An Observational Study to Assess Change in Disease Activity and Adverse Events of Upadacitinib in Adult Participants With Moderate to Severe Ulcerative Colitis (UC) in Real-World Practice

Ulcerative colitis (UC) is an idiopathic, chronic, inflammatory disease affecting the colon. Participants with UC have mucosal inflammation starting in the rectum that can extend continuously to proximal segments of the colon. This study will assess how safe and effective upadacitinib is in treating adult participants with moderate to severe ulcerative colitis (UC). Adverse events and change in disease activity will be assessed. Upadacitinib is a drug approved for the treatment of Ulcerative colitis (UC). All study participants will receive upadacitinib as prescribed by their study doctor in accordance with approved local label. Approximately 1000 adult participants will be enrolled worldwide. Participants will receive upadacitinib as prescribed by their physician according to their routine clinical practice and local label. Participants will be followed for up to 3 years. There is expected to be no additional burden for participants in this trial. Participants will attend regular visits during the study at a hospital or clinic according to their routine clinical practice.

Inclusion Criteria: * Participants with a diagnosis of moderate to severe Ulcerative colitis (UC). * Participants initiating upadacitinib at the clinician's discretion as part of their routine clinical care; the decision to administer upadacitinib must be made prior to and independent of recruitment into the study. * Participants prescribed upadacitinib in accordance with the approved local label. * Participants able to understand and communicate with the investigator and comply with the requirements of the study. * Participants willing to continue with study documentation after cessation of upadacitinib. * Participants willing and able to participate in the collection of patient-reported data via cloud based mobile application using the provided smart device (iPhone). Exclusion Criteria: * Participants with any contraindication to upadacitinib. * Participants previously exposed to upadacitinib in a clinical trial. * Participants currently participating in interventional research (not including noninterventional study, postmarketing observational study (PMOS), or registry participation).