Observational epidemiologic studies have reported that low plasma concentrations of high-density lipoprotein (HDL) cholesterol are an independent risk factor for occlusive cardiovascular disease (CVD), including coronary heart disease (CHD) and ischemic stroke.
1,2 Given these associations, therapeutic strategies to reduce CVD risk by increasing HDL cholesterol concentrations have attracted considerable interest. One such approach is through pharmacologic inhibition of cholesterol ester transfer protein (CETP), which transfers esterified cholesterol from HDL to apolipoprotein B–containing lipoproteins, including very low-density lipoprotein (VLDL), in exchange for triglycerides.
3 The first CETP inhibitor assessed in phase 3 trials, torcetrapib, was associated with increased CVD risk, probably owing to off-target effects.
4,5 Subsequent trials of dalcetrapib (which had only modest effects on HDL cholesterol) or evacetrapib (which increased HDL cholesterol levels substantially and lowered LDL cholesterol levels) were stopped early for futility after 2 to 3 years of treatment in high-risk individuals.
6,7 A trial of the potent CETP inhibitor anacetrapib (which doubled HDL cholesterol levels and lowered non-HDL cholesterol levels by about one-fifth) that involved approximately 30 000 high-risk individuals treated for 4 years recently reported a benefit for risk of major coronary events consistent with the effects of lowering non-HDL cholesterol levels.
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