Diabetes drug Avandia faces a moment of truth Wednesday, when a committee will decide whether to recommend pulling it from the market because it has been associated with increased heart problems.
The committee, convened at the request of the Food and Drug Administration, began its work on Tuesday as two US senators said Avandia manufacturer GlaxoSmithKline (GSK) hid studies showing the drug raised the risk of heart attacks and strokes.
The studies reportedly linked Avandia to deadly cardiovascular side effects soon after it hit the market in 1999.
The drug has come with a warning about potentially serious side effects since 2007, after the FDA conducted a comparative study that showed it increased the risk of heart attack and stroke.
Numerous recent meta-analyses of clinical research and epidemiological studies have also found Avandia poses more risk to patients' heart health than a similar drug, Actos, made by Japanese firm Taketa.
Both drugs help patients with Type 2 diabetes to keep their blood sugar under control.
Among the damning information released by Senators Charles Grassley and Max Baucus Tuesday was testimony from a former FDA official who confirmed Glaxo had declined to make public studies that linked Avandia to serious side-effects.
"The documents we uncovered in our investigation will help arm the FDA with the best information possible as it evaluates Avandia's safety," Baucus said.
Glaxo spokeswoman Mary Anne Rhyne said the official's allegations and the material released by Baucus and Grassley had been "intentionally taken out of context."
The documents "are a small subset of the 14 million pages of documents that have been provided" by GSK in the course of litigation over Avandia.
The official's testimony and Glaxo's 2001 study of Avandia are part of thousands of pages of documents under seal at a Philadelphia where some 8,000 lawsuits are still pending against the British pharmaceutical firm.
Glaxo has sought to defend Avandia, including with a clinical study carried out in Europe entitled "Record," which found the drug carried no increased cardiovascular risks.
But the result of that study have been challenged by FDA expert Thomas Marciniak, and Glaxo looks at serious risk of seeing its one-time blockbuster drug pulled from the market.
The committee of experts has the power to issue an advisory ruling only, but the FDA usually follows its recommendations.
A ruling in favor of pulling Avandia, which generated some 1.2 billion dollars in 2009, would be a serious blow to Glaxo, Britain's biggest pharmaceutical firm.
There are close to 300 million diabetics worldwide, including some 23 million in the United States, and cardiovascular problems remain a leading cause of death among sufferers of the disease.
Europe's medical regulatory body will begin evaluations of Avandia on July 19.
Copyright 2010 AFP Global Edition
