Efficacy and safety of canakinumab in systemic juvenile idiopathic arthritis: 48-week results from an open-label phase III study in Japanese patients.

To assess the efficacy and safety of canakinumab in Japanese patients with systemic juvenile idiopathic arthritis (sJIA). This was an open-label, single-arm active treatment study. sJIA patients, aged ≥2 to <20 years, were administered canakinumab 4 mg/kg every 4 weeks for ≤48 weeks. The co-primary endpoints were the proportion of patients who achieved an adapted American College of Rheumatology pediatric (ACR pedi) 30 criteria at week 8, and the proportion of patients who successfully tapered corticosteroids at week 28. Herein, the efficacy and safety results up to 48 weeks are reported. Of the 19 patients enrolled, 15 (78.9%) had previously used tocilizumab. All patients achieved ACR pedi 30 at week 8 and 73.7% (14/19) successfully tapered corticosteroids at week 28. At week 48, ACR pedi 50/70/90/100 responses were achieved by 100.0%/100.0%/87.5%/68.8% of patients. The most common adverse events (AEs) were infections (271.6 patient-years), 42.1% (8/19) patients had serious AEs. Two potential cases of macrophage activation syndrome were identified. No deaths were reported. Canakinumab was efficacious in Japanese patients with sJIA and was associated with substantial corticosteroid dose reduction in the majority of patients. The safety profile of canakinumab was consistent with that observed from previous studies. NCT02396212).