lymphoproliferative disease, including lymphoma, or signs and symptoms suggestive of possible lymphoproliferative disease, such as lymphadenopathy or splenomegaly or monoclonal gammopathy of undetermined significance
• Has a history of severe, progressive, or uncontrolled renal, genitourinary, hepatic, hematologic, endocrine, cardiac, vascular, pulmonary, rheumatologic, neurologic, psychiatric, or metabolic disturbances, or signs and symptoms thereof

• Have Crohn's disease (CD) or fistulizing Crohn's disease of at least 3 months duration, with colitis, ileitis, or ileocolitis, confirmed in the past by radiography, histology, and/or endoscopy
• Have moderately to severely active CD, defined as a baseline Crohn's disease activity index (CDAI) score of greater than or equal to (\>=) 220 and less than or equal to (\<=) 450, and either: a. Mean daily stool frequency (SF) count \>3, based on the unweighted CDAI component of the number of liquid or very soft stools or b. Mean daily abdominal pain (AP) score \>1, based on the unweighted CDAI component of AP
• Have endoscopic evidence of active ileocolonic CD as assessed by central endoscopy reading at the screening endoscopy, defined as a screening simple endoscopic score for crohn's disease (SES-CD) score \>=6 (or \>=4 for participants with isolated ileal disease), based on the presence of ulceration in at least 1 of the 5 ileocolonic segments, resulting in the following specified ulceration component scores: a. a minimum score of 1 for the component of "size of ulcers"; and b. a minimum score of 1 for the component of "ulcerated surface"
• A woman of childbearing potential must have a negative highly sensitive serum (beta-human chorionic gonadotropin \[beta-hCG\]) at screening and a negative urine pregnancy test at baseline
• Must sign an informed consent form (ICF) indicating that he or she understands the purpose of, and procedures required for, the study and is willing to participate in the study