The diabetes drug Avandia, once the world's top-selling diabetes medication, took two more hits Monday with one new study linking it to an increased risk of heart attacks and a separate study linking it to an increased risk of heart failure and stroke. The research comes only weeks before an upcoming federal hearing to reconsider its fate.
The drug, also known by its generic name rosiglitazone, was approved in 1999 to help people with Type 2 diabetes control their blood sugar. At the time, it was considered a safer alternative than existing diabetes drugs. Soon after approval, the drug was linked to an increased risk of heart failure and bone fractures; worries about the drug's safety increased in 2007 when a meta-analysis pooling of previous studies concluded that the drug increased the risk of heart attack.
One of the studies released Monday, a larger analysis, found Avandia raised the risk of heart attacks by 28 percent to 39 percent compared with other diabetes medications. The study was published online in the Archives of Internal Medicine.
The other study, an observational study of Medicare recipients published online in the Journal of the American Medical Association, found Avandia increased the risk of stroke by 27 percent, heart failure by 25 percent and death from any cause by 13 percent compared with another diabetes drug, Actos.
"We have two studies done by independent groups, published in very responsible journals using different approaches coming to the same conclusion," said Dr. Steven E. Nissen, chairman of the department of cardiovascular medicine at the Cleveland Clinic Foundation and the lead author of the Archives study and the 2007 analysis. "It's everything we know about this drug during its very sad and unfortunate history."
Both studies are scheduled for print publication in July. They were released early in advance of a Food and Drug Administration hearing on July 13 and 14 that will consider whether Avandia should remain on the market.
The drug's manufacturer, GlaxoSmithKline, defended Avandia on Monday, saying that the studies stand in contrast to a randomized clinical trial of 4,447 patients conducted by Glaxo. That study found rates of hospitalization and deaths from cardiovascular events were similar among Avandia patients and those taking other diabetes medications, such as metformin and surfonylurea.