Long-term safety and effectiveness of abatacept in Japanese patients with rheumatoid arthritis: 3-year follow-up of a postmarketing surveillance

Objectives To analyse the long-term safety and effectiveness of abatacept for rheumatoid arthritis using real-world, Japanese, postmarketing surveillance data, focusing on serious infections and malignancies as priority events. Methods This 3-year, multicentre surveillance registered patients undergoing abatacept treatment by intravenous infusion between July 2011 and October 2012. Results The safety and effectiveness analysis sets included 647 and 596 patients, respectively. The total observation period for the safety analysis was 1280 patient-years. Over the 3-year follow-up, the incidence rates of adverse drug reactions (ADRs) and serious ADRs were 19.92 per 100 patient-years (22.87% of patients) and 4.06 per 100 patient-years (6.65% of patients), respectively. Infections and infestations were the most common ADRs (14.68%), followed by respiratory, thoracic, and mediastinal disorders (3.09%). Incidence rates of serious infections as ADRs and malignancy as adverse events were 1.95 and 1.02 per 100 patient-years, respectively. Retention rates at 1 and 3 years were 67.4% and 43.9%, respectively. Significant decreases from baseline were observed in Disease Activity Score (DAS) 28-erythrocyte sedimentation rate and DAS28-C-reactive protein, as well as Health Assessment Questionnaire-Disability Index (HAQ-DI) and modified HAQ scores. Conclusions No new safety signals were detected during the 3-year observation period and effectiveness was maintained over time.