ATLANTA, March 13 (Reuters) — A statin drug has been shown for the first time to reverse the buildup of plaque in coronary arteries, researchers said on Monday.
But the study did not address whether that made a difference in risk of a heart attack or stroke. Other researchers said it remained to be seen whether the results represented a clear advance in treatment.
The study, which began with more than 500 patients, provided each with a high dose of Crestor, a drug made by AstraZeneca. In the 349 patients whose plaque volume could be evaluated, that volume was reduced by 7 percent to 9 percent. The drug also lowered levels of LDL, or bad cholesterol, by more than 53 percent and it raised levels of HDL, or good cholesterol, by nearly 15 percent.
Crestor is considered to be one of the most powerful statins, or cholesterol-lowering drugs, but there has been concern about side effects, including potential muscle damage.
The changes in cholesterol levels seen in the latest study were the largest ever seen in a major trial of statin drugs, said researchers, who presented the results at a meeting of the American College of Cardiology in Atlanta.
"The results were shockingly positive," said Dr. Steven E. Nissen, interim director of the department of cardiovascular medicine at the Cleveland Clinic and the study's lead author.
Dr. Nissen said the trial did not answer the question of whether less plaque means fewer heart attacks and strokes. Atherosclerosis, or blockage in arteries, results when a buildup of cholesterol, inflammatory cells and fibrous tissue called plaques form in an artery wall. If these plaques rupture, they can block blood flow to critical organs, such as the heart or brain, and can lead to heart attack or stroke.
But it is not clear whether reducing the volume of plaque will protect patients. Heart researchers say statins are thought to exert their powerful effects in reducing heart attack risks by making plaque more stable, not necessarily shrinking its size.
Other statin drugs, a class that includes Lipitor by Pfizer, Zocor from Merck and Vytorin, which is sold by Merck and the Schering-Plough Corporation, may lead to similar plaque regression, Dr. Nissen said.
He said he doubted plaque could be reduced by much more than the levels seen in the Crestor trial, which used the highest approved dose for the drug. Dr. Roger S. Blumenthal, an associate professor at the Johns Hopkins University, said the findings were intriguing, but that more study was needed.
AstraZeneca shares rose 2.3 percent, closing up $1.16 at $50.96 a share yesterday on the New York Stock Exchange. Crestor, a critical growth area for the company, was initially estimated by industry analysts to have potential sales of $3 billion to $4 billion a year. But sales, which totaled $1.27 billion last year, have not taken off as fast as hoped, and the drug has failed to win a significant share from Lipitor, a $12 billion blockbuster, after controversy over Crestor's safety.
The Food and Drug Administration last year threw out a petition by consumer group Public Citizen to have Crestor banned. Dr. Nissen said he did not see any unusual safety issues in his study, although he acknowledged the study might not have been long enough to catch some problems.