FDA Issues Safety Announcement On Long-Term Antiplatelet Therapy

Long-term antiplatelet therapy shows benefits but is also a risk for non-cardiovascular death, according to the Food and Drug Administration’s (FDAs) preliminary evaluation. The federal agency published its findings in a safety announcement, stating that a clinical trial showed that treatment with dual antiplatelet blood-thinning therapy for 30 months was associated with an increased overall risk of death compared to treatment for 12 months. The FDA stated that the benefits of the therapy still outweigh the risks and that patients should not discontinue treatment without consulting their healthcare provider.

In its announcement, the FDA stated it had not reviewed the trial’s results nor had it drawn conclusions. However, it is communicating the safety information while it evaluates the trial data. When it completes its review, the FDA said it will publish its conclusions. The results from the trial were published in a paper titled, “Twelve or 30 Months of Dual Antiplatelet Therapy after Drug-Eluting Stents,” in the New England Journal of Medicine (NEJM) on November 16, 2014.

Dual Antiplatelet Therapy

Dual antiplatelet therapy (DAPT) in the trial consisted of aspirin plus either clopidogrel (Plavix) or prasugrel (Effient). These medicines are used to prevent heart attacks, strokes, and other clot-related diseases. Dual antiplatelet therapy with aspirin and clopidogrel or prasugrel is the standard of care in many clinical scenarios, based on evidence from several clinical trials over the last 10 years. Investigators began the DAPT trial with the premise that the benefits and risks of treatment beyond one year were uncertain.

Dual Antiplatelet Therapy (DAPT) Trial

The DAPT study evaluated the optimal duration of antiplatelet therapy in approximately 10,000 patients after drug-eluting coronary stent placement. Investigators tested 12 months of therapy vs. 30 months of dual antiplatelet therapy. The results were mixed as the 30-month group showed reduced rates of stent thrombosis and heart attacks compared to the 12-month group. However, the 30-month group showed a higher rate of death. Those deaths were attributed to non-cardiovascular causes including cancer and trauma. Further refining the results, the increased rates of death were found in the clopidogrel group, but not the prasugrel group. The increased risk of death for clopidogrel has not been reported in previous large trials.