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.