The trial, led by the University of Oxford and funded by Merck, did not find a significant difference in the risk of ischemic stroke.
The researchers noted that anacetrapib raised blood levels of good cholesterol by a mean of 43 mg per deciliter compared to the placebo. The drug also lowered levels of non-HDL cholesterol by 17 mg per deciliter -- a level associated with a 10 percent reduction in the risk of coronary death or heart attack.
"This result reduces the likelihood that other actions of anacetrapib played a major role in modifying the risk of coronary events," researchers concluded.
Martin Landray from Oxford, one of the principal investigators, added: "The large increase in HDL cholesterol levels produced by anacetrapib did not appear to have much impact on risk."
Merck said safety data was generally consistent with earlier trials - anacetrapib patients had slightly higher blood pressure levels than the placebo group - but an analysis showed that the experimental drug accumulates in adipose tissue.
It found that the amount of anacetrapib in fat tissue fell only a small amount a year after treatment ended. Although animal studies have not indicated harm from this, Merck plans a two-year follow up of patients to study long term effects.
This article was provided by Reuters.