Future Cloudy for GSK’s Avandia
A panel of FDA advisors decided yesterday that GlaxoSmithKline’s diabetes drug Avandia should either be withdrawn from the market or its use seriously restricted. The panel had been assembled after several years of ongoing questions over the safety of the drug, which has been linked to an increased risk of cardiovascular events.
The final vote came down to this: 12 panel members said the drug should be removed from the market, while 10 said it could stay on the market, but with strong restrictions on who could both prescribe and take the drug. The remaining members voted to either keep the label the same or revise it somehow to better reflect the safety concerns.
With that mixed bag in hand, its up to FDA to decide what to do.
For those of you having trouble keeping track of the ins an outs of the Avandia story, here’s a little primer. GlaxoSmithKline’s Avandia problems—the public ones, at least—began in May 2007, when the safety of the drug was questioned by Cleveland Clinic cardiologist Steve Nissen, previously known for blowing the lid off the cardiovascular issues associated with Merck’s arthritis drug Vioxx. In an article in The New England Journal of Medicine, Nissen said an analysis of the combined data from 42 previous clinical trials of Avandia showed that patients taking the drug were 43% more likely to have a heart attack than those who weren’t. FDA issued a safety alert about the drug, which brought in $3 billion for GSK in 2006.
In August 2007, an FDA advisory panel voted 22-1 to keep Avandia on the market. Still, Avandia franchise sales fell 22% to $2.4 billion in 2007.
But GSK’s troubles with Avandia go beyond the financial pain of lost sales. As you might expect, the company is at the receiving end of a flood of lawsuits related to the drug. It could get worse. This week, the NY Times said it had reviewed internal documents suggesting GSK knew as early as 1999 that the drug posed a safety risk, but actively worked to conceal those findings from FDA. Yesterday, GSK said it would take a charge of $2.36 billion in the second quarter, in part to help pay to settle lawsuits related to Avandia and its antidepressant Paxil.
Avandia works by lowering blood glucose levels by increasing cells’ responsiveness to insulin. This isn’t the first time drugs acting on Avandia’s target, the peroxisome proliferator-activated receptor (PPAR), have run into safety trouble. In 2005, Merck and Bristol-Myers Squibb withdrew a New Drug Application for their PPAR agonist Pargluva after FDA asked for a five-year cardiovascular safety study. And Warner-Lambert pulled the drug Rezulin from the market in 2000 after it was shown to cause liver toxicity.