WASHINGTON (AP) -- A consumer advocacy group is calling on the Food and Drug Administration to add a boxed warning to the blood thinner Plavix about the risks of major bleeding when used by patients who have received artery-opening stents.
The group Public Citizen says regulators should warn doctors and patients that taking the widely-prescribed drug for more than a year after receiving a drug-coated stent can lead to fatal bleeding.
Plavix, known generically as clopidogrel, is often prescribed to reduce the risk of heart attack in patients who have received a stent to prop open their arteries. But according to clinical trials cited by Public Citizen, the drug offers no protective effect on the heart after one year. Instead, the drug increases the risk of major bleeding, which can sometimes be fatal.
"The research shows that using this drug for more than 12 months puts people at risk of potentially life-threatening bleeding, without any evidence that it's doing any good at that point," said Dr. Sidney Wolfe, of Public Citizen's Health Research Group.
The prescribing label for clopidogrel already mentions that the drug "increases the risk of bleeding." But the warning proposed by Public Citizen would highlight the risk in a black box at the top of the label.
Public Citizen filed its petition with the FDA on Wednesday morning.
In 2012, more than 1 million drug-coated stents were implanted in U.S. patients, according to figures from the group. U.S. pharmacies filled more than 25 million prescriptions for clopidogrel in the last year for which data are available, through June 2013, according to IMS Health.
First marketed by Bristol-Myers Squibb Co. and Sanofi, Plavix was the world's second-bestselling drug until it lost patent protection last year. The drug is now marketed in generic versions by more than a half-dozen companies.