FDA panel rejects expanded label for aspirin: some support for nonfatal MI indication.(Clinical Rounds)

GAITHERSBURG, MD. -- A federal advisory panel voted against expanding aspirin's indications to include primary prevention of myocardial infarction.

In an 11-3 vote, the Food and Drug Administration's Cardiovascular and Renal Drugs Advisory Committee recommended against adding to aspirin's label a statement that the drug can help prevent both fatal and nonfatal MIs. Aspirin currently is indicated for secondary prevention of MI.

During the panel's meeting last month, 6 of the 14 members agreed that the data did support a recommendation that aspirin be approved for primary prevention of nonfatal MIs, but some panelists said that this had been shown only in men.

The meeting was held in response to a citizen's petition fried with the FDA in February by Bayer Healthcare. The petition requested that the labeling for aspirin be expanded to include a recommendation for the use of aspirin, at dosages of 75-325 mg/day, for the primary prevention of MI in patients at moderate risk (those with at least a 10% risk of coronary heart disease over 10 years in whom the benefits outweigh the risks of aspirin).

The FDA has considered this indication before, and held advisory panel meetings on the topic in 1989 and in 1997, but the primary prevention indication was not recommended.

Since 1998, however, three new studies have been published: the Thrombosis Prevention Trial, the only study that enrolled a moderate-risk population; the Hypertension Optimal Treatment study; and the Primary Prevention Project. And in 2002, the American Heart Association and the U.S. preventive Services Task Force adopted clinical guidelines recommending primary prevention with aspirin for patients at moderate to high risk of coronary heart disease.

At the meeting, Bayer presented data from five primary prevention studies to support the claim. The findings on more than 55,000 patients "provide clinically meaningful data for efficacy and safety" in the moderate-risk population, said Dr. Thomas Pearson, the Albert D. Kaiser professor and chair of community and preventive medicine at the University of Rochester (N.Y.). Two of the trials were stopped early because of evidence that aspirin was effective, he said, noting that four of the studies yielded consistent findings.