Evacetrapib missed its primary MACE endpoint compared with placebo among patients with high-risk vascular disease, including those who were homozygous (AA) for polymorphism rs1967309 of the ADCY gene, in a large nested case-control analysis of the ACCELERATE trial.
The results contradict those for another cholesteryl ester transfer protein (CETP) inhibitor – dalcetrapib – which has shown significant cardiovascular benefits only among AA patients.
“Although directionally similar to the dalcetrapib analysis, there was no significant interaction between genotype and cardiovascular outcome with evacetrapib,” Steven E. Nissen, MD, and his associates wrote simultaneously in JAMA Cardiology and reported at the annual meeting of the American College of Cardiology.
Four CETP inhibitors have reached full-scale development: evacetrapib, dalcetrapib, torcetrapib, and anacetrapib. They all markedly increase circulating HDL, and all except dalcetrapib cut circulating LDL. But those benefits largely haven’t extended to the key endpoint, major adverse cardiovascular events (MACE). In large trials, torcetrapib increased MACE, anacetrapib reduced MACE by such a small amount that its maker did not file for FDA approval, and evacetrapib and dalcetrapib had no effect on MACE.
But there was a caveat for dalcetrapib. In a post-hoc analysis of its placebo-controlled trial, the CETP inhibitor reduced MACE by 39% among AA individuals and increased MACE by 27% among GG individuals, those homozygous negative for the SNP rs1967309.
These findings could make sense because ADCY gene variants have been linked to carotid intimal medial thickness, high-sensitivity C-reactive protein, and cholesterol efflux capacity, wrote Dr. Nissen of the department of cardiovascular medicine, Cleveland Clinic, Cleveland, Ohio (JAMA Cardiol. 2018 Mar 11. doi: 10.1001/jamacardio.2018.0569).
To explore whether ADCY genotypep also affects evacetrapib response, he and his associates compared 1,427 cases with MACE with 1,532 matched controls from the international, randomized, double-blind ACCELERATE (Assessment of Clinical Effects of Cholesteryl Ester Transfer Protein Inhibition with Evacetrapib in Patients at a High Risk for Vascular Outcomes) trial (NCT01687998). Participants had cerebrovascular atherosclerotic disease, peripheral arterial disease, coronary artery disease with diabetes, or recent acute coronary syndrome. They received oral evacetrapib (130 mg) or placebo, and the primary endpoint was a composite of cardiovascular death, myocardial infarction, stroke, coronary revascularization, or hospitalization for unstable angina.
Evacetrapib missed this primary endpoint in all genetic subgroups. Odds ratios for evacetrapib compared with placebo were 0.88 (95% confidence interval, 0.69 to 1.12) among AA patients, 1.04 (95% CI, 0.90 to 1.21) among heterozygous (AG) patients, and 1.18 (95% CI, 0.98 to 1.41) among GG patients. A test for interaction also was insignificant (P = .17). A test for trend nearly reached significance (P = .06), but weakened when the investigators controlled for cardiovascular risk factors or looked only at hard cardiovascular outcomes, they said.
Thus, the relationship between evacetrapib response and AA genotype “was far less in magnitude than observed in the pharmacogenetic study with dalcetrapib,” they wrote. Dalcetrapib is a weaker CETP inhibitor than evacetrapib, the study populations weren’t identical, and the trials used different statistical methods, all of which could explain the discrepant findings, they added. “The completion of the dalcetrapib pharmacogenetics outcome trial should clarify whether this is a false signal or a paradigm-shifting discovery.”
Eli Lilly provided funding, helped design and conduct the study, and helped write the manuscript. Dr. Nissen reported receiving grants and nonfinancial support from Eli Lilly while conducting the study. Several coinvestigators also disclosed ties to Eli Lilly and six reported being employees of the company.
Source: JAMA Cardiol. doi:10.1001/jamacardio.2018.0569.