About 40,000 Australians taking the diabetes drug Avandia have been told to urgently consult with the doctor about whether they should continue receiving the drugs.
The action was announced Wednesday by GlaxoSmithKline, the maker of Avandia, after they were ordered to issue new safety warnings in Australia for patients with certain medical conditions, such as mild forms of heart failure and unstable angina.
The Therapeutic Goods Administration (TGA), which is the Australian equivalent of the FDA in the United States, recently ordered changes to the guidelines for use of Avandia due to health concerns about heart side effects associated with the drug.
Avandia, which is known generically as rosiglitazone, is used to treat Type 2 diabetes by controlling blood sugar levels. It was a top selling drug, with annual sales of over $3 billion worldwide, until a study published in the New England Journal of Medicine in May 2007 indicated that users face a 43% increase in the risk of heart attacks and a 64% increase in the risk of cardiovascular death.
The new Australian guidelines indicate that Avandia should not be prescribed to patients who are on insulin or to patients with a history of cardiac problems. In addition, new patients should not be started on triple therapy, which is a course of three drugs: sulfonylurea, metformin and Avandia. The guidelines also apply to Avandamet, which is another drug that contains Avandia.
In November 2007, the FDA added a black box warning to the drug in the United States about Avandia side effects which could increase the risk of a heart attacks and congestive heart failure. Although many experts called for an Avandia recall in the U.S. due to the safety concerns, the FDA has allowed the diabetes drug to remain on the market with the strongest warnings possible, pending further studies.