This is the finding of a two year, 334 page study by the Senate Finance Committee.
Sen. Max Baucus, chairman of the Senate Finance Committee, and Chuck Grassley, the committee's ranking Republican, released the report on Saturday. They are also asking the U.S. Food and Drug Administration why it allowed a clinical trial of Avandia to continue even after the agency estimated that the drug caused 83,000 heart attacks between 1999 and 2007.
And senators accuse drug maker GlaxoSmithKline, or GSK, of ignoring these potentially deadly side effects for years.
In a statement released Saturday, the Committee said, "The totality of evidence suggests that GSK was aware of the possible cardiac risks associated with Avandia years before such evidence became public. Based on this knowledge, GSK had a duty to sufficiently warn patients and the FDA of its concerns in a timely manner."
GSK is defending its product saying, "Contrary to the assertions in the report, and consistent with the FDA-approved labeling, the scientific evidence simply does not establish that Avandia increases cardiovascular ischemic risk or causes myocardial ischemic events."
Glaxo Smith Kline says it's open to scientific debate.
In May 2007, the New England Journal of Medicine published an analysis of dozens of studies on nearly 28,000 people who had taken Avandia. The journal said there was a 43 percent higher risk of heart attack for those taking Avandia compared to people taking other diabetes drugs or no diabetes medication. The findings raised concerns because two-thirds of the people with Type 2 diabetes, the most common form, die of heart problems.
Avandia was Glaxo's third best-selling drug in 2006 with revenue of $2.2 billion. But the safety concerns disclosed the following year slashed revenue to $1.2 billion by the end of 2008.
Avandia is intended to control blood sugar by increasing the body's sensitivity to insulin, a protein critical to digesting sugars.
Insulin-regulating treatments have long been presumed to lessen the heart risks already associated with diabetes, which is linked to obesity.
On the Net:
Finance Committee letter and report:
Food and Drug Administration: www.fda.gov