Safety and effectiveness of subcutaneous tocilizumab in patients with rheumatoid arthritis in a real-world clinical setting

Objectives: The objective of this study is to evaluate the safety and effectiveness of subcutaneous tocilizumab (TCZ-SC) in a real-world clinical setting in Japan. Methods: This single arm, 26-week prospective observational study enrolled patients with RA who were either TCZ naïve or switched from TCZ-IV to TCZ-SC (TCZ-IV-SC group) (UMIN Clinical Trials Registry UMIN000011102). All patients received TCZ-SC 162 mg every 2 weeks and data were collected until week 26 or discontinuation. Results: Overall 784 (78.1%) were TCZ naïve and 219 (21.8%) were in the TCZ-IV-SC group. 70.9% received disease-modifying antirheumatic drugs at baseline. Adverse events (AEs) and serious AEs occurred in 28.2% and 4.9% of patients, respectively (TCZ-naïve: 29.5% and 5.2%; TCZ-IV-SC: 23.2% and 4.1%). Infections and infestations were the most common AEs (7.4%) and serious AEs (1.7%). Two TCZ-naïve patients died. TCZ-naïve patients had an improvement in median Clinical Disease Activity Index (CDAI) score and mean Disease Activity Score in 28 joints as measured by erythrocyte sedimentation rate (DAS28-ESR) from baseline to week 26. The TCZ-IV-SC group had similar median CDAI scores and mean DAS28-ESR over 26 weeks. Conclusions: There were no unexpected safety signals with TCZ-SC. TCZ-SC was effective in reducing disease activity in TCZ-naïve patients and maintaining remission in TCZ-IV-SC patients.