Long-term safety and effectiveness of adalimumab for the treatment of Japanese patients with rheumatoid arthritis: 3-year results from a postmarketing surveillance of 552 patients

Objectives: To determine the safety and effectiveness of and identify associated factors in long-term adalimumab (ADA) treatment of Japanese patients with rheumatoid arthritis (RA). Methods: Of 7740 patients participating in the all-case postmarketing surveillance study, 552 were enrolled in the present study and observed for 3 years. The safety and effectiveness of ADA were analyzed in 509 and 430 patients, respectively. Results: Adverse drug reactions (ADRs) were reported in 34.2% of patients (23.3/100 person-years [PYs]); serious ADRs (SADRs) were reported in 10.6% (5.9/100 PYs). The most common ADRs and SADRs were infection (16.5%) and serious infection (6.1%), respectively. Seven patients (1.4%) developed malignancies. Multivariate analysis revealed that the risk factors for SADRs were age ≥65 years and respiratory disorder at baseline. The proportion of patients who achieved remission (28-joint count Disease Activity Score based on four erythrocyte sedimentation rates <2.6) increased from 3.3% at baseline to 49.2% at 36 months. Significant predictors of failure to achieve remission were female sex, age ≥65 years, blood disorders and advanced structural change at baseline. Conclusions: Overall, no unknown safety issues were noted during the 3-year treatment with ADA in Japanese patients with RA.