Proprotein convertase subtilisin kexin 9 (PCSK9) inhibitors to treat hypercholesterolemia: Effect on stroke risk

A reduction of cardiovascular events has been reported in phase 2 and 3 trials of the proprotein convertase subtilisin kexin 9 (PCSK9) inhibitors alirocumab and evolocumab. We aimed to investigate the effect PCSK9 inhibition on stroke risk in a meta-analysis involving data from randomized studies with alirocumab and evolocumab.

Data from pre-specified combined analysis of 4465 patients who completed phase 2 or 3 studies of evolocumab over a period of 1year and a randomized trial on alirocumab including 2341 patients with hyperlipidemia on maximally tolerated statin who were at high risk for coronary heart disease over a period of 1.5years were used.

The number of patients having an ischemic stroke was small in both trials. PCSK9 inhibition showed no significant effect on stroke rate (risk ratio 1.43; 95% CI, 0.45-4.57, p=0.55). No significant differences in stroke risk were evident when transient ischemic attacks were included in the analysis (risk ratio 0.65; 95% CI, 0.25-1.68, p=0.37). No hemorrhagic strokes were reported in either study.

Although a benefit towards reduction of cardiovascular events in the overall has been documented, longer exposure is warranted to be able to evaluate the effect on stroke risk.