Increased Risk of Adverse Neurocognitive Outcomes With Proprotein Convertase Subtilisin-Kexin Type 9 Inhibitors

Abstract

Background— There is encouraging evidence of the efficacy of proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitors; however, their long-term safety remains unclear. We performed a meta-analysis of studies to evaluate the long-term safety of PCSK9 inhibitors. Methods and Results— Our search strategy yielded 11 studies (9 smaller early-phase and 2 larger outcome trials). The outcomes assessed were cumulative serious adverse events, musculoskeletal adverse events, neurocognitive adverse events, and stroke. Odds ratio (OR) was calculated using the Mantel–Haenszel method. Subgroup analysis was done to assess the difference in safety between the smaller early-phase studies and the larger outcome studies. Our meta-analysis suggested no difference in the incidence of serious adverse events (OR, 1.00; 95% confidence interval [CI], 0.88−1.15), musculoskeletal adverse events (OR, 1.01; 95% CI, 0.87−1.13), neurocognitive adverse events (OR, 1.29; 95% CI, 0.64−2.59), or stroke (OR, 1.44; 95% CI, 0.57−3.65) with the use of PCSK9 inhibitors. Subgroup analysis of the 2 large outcome studies did suggest an increased incidence of neurocognitive adverse events (OR, 2.85; 95% CI, 1.34−6.06) with the use of PCSK9 inhibitors. However, the overall incidence of neurocognitive adverse events and stroke was <1%, whereas the cumulative incidence of serious adverse events and musculoskeletal events was >10% in both the groups. Conclusions— Our analysis suggests that PCSK9 inhibitors are not associated with an increased risk of cumulative severe adverse effects, musculoskeletal effects, or stroke. There is a signal toward adverse neurocognitive effects, seen in the outcome studies with a larger sample size and longer follow-up. There should be close monitoring, for the increased risk of neurocognitive events in the ongoing outcome studies and post-marketing surveillance.