New Merck Drug Anacetrapib Improves Cholesterol Profile in Clinical Trial
Although total cholesterol is an important number to keep within normal limits, also important is the levels of “good” and “bad” cholesterol. An experimental drug by Merck and Co called anacetrapib being tested in a Phase III clinical trial appears to safely help raise the good kind while slashing the bad.
Anacetrapib Boosted HDL Cholesterol by 138% in Clinical Trial
Anacetrapib belongs to a class of medications called CETP inhibitors which work by inhibiting a compound called cholesteryl ester transfer protein which mediates the transfer of cholesterol and triglycerides between lipoprotein particles. Inhibiting this protein boosts HDL “good” cholesterol levels.
A similar drug called torcetrapib was previously introduced by Pfizer Inc, however in addition to affecting cholesterol levels, that drug unintentionally increased blood pressure, electrolytes, and the hormone aldosterone which affects kidney function, increasing the risk of death.
Another CETP inhibitor, dalcetrapib, is also in phase III testing in clinical trials but with a milder lipid effect on the order of about 40% increase in HDL and a 15% drop in LDL, noted study discussant Thomas F. Lüscher, MD, of the University Hospital in Zurich, Switzerland.
“This class, if it works, could be as big as the statins,” said Steven Nissen, head of cardiology at the Cleveland Clinic in Ohio, who led one of the Pfizer trials. “If we can reduce event rates another 25 percent above what statins do, that will save a lot of lives.”
In data published in the New England Journal of Medicine and reported at the American Heart Association’s 2010 Scientific Sessions in Chicago this week, a clinical trial of 1,623 patients called DEFINE (Determining the Efficacy and Tolerability of CEPT Inhibition with Anacetrapib) showed that those taking anacetrapib had an average 40% drop in LDL cholesterol and a 138% rise in HDL cholesterol. The patients were all at high risk for coronary heart disease and were also simultaneously taking a statin drug.
There were no signs of increased blood pressure or levels of aldosterone with anacetrapib. Also, fewer patients in the Merck trial needed procedures to clear clogged heart arteries.
A final clinical trial on anacetrapib entitled REVEAL will begin next year and include 30,000 high-risk patients. That trial will be powered to detect an effect on major atherosclerotic events such as MI. Merck anticipates that if the trial goes well, it would file for regulatory approval in 2015.
Cannon CP, et al "Safety of anacetrapib in patients with or at high risk for coronary heart disease" N Engl J Med 2010; DOI: 10.1056/NEJMoa1009744.