A Senate report said Saturday that drug maker GlaxoSmithKline knew of possible heart attack risks tied to Avandia, its diabetes medication, years before such evidence became public.
Sen. Max Baucus, chairman of the Senate Finance Committee, and Chuck Grassley, the committee's ranking Republican, released the report, which follows a two-year inquiry, 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.
Based on its knowledge of the heart attack risks, GlaxoSmithKline "had a duty to sufficiently warn patients and the FDA of its concerns in a timely manner," the report said.
Instead, the company tried to downplay findings that the drug could increase cardiovascular risks while also working to downplay findings that a rival medication might reduce such risks, it said.
GlaxoSmithKline said in a statement the drug is safe. It said the committee report took data out of context from analyses of Avandia.
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.
Later that year, the FDA ordered a warning to be included on Avandia's label warning that it might increase the risk of heart attacks. But the label also says data on the risks are inconclusive.
"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," GlaxoSmithKline said.
In a letter to FDA Commissioner Margaret Hamburg that was also released Saturday, the senators said the documents the committee reviewed included an analysis conducted by two safety officials at the agency. The analysis compared Avandia to Pfizer Inc.'s Actos diabetes drug, and found that Avandia has an increased risk of heart attack and heart failure.
The letter also quoted the researchers as saying that said the study itself was dangerous, as it meant patients continued to take the drug.
FDA spokesman George Strait said the FDA is reviewing new data on Avandia and will present those findings to an advisory committee this summer.
"Meanwhile, Commissioner Hamburg is reaching out to ensure that she has a complete understanding and awareness of all of the data and issues concerning this drug," Strait said.