Withdrawal of Etanercept After Successful Treatment of Juvenile Idiopathic Arthritis (ABC-STOP)

• Flare-rate [ Time Frame: 9 months ] [ Designated as safety issue: Yes ]
  To evaluate if the flare-rate is different between the 2 arms (continuation and discontinuation of etanercept).
  
  

• Duration of remission before withdrawal of etanercept [ Time Frame: 9 months ] [ Designated as safety issue: No ]
  To evaluate between the 2 arms (continuation and discontinuation of etanercept) if time in remission on etanercept is an important factor in retaining remission after discontinuation of etanercept.
  
  
• Predictors for successful discontinuation of etanercept [ Time Frame: 12 months after discontinuation of etanercept ] [ Designated as safety issue: No ]
  Evaluation of predictors (patient or disease characteristics, including time in remission, and MRP8/MRP14) for successful discontinuation of etanercept in all JIA patient who discontinue etanercept.
  
  
• Disease course after flaring [ Time Frame: 6 months after flare ] [ Designated as safety issue: No ]
  After a flare (exacerbation) occurs: evaluation of time to flare and the effect of restarting etanercept after flaring.
  
  

Juvenile Idiopathic Arthritis (JIA) is the most common cause of chronic arthritis in children. Etanercept has proven to be an effective treatment for JIA. Considering the risk of occurrence of long-term side-effects and to prevent the burden of the weekly injections and costs, it is a logical step to discontinue etanercept after reaching remission (no disease activity for at least six months). Especially since there are concerns about the long-term effect of suppressing the immune system with etanercept. However, little is known about if successful discontinuation is possible or when to stop. Risk is that the disease might flare (reactivate) again.

For this study, JIA patients in remission will be selected from the ABC-register (an observational study including all Dutch JIA patients who use etanercept). Eligible patients will be randomized to stop etanercept or continue it for another 9 months. Patients are followed with standard visits evaluating disease activity until 12 months after discontinuation of etanercept. In case of a disease flare etanercept therapy will be reintroduced immediately and the patient will be treated according to the insight of their treating physician. Expected is that JIA patients who were in remission for more than 12 months before discontinuation have a better chance to retain remission.