Postmarketing surveillance of tocilizumab for rheumatoid arthritis in Japan: interim analysis of 3881 patients

Objective An interim analysis of an all-patient postmarketing surveillance programme in Japan to investigate the safety of tocilizumab for the treatment of rheumatoid arthritis (RA) in the real world. Methods This analysis included 3881 patients. Patients received 8 mg/kg of tocilizumab every 4 weeks, and were observed for 28 weeks. Data on baseline characteristics and adverse events (AE) were collected. Results Total and serious AE were reported as 167 and 27 events/100 patient-years, respectively. The most frequent AE and serious AE were infections. Logistic regression analysis identified the following risk factors for the development of serious infection: concurrent or medical history of respiratory disorders; prednisolone dose at baseline ≥5 mg/day; and age ≥65 years. Twenty-five patients died, and the standardised mortality ratio, with the Japanese general population in 2008 as reference, was 1.66, similar to the results from the Japanese cohort study for RA patients. Conclusions Tocilizumab is acceptably safe in the real clinical setting. Tocilizumab needs to be used with consideration of the benefit–risk balance to avoid serious infections in elderly patients and those on high doses of corticosteroids or with a concurrent or medical history of respiratory disorders.