FDA panel says diabetes drug should stay on market
By Lisa Richwine
BETHESDA, Md., March 26 (Reuters) - The controversial diabetes drug Rezulin should stay on the market, even though 28 people have died from liver failure after taking it, experts told the U.S. Food and Drug Administration (FDA) on Friday.
The drug, made by Warner-Lambert's <WLA.N> Parke-Davis division, has caused at least 40 cases of severe liver disease -- some so bad the patients had to have liver transplants.
But a panel of doctors who advise the FDA said the drug should still be approved for use with the older diabetes drugs insulin and the sulfonylurea drugs.
However, they said the drug might be too risky to make it worth taking by itself.
Parke-Davis says, and the FDA has so far agreed, that the drug's benefits outweigh any risks. Diabetes is the seventh leading cause of death in the United States.
Rezulin, known generically as troglitazone, is the first of a new class of drugs that help the body respond better to insulin. It is used to treat type-II or adult onset diabetes, which affects 15 million Americans and which can lead to blindness or limb loss.
The advisory panel spent Friday hearing evidence about the drug, which has been taken by more than 1.4 million people since it hit the market two years ago. The FDA usually follows the advice of its expert committees, but one consumer group has been calling for the drug to be taken off the market.
David Graham of the FDA's office of post-marketing drug risk assessment said at least 40 cases of acute liver failure had been caused by Rezulin. Of these, 28 people died.
But he said doctors do not report all cases of drug reactions. He estimated the risk of liver injury for a patient taking Rezulin for six months was about one in 1,800. "The longer you stay on Rezulin, the higher the risk you accumulate," he told the panel.
Parke-Davis estimates the risk is closer to 1 in 45,000 patients.
It said the number of liver-related deaths had decreased since last year, when the company warned doctors and other health care workers that the drug could damage the liver. Patients must now take regular liver enzyme tests.
About 15 percent of patients taking Rezulin now use it alone. But the committee recommended withdrawing that approval.
Some members said perhaps Rezulin could be used alone if the labeling on the drug were changed to recommend more frequent monitoring, but they were not convinced it was helpful enough when used alone to make it worth the risk.
"The data makes it very difficult to get our hands on this risk and I think this has troubled everyone," Dr. Henry Bone, director of the Michigan Bone and Mineral Clinic in Detroit, who chairs the panel, said.
The company said it would continue working with the FDA to persuade the agency not to restrict Rezulin's approval.
"Clearly this reaffirms that the benefits outweigh the risks. I think they (doctors) should have renewed confidence when they prescribe it," Dr. Robert Zerbe of Parke-Davis said.
Rezulin faces some stiff competition, even if the FDA does not further restrict its use.
Two new drugs in the same class as Rezulin are expected to hit the market in the next year -- SmithKline Beecham Plc's <SB.L> Avandia, known generically as rosiglitazone, and Eli Lilly & Co.'s <LLY.N> Actos, known as pioglitazone. |
