A longterm prospective real-life experience with leflunomide in juvenile idiopathic arthritis.

Objective: To describe a clinical practice with leflunomide (LEF) in juvenile idiopathic arthritis (JIA).

Methods: Patients with JIA seen between May 2008 and May 2012 and considered nonresponsive to methotrexate (MTX) were given LEF and prospectively followed. Primary outcome was a 28-joint Disease Activity Score (DAS28) of low disease activity (< 3.2) in less than 6 months. Childhood Health Assessment Questionnaire (CHAQ) scores and safety data were recorded.

Results: Forty-three patients (33 female) were included with 25 (58.1%) polyarticular, 10 oligoarticular (7 extended; 3 persistent), 6 systemic, and 2 enthesitis-related. Ten (23.2%) were rheumatoid factor-positive and 7 (16.3%) had antinuclear antibodies. Prior drugs other than MTX: 11 (25.5%) chloroquine diphosphate + MTX and 2 (4.6%) sulfasalazine + MTX; mean prednisone dose was 6.4 ± 9.3 mg. The MTX dose prior to LEF was 14.5 ± 4.5 mg/m(2)/week. LEF dose and duration of therapy were 16.6 ± 5.2 mg/d and 3.6 ± 2.2 years, respectively. Nineteen patients (44.2%) interrupted LEF: 1 entered remission, 11 were nonresponsive, and 7 were intolerant (16.2%). Baseline DAS28 (5.57 ± 0.7) dropped to 3.7 ± 1.2 at final analysis (p < 0.001) and 16 patients (37.2%) had a low DAS28 [< 3.2; 12 (27.9%) while taking LEF + MTX and 4 (9.3%) while taking monotherapy]. At last followup, the number of patients with DAS28 > 5.1 dropped from 34 (79%) to 9 (20.9%) and CHAQ scores from 0.86 ± 0.7 to 0.44 ± 0.5 (p < 0.001).

Conclusion: LEF isolated or combined with MTX is effective and safe to treat JIA in patients refractory to MTX.