NEW Warnings Added to Diabetes Drugs

WASHINGTON, April 26 — GlaxoSmithKline and Eli Lilly & Company have added warnings about heart and liver risks to the labels of their diabetes drugs, which are similar to a medication that was withdrawn from the market in 2000 because of links to fatal liver damage. The Food and Drug Administration posted information today about heart and liver risks in Glaxo’s drug, Avandia, and in Actos from Lilly, although warnings were added to the labels earlier.

The F.D.A. posted a summary of risks associated with the medicines on the Medwatch area of its Web site (www.fda.gov) to inform doctors and the public.

Doctors have been watching for signs of liver damage in patients on Avandia and Actos since their introduction in the United States in 1999 because they work the same way as Rezulin, the diabetes medicine that was withdrawn.

GSK’s Response: Millions of diabetics now take the drug Avandia in an effort to lower their blood sugar. It is believed to be far safer than the first drug of its class, Rezulin, which was blamed for nearly 60 deaths due to liver failure before being pulled from the market two years ago.

Now a review conducted by Avandia manufacturer Glaxo SmithKline, offers the best evidence yet that the newer drug does not cause liver problems. Researchers analyzed the results of 22 clinical trials, involving more than 5,000 diabetes patients, and found no evidence of drug-related liver complications. The study was reported in the May issue of the American Diabetes Association publication Diabetes Care.

"Because this study involved such a large number of people, it provides fairly conclusive evidence that [Avandia] is safe to use," says lead author Harold E. Lebovitz, MD, of New York’s SUNY Health Science Center at Brooklyn. Lebovitz is a paid consultant for Glaxo SmithKline.

Avandia and Actos, a similar drug made by Takeda Pharmaceuticals, are two of the most commonly prescribed treatments for type 2 diabetes. Like Rezulin, Avandia and Actos are insulin regulators belonging to a class of drugs known as glitazones. But unlike Rezulin, no deaths or serious liver injury have been reported in users of the two newer drugs.

In this study, liver function measurements were reviewed for just over 5,000 diabetes patients participating in studies of Avandia. The drug was given either alone, or in combination with other insulin-regulating therapies. Lebovitz and colleagues report no evidence of liver toxicity among the patients, and many patients actually had improvement in liver function with treatment.