The purpose of this protocol is to evaluate the efficacy (how well it works), safety and tolerability of oral icotrokinra as therapy in adult and adolescent participants with moderately to severely active ulcerative colitis (UC, a chronic disease of the large intestine in which the lining of the colon becomes inflamed and develops tiny open ulcers).
Diagnosis of ulcerative colitis (UC) established at least 12 weeks before screening including both endoscopic evidence and a histopathology report consistent with a diagnosis of UC
Moderately to severely active UC, defined as a baseline (Week I-0) modified Mayo score of 5 to 9, inclusive, using the endoscopy subscore obtained during the central review of the screening video endoscopy
An endoscopy subscore greater than or equal to (>=) 2 as obtained during central review of the screening video endoscopy
Adolescent Participants: body weight must be >= 40 kilograms (kg) at baseline (Week I-0)
Participants with current known complications of UC such as fulminant colitis, toxic megacolon, or any other manifestation that might require colonic surgery while enrolled in the study
Presence of a stoma
Presence or history of a fistula
Colonic resection within 24 weeks before baseline or any other intra-abdominal or other major surgery performed within 12 weeks before baseline
6
Treatment groupsSee each treatment group below.