Influence of concomitant methotrexate use on the clinical effectiveness, retention, and safety of abatacept in biologic-naïve patients with rheumatoid arthritis: Post-hoc subgroup analysis of the ORIGAMI study.

Objectives: We performed post-hoc analyses of the ORIGAMI study to investigate whether concomitant methotrexate (MTX) influences the clinical outcomes of abatacept in biologic-naïve patients with rheumatoid arthritis.
Methods: Enrolled patients (n = 325) were divided into two groups according to whether abatacept was prescribed without (MTX-) or with (MTX+) concomitant MTX. We compared the changes in Simplified Disease Activity Index (SDAI), Disease Activity Score-28 with C-reactive protein (DAS28-CRP), and Japanese Health Assessment Questionnaire (J-HAQ) through to 52 weeks of treatment, the abatacept retention rate, and safety.
Results: At Week 52, the mean SDAI (8.9 vs. 8.8), DAS28-CRP (2.6 vs. 2.6), and J-HAQ (0.92 vs. 0.91) scores were comparable in the MTX- (n = 129) and MTX+ (n = 150) groups. Multivariable logistic regression revealed no significant association between MTX use and SDAI (low disease activity) or J-HAQ (minimum clinically important difference). The abatacept retention rates, estimated using the Kaplan-Meier method, were 73.2% and 66.7% in the MTX- and MTX+ groups, respectively. Adverse events occurred in 47.5% (of 139) and 52.2% (of 159) of patients in the MTX- and MTX+ groups, respectively.
Conclusion: The effectiveness and safety of abatacept appeared comparable with or without concomitant MTX in this real-world clinical setting.
(© Japan College of Rheumatology 2022. Published by Oxford University Press.)