Safety and Efficacy of Etanercept in a Cohort of Patients with Juvenile Idiopathic Arthritis Under 4 Years of Age

Objective. To evaluate safety, tolerability, and efficacy of etanercept in a cohort of patients with juvenile idiopathic arthritis (JIA) under 4 years of age. Methods. Data were collected at every visit during treatment with etanercept in 25 children who began treatment at a mean age of 3 years (range 18-48 months). Safety endpoints included the incidence of any adverse events. Efficacy endpoints included the American College of Rheumatology (ACR) Pediatric 30, 50, and 70 criteria for improvement. Results. Data from 25 patients with JIA treated with etanercept for a mean period of 23 months were analyzed. All patients received concomitant medications: 24 methotrexate, 3 cyclosporin A, and 10 corticosteroids. After the first 6 months of treatment, 15 (71.4%) patients achieved an ACR Pedi30 response and at the last observation 20 (80%) achieved ACR Pedi30. ACR Pedi50 and 70 responses were, respectively, 62% and 43% at 6 months and 72% and 64% at the last followup. Five patients (20%) discontinued etanercept for lack of efficacy. Two (8%) developed adverse events, both primary varicella zoster virus (VZV) infections (both not vaccinated). One was hospitalized because of a necrotizing fasciitis secondary to VZV infection. No cases of tuberculosis, opportunistic infections, or malignancies were reported. Conclusion. In our cohort of patients etanercept proved to be safe and efficacious in the majority of children. The response in toddlers was similar to that in older children. We observed only 1 case of severe infection that required hospitalization and stopped treatment temporarily. (J Rheumatol First Release May 152012; J Rheumatol 2012;39:1287-90; doi:10.3899/jrheum.111555)