In a November 16 safety announcement, the Food and Drug Administration (FDA) said it is evaluating preliminary data from a clinical trial showing an increased overall risk of death for patients treated for 30 months with dual antiplatelet blood-thinning therapy (DAPT) compared to 12 months of treatment following the implant of a coronary stent.
The FDA is reviewing data from a Harvard Clinical Research Institute study presented at this week’s meeting of the American Heart Association and published in the New England Journal of Medicine. Early clinical trial data revealed that treatment with dual anti-platelet blood-thinning therapy – aspirin plus either clopidogrel (Plavix) or prasugrel (Effient) – for 30 months did decrease heart attack risks and the risk of clot formation in stents, a greater overall risk of death was seen when 30-month treatment was compared to a 12-month course of treatment. Clopidogrel and prasugrel are used to prevent heart attacks, strokes, and clot-related diseases. Medicine-coated stents are inserted into narrowed arteries in the heart to prop them open and maintain blood flow to the heart. The risks of stent thrombosis and heart attacks in the group receiving treatment for 30 months was reduced compared to 12-month treatment; however, there was a higher rate of death over all in the 30-month treatment group. The increased risk of death with longer treatment was seen in the patients taking clopidogrel, but not those given prasugrel.
The FDA said that at this time it is not recommending that doctors change the way they prescribe these drugs. Health Canada, Canada’s federal health regulatory agency, is also reviewing long-term DAPT safety concerns.