Public Citizen sued the U.S. Food and Drug Administration (FDA) today for failing to act on its petition to withdraw Darvon, Darvocet and all drugs containing propoxyphene gradually from the market as is now required in the United Kingdom (U.K.).
Public Citizens complaint, filed in the U.S. District Court for the District of Columbia, argues that the FDA is violating the law and putting patients at risk by not acting on Public Citizens Feb. 28, 2006, petition.
Propoxyphene is physically and psychologically addictive, is no more effective than safer alternatives and has been associated with more than 2,000 accidental deaths in America since 1981, Public Citizen told the FDA in its 2006 petition.
Despite the drugs health risks, however, it was one of the 25 most prescribed generic drugs last year, with 22 million prescriptions filled in pharmacies in 2007.
Top FDA drug officials, including Center for Drug Evaluation and Research Director Dr. Janet Woodcock and Dr. Robert Temple, are well aware that this drug has considerable human toxicity, addiction potential and abuse liability, but very limited therapeutic usefulness," said Dr. Sidney Wolfe, director of the Health Research Group at Public Citizen.
"Given this extremely unfavorable ratio of risks to benefits, it is inexcusable that the FDA did not take propoxyphene off the market long ago. It is our hope that this lawsuit will force the agency to finally begin this desperately needed regulatory process.
The U.K. began a phased withdrawal of Darvocet from the British market in 2005, following the recommendation of the U.K. Committee on Safety of Medicines (CSM).
In its report, the CSM stated that it could not identify any patient group in whom the risk-benefit [ratio] may be positive. The withdrawal was completed at the end of 2007.
However, three years after the British government began its action to withdraw the drug, and two years after Public Citizen petitioned for its phasing out, the FDA still has not done anything to protect Americans from propoxyphenes dangerous side effects.
A large proportion of the deaths from propoxyphene occurred because most of the drug is converted into a metabolite that is highly toxic to the heart, lasts longer in the body than the original compound and results in cardiac depression.
Adverse cardiac events associated with propoxyphene include an interruption of heart transmission of electrical impulses, slowed heartbeats and a decreased ability of the heart to contract properly.
Propoxyphene-acetaminophen, or Darvocet, is more dangerous than acetaminophen (the ingredient in Tylenol) alone, yet a study has indicated that Darvocet is no more effective in treating post-operative pain than acetaminophen, Public Citizen said.
Reports on propoxyphene dosage suggest addiction can occur at less than the maximum recommended daily dose and unequivocally confirm addiction at just twice the recommended daily dose.
In addition, propoxyphene has been deemed inappropriate for the elderly because of its adverse effects on the central nervous system - such as sedation and confusion - that have been found to increase the likelihood of falls and fall-related fractures.
Yet studies have shown that propoxyphene use is widespread in emergency rooms, institutionalized populations and retirement communities.
Public Citizen is asking the court to find that the FDAs delay in ruling on the 2006 petition is unlawful and to order the FDA to issue a decision on the petition.
