No adverse cognitive effects with evolocumab added to statins in EBBINGHAUS trial
Adding the proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor evolocumab to statin therapy to further lower bad cholesterol does not cause memory loss or other cognitive issues in patients with known cardiovascular disease (CVD), the EBBINGHAUS trial has shown, giving clinicians some sense of reassurance.
There were no significant differences between patients receiving evolocumab and placebo on any of the four measures of cognitive functioning (spatial working memory index of executive function, spatial working memory between errors, paired associates learning, and reaction time), patient questionnaires, or physician-reported adverse cognitive events. Cognitive function was also similar among patients who achieved very low LDL-C levels (<25mg/dL) and those with higher LDL-C values (≥40mg/dL). [ACC.2017, abstract 17-LB-16161-AC]
“The findings make physicians feel more secure about adding evolocumab to statin therapy to achieve very low LDL-C levels without worrying about patients’ cognitive functioning being affected,” said lead investigator Dr Robert P. Giugliano from the Brigham and Women’s Hospital in Boston, US, who presented the findings.
There had been some potential signals for adverse cognitive effects with statins in previous trials, prompting the US Food and Drug Administration to include a safety alert to statin labeling in 2012. However, analyses from large-scale randomized controlled trials (RCTs) do not support these findings. In 2014, the Statin Cognitive Safety Task Force concluded that statins are not associated with cognitive side effects. [J Clin Lipidol 2014 May-Jun;8(3 Suppl):S5-16]
The current data from the EBBINGHAUS trial reinforced the Task Force’s findings.
EBBINGHAUS was a cognitive study of 1,974 patients with atherosclerotic CVD enrolled in the FOURIER Outcomes trial. FOURIER has shown that aside from significantly lowering LDL-C, evolocumab injections (140 mg every other week or 420 mg monthly) on top of statins reduced the risk for the composite primary endpoint of MI, stroke, hospitalization for unstable angina or coronary revascularization, and CV death at 22 months vs placebo (p<0.001). In addition, there was a 20-percent reduction in the risk for the key secondary endpoint of MI, stroke, or CV death with evolocumab (p<0.001). [N Engl J Med 2017; doi:10.1056/NEJMoa1615664]
For EBBINGHAUS, the primary endpoint was a change from baseline on the spatial working memory strategy index (SWMsi) of executive function. Secondary endpoints included working memory, memory function, and psychomotor speed, assessed using an electronic tablet. Mean duration of follow-up was 19.8 months.
Raw scores on the SWMsi did not differ between evolocumab and placebo at baseline (17.8 for each) or at study end (17.5 vs 17.6, respectively). “The treatment differences were well below the upper bounds of the noninferiority boundary,” said Giugliano.
Evidence from EBBINGHAUS and FOURIER trials suggests that in a secondary-prevention population (average age 63) with atherosclerotic CVD, lowering LDL-C below the current targets with evolocumab and a statin does not adversely affect cognitive function and may help improve cardiovascular outcomes
Whether these benefits persist beyond 2 years is the subject of an ongoing long-term follow-up in a subset of patients in the EBBINGHAUS trial.