A Protocol of Icotrokinra Therapy in Adult and Adolescent Participants With Moderately to Severely Active Ulcerative Colitis

Inclusion Criteria:

• Diagnosis of ulcerative colitis (UC) established at least 12 weeks before screeningincluding both endoscopic evidence and a histopathology report consistent with adiagnosis of UC

• Moderately to severely active UC, defined as a baseline (Week I-0) modified Mayoscore of 5 to 9, inclusive, using the endoscopy subscore obtained during the centralreview of the screening video endoscopy

• An endoscopy subscore greater than or equal to (>=) 2 as obtained during centralreview of the screening video endoscopy

• Adolescent Participants: body weight must be >= 40 kilograms (kg) at baseline (WeekI-0)

• Adult female participants of childbearing potential and all adolescent femaleparticipants must have a negative highly sensitive serum pregnancy test (beta-humanchorionic gonadotropin [β-hCG]) at screening and a negative urine pregnancy test atWeek I-0 prior to administration of study intervention and agree to furtherpregnancy tests

• Demonstrated an inadequate response to, or failure to tolerate conventional therapybut are naïve to advanced therapies (ADT naïve), or inadequate response to (that is,primary or secondary nonresponse) or failure to tolerate advanced therapy defined asbiologics and/or advanced oral agents for the treatment of UC (ADT-inadequateresponder [IR]) as defined in the protocol

Exclusion Criteria:

• Participants with current known complications of UC such as fulminant colitis, toxicmegacolon, or any other manifestation that might require colonic surgery whileenrolled 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 orother major surgery performed within 12 weeks before baseline

• History of extensive colonic resection (that is, less than [<] 30 centimeter [cm] ofcolon remaining) or colonic resection that could impair the use of disease severityassessments (for example Mayo Score) to assess response to study intervention