EFFICACY AND SAFETY OF ETANERCEPT TREATMENT IN PATIENTS WITH JUVENILE IDIOPATHIC ARTHRITIS WITHOUT SYSTEMIC MANIFESTATIONS. THE RESULTS OF AN OPEN PROSPECTIVE STUDY ON THE BASIS OF THE SCIENTIFIC CENTER OF CHILDREN'S HEALTH (MOSCOW)

Background: Addition of genetically engineered biological agents in the paradigm of juvenile idiopathic arthritis (JIA) treatment significantly increased the efficacy of the antirheumatic therapy in patients with this severe chronic disease. Objective. Our aim was to assess the efficacy and safety of etanercept treatment in patients with JIA without systemic manifestations. Methods. The open prospective study included patients with JIA without systemic manifestations treated with etanercept. The treatment was carried out on the basis of the rheumatological department of the Scientific Center of Children's Health (Moscow) in the period from December 2009 to August 2014. To assess the therapy efficacy in a year, we used the improvement definition for pediatric patients of the American College of Rheumatology (ACRpedi) 30, 50, 70, and 90. Reaching the stage of inactive disease/remission were recorded under С. Wallace criteria and threshold value of the JIA activity index (JADAS71). Results. Totally, the study included 197 patients. After 1 year from the treatment beginning, the ACRpedi30 improvement was reported in 179 (90.9%) patients, ACRpedi50 — in 177 (89.8%), ACRpedi70 — in 168 (85.3%), and ACRpedi90 — in 135 (68.5%). The stage of inactive disease/remission under C. Wallace criteria was ascertained in 132 (67.0%), under JADAS71 index — in 92 (46.7%) patients. Conclusion. After 1 year of etanercept treatment, the stage of inactive disease/remission and the improvement under ACRpedi90 criterion have been reported in almost half (45.7%) of patients with juvenile idiopathic arthritis without systemic manifestations. The predictors of a high response to etanercept were a short disease duration, less number of used disease-modifying antirheumatic drugs, and a low level of C-reactive protein in the blood serum before etanercept prescription.