Trials and Tribulations of CETP Inhibitors

Abstract

The development of CETP (cholesteryl ester transfer protein) inhibitors has had a long and difficult course with 3 compounds failing in phase III clinical trials. Finally, the REVEAL (Randomized Evaluation of the Effects of Anacetrapib through Lipid modification) trial has shown that the CETP inhibitor anacetrapib decreased coronary heart disease when added to statin therapy. Although the result is different to earlier studies, this is likely related to the size and duration of the trial. The benefit of anacetrapib seems to be largely explained by lowering of non-HDL-C (high-density lipoprotein cholesterol), rather than increases in HDL-C. Although the magnitude of benefit for coronary heart disease appeared to be moderate, in part this may have reflected aspects of the trial design. Anacetrapib treatment was associated with a small increase in blood pressure, but was devoid of major side effects and was also associated with a small reduction in diabetes mellitus. Treatment with CETP inhibitors, either alone or in combination with statins, could provide another option for patients with coronary disease who require further reduction in LDL (low-density lipoprotein) and non-HDL-C.

Keywords: anacetrapib; coronary disease; dalcetrapib; evacetrapib; torcetrapib.

Figure 1

CETP inhibition reduces LDL-C levels by three mechanisms, 1) decreased transfer of HDL CE into triglyceride-rich lipoproteins which are converted into LDL; 2) decreased transfer of HDL CE into LDL; and 3) increased uptake of LDL particles by the hepatic LDL receptor.