This study is about kids with juvenile spondyloarthritis (a type of arthritis that affects children) who have their disease under control using a medication called TNFi (tumor necrosis factor inhibitor). The study will last for 12 months and will include children aged 8 to 21 years. Patients will be split into three groups: keep taking the same amount of TNFi, take it less often, or stop it completely. Doctors will check on the kids every 3 months to see how they are doing. After the 12-month period, doctors and families can decide together if they want to change the treatment plan. There will be two more years of follow-up to see how the kids are doing long-term.

• Study length: 12 months, with a 24-month follow-up.
• Visits every 3 months during the study.
• No compensation mentioned, but involves de-escalating treatment.