Long-Term Maintenance of Clinical Responses by Individual Patients With Polyarticular-Course Juvenile Idiopathic Arthritis Treated With Abatacept

Objective: To investigate the frequency and trajectories of individual patients with polyarticular-course juvenile idiopathic arthritis (JIA) achieving novel composite end points on abatacept. Methods: Data from a clinical trial of subcutaneous abatacept (NCT01844518) and a post hoc analysis of intravenous abatacept (NCT00095173) in patients with polyarticular-course JIA were included. Three end points were defined and evaluated: combined occurrence of low disease activity (LDA) measured by the Juvenile Arthritis Disease Activity Score; 50% improvement in American College of Rheumatology criteria for JIA (ACR50); and patient-reported outcomes. Patient-reported outcomes included visual analog scale score of minimal pain (pain-min) and Childhood Health Assessment Questionnaire disability index score of 0 (C-HAQ DI0). In this post hoc analysis, maintenance of month 13 and 21 end points (LDA+pain-min, LDA+C-HAQ DI0, and ACR50+pain-min) in those who achieved them at month 4 was determined. Results: Composite end points (LDA+pain-min, LDA+C-HAQ DI0, and ACR50+pain-min) were achieved at month 4 (44.7%, 19.6%, and 58.9% of the 219 patients treated with subcutaneous abatacept, respectively). Of those who achieved LDA+pain-min at month 4, 84.7% (83 of 98) and 65.3% (64 of 98) maintained LDA+pain-min at months 13 and 21, respectively. The proportions of patients meeting LDA+pain-min outcomes increased from 44.7% (98 of 219) at month 4 to 54.8% (120 of 219) at month 21. The frequency of patients who met an LDA+C-HAQ DI score of 0 increased from 19.6% (43 of 219) at month 4 to 28.8% (63 of 219) at month 21. Conclusion: Among individual patients with polyarticular-course JIA treated with abatacept who achieved 1 of the combined clinical and patient-reported outcomes composite end points, many maintained them over 21 months of abatacept treatment.