Why did it take so long to ban Darvon, Darvocet?

In a study on dogs conducted by researchers at Lilly, the company that discovered the now-banned prescription painkiller propoxyphene, researchers determined that “cardiac conduction depression may be a factor in some of the (human) cardiac toxicities associated with propoxyphene overdose.” That study was held more than 30 ago. In 2009, researchers used the same kind of function measure for the human study that led to the banning last month of propoxyphene, known by the brand names Darvon and Darvocet.

Why would the FDA take so long to pull propoxyphene-containing products from the market if data from three decades ago proved the drug was dangerous? The watchdog group Public Citizen asks the same question in a recent press release.

Public Citizen first petitioned the FDA to pull the drug in 1978 because of concerns that the drug was dangerous, but the FDA refused to hear the matter, citing insufficient data. After the UK voted to ban the drug in 2006, the group petitioned the FDA again. The petition was heard by an expert panel, which in 2009 voted to remove the drug from the U.S. market. But the FDA overruled that decision, opting instead to conduct studies on how the drug affects the heart. This decision was made despite the banning of propoxyphene just weeks earlier by the European Medicines Agency.

Public Citizen says this negligence has put millions Americans at risk and has lead to at least 2,000 deaths that otherwise could have been prevented. “We will ask for and support a congressional investigation into whom at the FDA, specifically in the Center for Drug Evaluation and Research, was responsible for the loss of so many lives in this country,” the release states. “It is clear that long before today, many drug safety experts in the Office of Surveillance and Epidemiology had decided the drug should be removed from the market.”