Diabetes Drug Fails to Slow Artery Plaque Build-Up

The controversial diabetes pill Avandia failed to significantly slow plaque buildup in heart arteries compared with an older drug, though there were some hopeful signs in a new study reported Wednesday.

Avandia, once a blockbuster drug made by British-based GlaxoSmithKline PLC, has been under a cloud since May 2007, when a medical journal report suggested it may raise the risk of heart attacks and heart-related deaths. The American Diabetes Association recently said patients should avoid using it until safety questions are resolved.

The new study tested Avandia against glipizide, sold as Glucotrol by Pfizer Inc. and in generic form, in 672 people in 19 countries. All had Type 2 diabetes, the most common form of the disease and the one linked to obesity. All were at high risk for heart problems and many were very overweight.

Doctors measured the thickness of plaque starting to form in a heart artery of each participant at the start of the study and 18 months later. Those on Avandia had a slight reduction in buildup versus a little increase in those on glipizide, but the difference was so small that the results were a statistical draw.

Avandia did show a significant advantage in a second measure of artery plaque, but this was not the main result being tested.

Dr. Richard Nesto of Lahey Clinic in Burlington, Mass., and Brigham and Women's Hospital in Boston led the study and reported results Wednesday at an American Heart Association conference.

"This is now the second study that was unable to show a beneficial effect," said Dr. James Stein, director of preventive cardiology at the University of Wisconsin-Madison, who had no role in the research.

"People really shouldn't be using this to treat diabetes" because safer and more effective medicines are available, Stein said.

The results give "one more reason" to use Avandia with caution, said Dr. Steven Nissen, the Cleveland Clinic cardiologist who did the 2007 analysis that suggested heart risks from the drug. He also led a similar study of Avandia's chief competitor — Actos, by Japan-based Takeda Pharmaceuticals — which did show reduction in artery plaque.

Studies so far have been too small to confirm or rule out safety issues with Avandia. A large study aimed at doing that is not expected to finish for two years.