Triglyceride Levels, Alirocumab Treatment, and Cardiovascular Outcomes After an Acute Coronary Syndrome

Abstract

Background: It is unknown whether clinical benefit of proprotein convertase subtilisin/kexin type 9 inhibitors is associated with baseline or on-treatment triglyceride concentrations.

Objectives: This study sought to examine relations between triglyceride levels and the effect of alirocumab vs placebo on cardiovascular outcomes using prespecified and post hoc analyses of the ODYSSEY OUTCOMES (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) trial.

Methods: Patients with recent acute coronary syndrome (ACS) (n = 18,924) and elevated atherogenic lipoproteins despite optimized statin therapy were randomized to alirocumab 75 to 150 mg or matching placebo every 2 weeks subcutaneously. Major adverse cardiovascular events (MACE) were examined in relation to continuous or dichotomous triglyceride concentrations.

Results: Median baseline triglyceride concentration was 129 mg/dL. In both treatment groups, a 10-mg/dL higher baseline concentration was associated with an adjusted MACE HR of 1.008 (95% CI: 1.003-1.013; P < 0.005). Baseline triglycerides ≥150 vs <150 mg/dL were associated with a HR of 1.184 (95% CI: 1.080-1.297; P < 0.005). Versus placebo, alirocumab reduced low-density lipoprotein cholesterol from baseline (average, 54.7%) and reduced MACE (HR: 0.85; 95% CI: 0.78-0.93). At month 4, triglyceride levels were reduced from baseline by median 17.7 mg/dL (P < 0.001) and 0.9 mg/dL (P = NS) with alirocumab and placebo, respectively. A 10-mg/dL decline from baseline in triglycerides was associated with lower subsequent risk of MACE with placebo (HR: 0.988; 95% CI: 0.982-0.995; P < 0.005) but not with alirocumab (HR: 0.999; 95% CI: 0.987-1.010; P = 0.82).

Conclusions: Among patients with recent ACS on optimized statin therapy, baseline triglycerides was associated with cardiovascular risk. However, the reduction in triglycerides with alirocumab did not contribute to its clinical benefit. (ODYSSEY Outcomes: Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab; NCT01663402).

Keywords: cardiovascular risk; clinical trial; lipids; proprotein convertase subtilisin/kexin type 9 inhibitor.