The Food and Drug Administration said Friday that Xanodyne Pharmaceuticals has agreed to halt marketing of Darvon and the related brand Darvocet, which have been subject to safety concerns for decades.
The FDA has also called on generic drugmakers to stop marketing low-cost drugs containing the active ingredient in Darvon, called propoxyphene.
About 10 million people in the U.S. received prescriptions for Darvon and related drugs in 2009, according to the FDA.
Friday's action puts the U.S. in line with Britain and the European Union, which previously decided to ban Darvon due to suicides and accidental overdoses.
FDA officials said they decided to take action based on a recent study showing Darvon interferes with the electrical activity of the heart, causing irregular heart rhythms that can be fatal.
"With the new study results, for the first time we now have data showing that the standard therapeutic dose of propoxyphene can be harmful to the heart," Dr. Gerald Dal Pan, director of FDA's office of surveillance and epidemiology said in a statement.
Dal Pan said patients taking Darvon should continue taking the medication until their doctor prescribes a replacement therapy. Other commonly-prescribed opioid drugs for pain include oxycodone and morphine.
Darvon, which was first approved in the 1950s, is an opioid narcotic used to treat mild to moderate pain. The consumer watchdog group Public Citizen had petitioned the FDA to ban the drug, saying its benefits didn't justify a risk that added up to several hundred deaths a year.
And at a public FDA meeting held in January 2009, a panel of outside experts voted 14-12 that the drug should be pulled from the market.
But the FDA disagreed, and later that year agency officials said they would keep the drug on the market with a bolder warning label about the risk of overdoses.
Based in Newport, Ky., Xenodyne Pharmaceuticals is a privately-held company focused on pain-relieving drugs.
Darvocet, which combines propoxyphene with the more common painkiller acetaminophen, is more popular than Darvon. At FDA's 2009 meeting on the drug, officials cited studies showing most of the pain relief from Darvocet came from the acetaminophen component.
In the last two years the FDA has begun prodding drugmakers to develop more sophisticated pain relievers that are harder to abuse or misuse. Recently-developed products include pills that are formulated to lose their potency if they are crushed or dissolved.
