Treatment with a new drug called torcetrapib increased high-density lipoprotein (HDL; "good") cholesterol in individuals with low HDL levels, as well as decreasing the levels of low-density lipoprotein (LDL; "bad") cholesterol. Torcetrapib is a blocker of a cell chemical called cholesterol ester transfer protein (CETP). Individuals who do not have CETP because of a genetic defect have significantly elevated HDL levels. This discovery led to the finding that CETP inhibition may be a novel way of raising HDL, the researchers explained in the New England Journal of Medicine, April 8, 2004.
The investigators treated 19 participants who had low HDL levels with an inactive placebo for 4 weeks. After 4 weeks, the participants were given another 4 weeks of either torcetrapib alone or in combination with the statin atorvastatin. The results showed a 46% HDL increase in the once-daily torcetrapib-only group and a 61% rise in the once-daily torcetrapib/atorvastatin group. The third phase of the study involved 6 participants receiving torcetrapib twice daily for another 4 weeks. In this group, HDL rose 106%, and LDL decreased by 8% to 17%.