The widely used diabetes drug Avandia should remain on the market because its benefits outweigh the risks, but it should carry a strong warning about an increased risk of heart disease, a federal advisory panel said Monday.
The committee concluded that the evidence suggests an increased heart disease risk is associated with its use, but that the evidence is not sufficiently strong to require the drug's removal from the market.
The Food and Drug Administration generally follows its advisory panel's recommendations, but is not obligated to do so.
The panel said that certain high-risk groups should not take the drug, including people taking nitrates, such as nitroglycerin, to ease pain from angina, and those taking insulin for Type 2 diabetes.
"Physicians will have to think twice before they prescribe the drug for these people," said the panel's chair, Dr. Clifford J. Rosen of the Maine Center for Osteoporosis.
Avandia and another drug in the same family, Actos, already carry a warning against its use by patients with congestive heart failure, and the FDA recently asked both manufacturers to upgrade to a so-called black-box warning, giving it greater prominence.
The panel did not agree on how strong the new warnings should be.
Dr. Robert J. Meyer, director of FDA's Office of Drug Evaluation II, said there was "a fairly unanimous recommendation that came to us," and that the agency would evaluate it carefully in considering labeling changes.
An estimated 21 million Americans have Type 2 diabetes, which most often manifests itself after age 40 and is associated with obesity. About 1 million Type 2 diabetics take Avandia, which had annual sales of $3.4 billion in 2006. However, sales have slumped 20% since May and could further drop when additional warnings are added. The current uproar about Avandia, whose generic name is rosiglitazone, was triggered by a May report in the New England Journal of Medicine linking Avandia to a 43% increase in myocardial ischemia. Ischemia is an inadequate flow of blood to the heart caused by a partial obstruction of an artery and is often a precursor to a heart attack.
Two other analyses, one conducted by the FDA and one by Avandia's manufacturer GlaxoSmithKline, yielded similar results, indicating that the drug increases the risk of myocardial ischemia by 30% to 40%.
