The U.S. Food and Drug Administration has said that starting on November 18, 2011, it will restrict retail pharmacy sales of three diabetes drugs manufactured by GlaxoSmithKline: the stand-alone Avandia (rosiglitazone) and the combination drugs Avandamet (rosiglitazone and metformin) and Avandaryl (rosiglitazone and glimepiride).
The market restrictions are motivated by the agency’s concerns that the drugs increase the risk of heart attacks. To continue taking the drugs, diabetes patients and their prescribers must be enrolled in the Avandia-rosiglitazone Medicines Access Program, a mail-order program run by FDA-certified pharmacies. To enroll, patients will have to show that they cannot successfully control their blood sugar levels with other drugs.
The FDA restriction is the latest in a series of setbacks for what was once the world’s best-selling diabetes drug, peaking at $3.2 billion in worldwide sales in 2006. But concerns about subsequent studies, which raised questions about Avandia’s effects on bone density and an increased risk of heart attacks, cut deeply into sales. In 2010, sales were $680 million-down almost 80 percent in four years from their high.
The current number of U.S. Avandia users is hard to determine. The FDA’s latest figures, from October 2010, showed 119,000 patients filling prescriptions for it, down substantially from 235,500 patients in January 2010.
Glaxo, which is informing U.S. pharmacies now about the November deadline, has advised pharmacists and healthcare providers to caution patients currently taking Avandia not to stop taking it without consulting a medical professional.