Tocilizumab, a monoclonal antibody that targets the interleukin-6 receptor, is approved for the treatment of adult patients with moderately to severely active rheumatoid arthritis (RA) who have had an inadequate response to ≥1 disease-modifying antirheumatic drugs. Although tocilizumab has been known to elevate serum lipid levels in patients with RA, its cardiovascular (CV) effects are unknown. Using 3 US healthcare claims databases, this population-based cohort study compared the CV risk associated with tocilizumab versus abatacept in patients with RA who newly started tocilizumab (n = 6237) or abatacept (n = 14,685).
The primary study outcome was a composite CV end point of hospitalization of any length for myocardial infarction (MI) and stroke based on claims-based algorithms (positive predictive value >94%). Secondary outcomes included the individual end points of MI, stroke, acute coronary syndrome, coronary revascularization, heart failure, and all-cause mortality.
Across the 3 databases (Medicare, n = 1516; MarketScan, n = 9756; PharMetrics, n = 5575), tocilizumab starters experienced a total of 32 CV events, whereas abatacept starters experienced 112 events. In the tocilizumab cohort, the incidence rates of composite CV events per 100 person-years were 0.37 for PharMetrics, 0.42 for MarketScan, and 1.64 for Medicare, for a combined rate of 0.70; and 0.59, 0.68, and 1.69, respectively, in the abatacept cohort, for a combined rate of 0.96. The risk for the primary composite CV events was similar between the 2 treatment groups across all 3 databases, with a combined hazard ratio of 0.82 (95% confidence interval, 0.55-1.22) in tocilizumab initiators versus abatacept initiators. Secondary outcomes of hospitalization for MI, stroke, coronary revascularization, heart failure, and all-cause mortality were also similar between the 2 cohorts.
The researchers concluded that patients with RA who newly started tocilizumab faced no increased risk for CV events versus those who started abatacept.
Source: Kim SC, Solomon DH, Rogers JR, et al. Cardiovascular safety of tocilizumab versus abatacept in patients with rheumatoid arthritis: a multi-database study. Arthritis Rheumatol. 2017;69(suppl 10). Abstract 527.
