A Study of the Efficacy and Safety of Guselkumab in Participants With Moderately to Severely Active Crohn's Disease

This program consists of 3 separate studies: a 48-week Phase 2 dose-ranging study (GALAXI 1)
and two 48-week Phase 3 confirmatory studies (GALAXI 2 and GALAXI 3). In Phase 2, safety and
efficacy of guselkumab dose regimens will be evaluated to support the selection of induction
and maintenance dose regimens for confirmatory evaluation in Phase 3. Participants who
complete the 48-week Phase 2 or Phase 3 studies may be eligible to enter the long term
extension (LTE). Throughout the 3 studies, efficacy, pharmacokinetic, biomarkers, and safety
will be assessed.

Inclusion Criteria:

- Have Crohn's disease (CD) or fistulizing Crohn's disease of at least 3 months duration
(defined as a minimum of 12 weeks), with colitis, ileitis, or ileocolitis, confirmed
at any time in the past by radiography, histology, and/or endoscopy

- Have moderate to severe CD as assessed by CDAI, stool frequency (SF), and abdominal
pain (AP) scores, and Simple Endoscopic Score for Crohn's Disease (SES-CD)

- Have screening laboratory test results within the protocol specified parameters

- A female participant of childbearing potential must have a negative urine pregnancy
test result at screening and baseline

- Demonstrated intolerance or inadequate response to conventional or to biologic therapy
for CD

Exclusion Criteria:

- Current diagnosis of ulcerative colitis or indeterminate colitis

- Has complications of Crohn's disease, such as symptomatic strictures or stenoses,
short gut syndrome, or any other manifestation

- Unstable doses of concomitant Crohn's disease therapy

- Receipt of Crohn's disease approved biologic agents, investigational agents, or
procedures outside of permitted timeframe as specified in the protocol

- Prior exposure to p40 inhibitors or p19 inhibitors

- Any medical contraindications preventing study participation