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

* Male or female aged \>=18 to \<= 80 years, or minimum age of adult consent according to local regulations, at the Baseline Visit. Where locally permissible, participants 16 to \< 18 years of age who meet the definition of Tanner stage 5 for development at the Baseline Visit. * Diagnosis of CD for at least 3 months prior to Baseline. * Confirmed diagnosis of moderate to severe CD as assessed by stool frequency (SF), abdominal pain (AP) score, and Simple Endoscopic Score for Crohn's Disease (SES-CD). * Demonstrated intolerance or inadequate response to conventional or to biologic therapy for CD. * If female, participant must meet the contraception recommendations.

* Participant with a current diagnosis of ulcerative colitis or indeterminate colitis. * Participants with unstable doses of concomitant Crohn's disease therapy. * Receipt of Crohn's disease approved biologic agents (infliximab, adalimumab, certolizumab, vedolizumab, natalizumab within 8 weeks prior to Baseline or ustekinumab within 12 weeks prior to Baseline), or any investigational biologic or other agent or procedure within 35 days or 5 half-lives prior to Baseline, whichever is longer. * Prior exposure to p19 inhibitors (e.g., risankizumab). * Complications of Crohn's disease. * Having an ostomy or ileoanal pouch. * Known active Coronavirus Disease 2019 (COVID-19) infection.