Korea Xeljanz Post-marketing Surveillance for Juvenile Idiopathic Arthritis

This is a post-marketing surveillance study in South Korea to monitor the real-world safety and effectiveness of Xeljanz (tofacitinib) in children with juvenile idiopathic arthritis (JIA) — a chronic inflammatory joint disease that can severely limit movement and quality of life in young patients. Post-marketing surveillance is required after a new medication receives approval to ensure it continues to perform safely when used in everyday clinical practice outside of controlled trials. Participants must be children aged 2 to under 18 years who are receiving Xeljanz as prescribed by their doctor, in line with the approved medication label. A parent or legal guardian must provide signed informed consent. Children who have a contraindication to Xeljanz as per the current approved labelling are excluded. No experimental treatment is given — the study simply collects data from routine clinical care. This research matters because children are not always well-represented in the original drug approval trials, and ongoing safety surveillance ensures that the medication continues to be used safely and effectively in the broadest range of real-world paediatric patients.