Pfizer
The purpose of this study is to determine the safety, efficacy, and pharmacokinetics (PK) of etrasimod for the treatment of moderately to severely active ulcerative colitis in adolescents (≥ 12 years up to \< 18 years of age). Participants who will complete the total 52-week treatment period will have the opportunity to continue in a Long-Term Extension (LTE) Period of up to 4 years (5 years after study enrollment).
Inclusion criteria: * Have a diagnosis of ulcerative colitis (UC) that is moderately to severely active * Participants are permitted to be receiving a therapeutic dose of select UC therapies Exclusion criteria: * Severe extensive colitis * Diagnosis of Crohn's disease (CD) or indeterminate colitis or the presence or history of a fistula consistent with CD * Diagnosis of microscopic colitis, ischemic colitis, or infectious colitis
Etrasimod tablet or granules by mouth, once daily up to 52 weeks of treatment.