Treatment for Juvenile Idiopathic Arthritis (UCAN CAN-DU Trial)

Childhood arthritis is a chronic disabling disease. New medications called biologic therapies are now available to treat arthritis that target key biologic molecules that cause inflammation. Biologic therapies, while very effective in treating arthritis in children, may have serious side effects including infections and potentially cancers, and are very expensive and doctors don't know, which one to choose for which child. The investigators will develop tests that enable them to learn about the biology of each child's arthritis and be able to predict when and which biologic therapy to start and when to stop.