A Study to Evaluate the Efficacy of Guselkumab in Chinese Participants With Crohn's Disease (CD)

• Guselkumab (GUS) (Drug), also known as TREMFYA: Guselkumab will be administered intravenously or by subcutaneous injection.

Primary outcomes

• Percentage of Participants Achieving Clinical Remission At Week 48 [At Week 48]: Clinical remission is defined as less than (<) 150-point reduction in Crohn's Disease Activity Index (CDAI) score. The CDAI is a validated multi-item measure of severity of illness derived as a weighted sum of 8 different Crohn's disease-related variables. The CDAI score was assessed by collecting information on 8 different Crohn's disease-related variables: extra-intestinal manifestations, abdominal mass, weight, hematocrit, total number of liquid stools, abdominal pain/cramping, use of antidiarrheal drug(s), and/or opiates, and general well-being. In general, CDAI score ranges from 0 to approximately 600; higher score indicates higher disease activities.

Secondary outcomes

• Percentage of Participants Achieving Clinical Response At Weeks 12, 24 and 48 [At Weeks 12, 24 and 48]: Clinical response is defined as greater than or equal to (>=) 100-point reduction from baseline in CDAI score. The CDAI is a validated multi-item measure of severity of illness derived as a weighted sum of 8 different Crohn's disease-related variables. The CDAI score was assessed by collecting information on 8 different Crohn's disease-related variables: extra-intestinal manifestations, abdominal mass, weight, hematocrit, total number of liquid stools, abdominal pain/cramping, use of antidiarrheal drug(s), and/or opiates, and general well-being. In general, CDAI score ranges from 0 to approximately 600; higher score indicates higher disease activities.
• Percentage of Participants Achieving Clinical Remission At Weeks 12 and 24 [At Weeks 12 and 24]: Clinical remission is defined as < 150-point reduction in CDAI score. The CDAI is a validated multi-item measure of severity of illness derived as a weighted sum of 8 different Crohn's disease-related variables. The CDAI score was assessed by collecting information on 8 different Crohn's disease-related variables: extra-intestinal manifestations, abdominal mass, weight, hematocrit, total number of liquid stools, abdominal pain/cramping, use of antidiarrheal drug(s), and/or opiates, and general well-being. In general, CDAI score ranges from 0 to approximately 600; higher score indicates higher disease activities.
• Percentage of Participants Achieving Endoscopic Response [At Weeks 24 and 48]: Endoscopic response is defined as >= 50% improvement from baseline in Simple Endoscopic Score for Crohn's Disease (SES-CD) score. The SES-CD is based on the evaluation of 4 variables: (ulcers - scored according to size, proportion of the surface covered by ulcers according to extent, proportion of affected surface with any other lesions according to extent, stenosis \[single or multiple, and whether the colonoscopy could pass through the narrow lumen\]), each considered in 5 segments of the bowel (the ileum, ascending colon, transverse colon, descending colon, and rectum). An overall total SES-CD score is derived from the sum of all the component scores and can range from 0 to 60. Higher scores indicating severe disease.
• Percentage of Participants Achieving Endoscopic Remission [At Weeks 24 and 48]: Endoscopic remission is defined as SES-CD less than or equal to (<=) 2 in any individual component. The SES-CD is based on the evaluation of 4 variables: (ulcers - scored according to size, proportion of the surface covered by ulcers according to extent, proportion of affected surface with any other lesions according to extent, stenosis \[single or multiple, and whether the colonoscopy could pass through the narrow lumen\]), each considered in 5 segments of the bowel (the ileum, ascending colon, transverse colon, descending colon, and rectum). An overall total SES-CD score is derived from the sum of all the component scores and can range from 0 to 60. Higher scores indicating severe disease.
• Baseline Characteristics of Participants With Endoscopic Remission: Age [Baseline]: Baseline characteristics of participants (age) with endoscopic remission will be reported.
• Baseline Characteristics of Participants With Endoscopic Remission: Sex [Baseline]: Baseline characteristics of participants (sex) with endoscopic remission will be reported.
• Baseline Characteristics of Participants With Endoscopic Remission: Height [Baseline]: Baseline characteristics of participants (height) with endoscopic remission will be reported.
• Baseline Characteristics of Participants With Endoscopic Remission: Weight [Baseline]: Baseline characteristics of participants (weight) with endoscopic remission will be reported.
• Baseline Characteristics of Participants With Endoscopic Remission: History of Advanced Treatment, Concomitant Medications [Baseline]: Baseline characteristics of participants (history of advanced treatment, concomitant medications) with endoscopic remission will be reported.
• Baseline Characteristics of Participants With Endoscopic Remission: Comorbidities [Baseline]: Baseline characteristics of participants (comorbidities) with endoscopic remission will be reported.
• Baseline Characteristics of Participants With Endoscopic Remission: Surgeries and Procedures [Baseline]: Baseline characteristics of participants (surgeries and procedures such as apheresis) with endoscopic remission will be reported.

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Has a confirmed diagnosis of Crohn's disease (CD)
* Diagnosed with active CD, as defined by baseline Crohn's Disease Activity Index (CDAI) score greater than or equal to (>=) 220
* Participants had received the ustekinumab (UST) induction phase and received maintenance therapy via subcutaneous (SC) injection every 8 weeks or every 12 weeks
* Initially responded to UST induction therapy and then lose response to UST
* During the screening period, participants are receiving UST treatment as the first line biologic or second line biologic

Exclusion Criteria:

* Received UST dose optimization or multiple intravenous therapy in maintenance phase
* Participants with CD requiring urgent surgical or endoscopic intervention, or requiring elective surgery within 2 months
* Is currently enrolled in an interventional clinical study
* Complications of CD, such as symptomatic strictures or stenoses, short gut syndrome
* Have a current or be suspected to have an abscess

• Xi'an Janssen Pharmaceutical Clinical Trial, Study director, Xi'an Janssen Pharmaceutical