Predictors of the response to etanercept in patients with juvenile idiopathic arthritis without systemic manifestations within 12 months: results of an open-label, prospective study conducted at the National Scientific and Practical Center of Children's Health, Russia.

Background: The aim of this study was to investigate the efficacy of etanercept treatment and to identify predictors of response to therapy within 12 months in patients with juvenile idiopathic arthritis (JIA) without systemic manifestations.

Methods: A total of 197 juvenile patients were enrolled in this study. Response to therapy was assessed using the ACRPedi 30/50/70/90 criteria, the Wallace criteria, and the Juvenile Arthritis Disease Activity Score 71 (JADAS-71).