Etanercept treatment in patients with refractory systemic onset juvenile rheumatoid arthritis

. To assess the efficacy and safety of etanercept in a large cohort of children with refractory systemic onset juvenile rheumatoid arthritis (SOJRA).

Standardized questionnaires were sent to US pediatric rheumatologists about patients with SOJRA treated with etanercept. Data were collected at baseline and at the last visit on etanercept. Response to treatment was assessed and compared to baseline as the mean percentage reduction in the following: acute phase reactants, prednisone dose, active joint count, and physician global assessment of disease activity. Response was defined as poor if the mean reduction was < 30%, fair if 30% to < 50%, good if 50% to < 70%, and excellent if > 70%.

We analyzed data obtained by survey of 82 SOJRA patients treated with etanercept for a mean of 25 months. Poor response to treatment was observed in 45% of the children, fair response in 9%, good in 13%, and excellent in 33%. Baseline steroid therapy could be discontinued in 27/59 (46%) patients. One or more disease flares occurred in 45% of all patients. Twenty-nine patients (35%) discontinued therapy, mostly due to lack of response or flare. There were 32 adverse event reports, most not considered serious, except for 2 cases of macrophage activation syndrome.

In this cohort of children with SOJRA, 46% had a good or excellent response, and most were able to reduce concomitant corticosteroid doses. The response to etanercept was fair or poor in more than half our study population, and disease flares were common. Due to the unique cytokine profile of SOJRA, tumor necrosis factor blockade may not be the optimal therapeutic approach for children with treatment-resistant SOJRA.