Real-World Study of IL-23 Inhibitors in Active Crohn's Disease

The goal of this observational study is to learn about the effectiveness and safety of IL-23 inhibitors in adults with active Crohn's disease in real-world clinical practice. The main questions it aims to answer are: * What proportion of participants achieve clinical remission at Week 12 after starting treatment with an IL-23 inhibitor? * What are the clinical, endoscopic, biomarker, imaging, and safety outcomes during induction and maintenance treatment? This is not a head-to-head randomized study. Treatments are selected by treating physicians as part of routine clinical care. For a nested comparative analysis, bio-naive participants treated with IL-23 inhibitors will be compared with a concurrent prospective cohort of bio-naive participants treated with TNF inhibitors to evaluate comparative effectiveness and safety. Participants will: * Receive treatment chosen by their treating physicians as part of routine clinical care, including IL-23 inhibitors or TNF inhibitors * Attend study follow-up visits during induction and maintenance, including assessments at baseline, Week 12 and Week 52 * Undergo routine clinical evaluations, which may include symptom assessment, laboratory tests, endoscopy, and imaging, as available * Be monitored for adverse events and treatment changes during the study * Optionally provide blood, stool, and other available samples for exploratory biomarker, microbiome, metabolomic, and other multi-omics analyses related to treatment response