Effectiveness and safety of subcutaneous abatacept in biologic-naïve RA patients at Week 52: A Japanese multicentre investigational study (ORIGAMI study).

Objectives: To evaluate the effectiveness and safety of abatacept over 52 weeks in biologic-naïve rheumatoid arthritis (RA) patients with moderate disease activity in the prospective, 5-year, observational study (ORIGAMI study) in Japan.

Methods: Abatacept (125 mg) was administered subcutaneously once a week. Clinical outcomes included Simplified Disease Activity Index (SDAI) remission at Week 52 (primary endpoint), Japanese Health Assessment Questionnaire (J-HAQ), EuroQol 5-Dimension Questionnaire (EQ-5D), treatment retention, and safety. The results were compared with those of conventional synthetic disease-modifying antirheumatic drug (csDMARD) controls from the ongoing Institute of Rheumatology, Rheumatoid Arthritis (IORRA) registry.

Results: Overall, 325 patients were enrolled, with a mean age of 66.9 ± 12.7 years. The proportion of patients achieving SDAI remission (≤3.3) at Week 52 was 18.9% (95% CI: 14.3-23.6) and low disease activity (≤11) was 53.3% (95% CI: 47.4-59.1). A significant improvement was observed in J-HAQ and EQ-5D over 52 weeks in both the abatacept and csDMARD groups. The probability of abatacept treatment retention at Week 52 was 69.9% (95% CI: 64.7-75.5). Adverse events and serious adverse events were reported in 50.0% and 12.1% of patients, respectively.

Conclusions: Abatacept significantly improved disease activity, physical disability, and quality of life for up to 52 weeks in RA patients in a real-world setting.