Two U.S. Food and Drug Administration advisory panels will hold a joint meeting on July 30th to discuss whether the diabetes drug Avandia (rosiglitazone)raises the risk of heart attacks to the point that sales should be restricted or barred.

The FDA's Endocrinologic and Metabolic Drugs advisory committee and the Drug Safety and Risk Management advisory panel will discuss cardiovascular risks associated Avandia's class of drugs, thiazolidinediones.

Safety questions about Avandia burst into the headlines in May when Cleveland Clinic cardiologist Dr. Steven Nissen published an analysis of 42 relatively short-term studies showing Avandia increased the risk of heart attacks by 43 percent.

The FDA's outside expert advisors will be asked if Avandia does raise "cardiac ischemic risk" based on clinical studies to be presented at the meeting and whether "there is evidence that this risk is greater than other available therapies" for type 2 diabetes.

Avandia and Actos, a similar drug, have long been shown to increase the risk of heart failure, but the July 30th meeting will focus on the risk of heart attacks rather than the risk of heart-failure. Actos has not been linked to the same heart-attack risk as Avandia.

The advisory panels will be asked to vote whether Avandia should be limited to certain patients, or if a "black box" warning should be added.

GlaxoSmithKline has strongly defended the safety record of Avandia and two other combination drugs sold under the brand names Avandamet and Avandaryl that include the same active ingredient.