Tocilizumab and the risk of respiratory adverse events in patients with rheumatoid arthritis: a systematic review and meta-analysis of randomised controlled trials.

Objective. The purpose of this study is to evaluate the relative risk (RR) of respiratory adverse events (AEs) among patients with RA treated with TCZ. Methods. Databases (PubMed, Embase and Cochrane Library) were searched for randomised controlled trials (RCT) comparing the use of TCZ with placebo (PBO) or active comparator agents in adults with RA published until October 28, 2017. Statistical analyses were conducted to calculate the RR of infectious and non-infectious respiratory AEs and severe AEs (SAEs) using random-effects or fixed-effects models based on the heterogeneity of the included studies. Results. Eight trials were ultimately included. TCZ was associated with an increased risk of infectious respiratory AEs relative to comparator agents (RR 1.53, 95% confidence interval [95% CI] 1.04-2.25) but was not associated with an increased risk of non-infectious respiratory AEs (RR 1.19, 95% CI 0.86-1.64). A subgroup analysis revealed similar results for non-infectious AEs and SAEs in the comparisons of TCZ with MTX and adalimumab (ADA), whereas increased risks of these AEs but not SAEs were observed compared with the PBO. Conclusions. Our meta-analysis did not reveal an increase in the risk of non-infectious respiratory AEs in adult patients with RA who were treated with TCZ compared with other csDMARDs and bDMARDs in RCTs.