Abstract 14714: Long-Term Neurocognitive Safety of LDL-C Lowering With Evolocumab: Open-Label Extension Data From FOURIER

Background: Concerns have been raised about low LDL-C levels and possible adverse effects on cognition. PCSK9 inhibitors markedly lower LDL-C, yet EBBINGHAUS, a prespecified substudy within the FOURIER trial, did not show adverse cognitive changes with evolocumab over 19 months median follow-up. Purpose: To investigate the long-term effects of evolocumab on cognitive function. Methods: EBBINGHAUS was a substudy of cognitive function using the Cambridge Neuropsychological Test Automated Battery (CANTAB) within the FOURIER randomized trial of evolocumab vs placebo in patients with established ASCVD. Patients in North America and Europe who completed EBBINGHAUS on study drug were eligible for an open-label extension (OLE) study with evolocumab. The primary endpoint was change in spatial working memory strategy index of executive function score (SWMI) from baseline over time. Secondary endpoints were measures of working memory, episodic memory, and psychomotor speed. A paired t-test was used to compare baseline vs post-baseline scores during OLE. Results: Of 1204 patients from EBBINGHAUS, 306 entered the OLE and were treated with evolocumab for a median of 5.1 years. Median achieved LDL-C was 34 mg/dL (IQR 21-50). No significant change in SWMI occurred during the OLE period overall [mean (±SD) change -0.1±2.7, p=0.73] or when stratified by original randomized allocation ( Figure 1A ). For secondary outcomes, one showed no change during the OLE period, two showed small changes (10-15% of SD), but these were directionally inconsistent (one higher, one lower). In 152 patients originally randomized to evolocumab, there was no significant change in SWMI from randomization through long-term follow-up over a median of 6.7 and a maximum of 7.2 years (mean change 0.1±2.6, p=0.66) ( Figure 1B ). Conclusion: Evolocumab did not lead to any apparent long-term decline in cognitive function through follow-up extending up to 7.2 years.