For Clinicians

Scientific Summary

 

The DAPT study will assess the benefits of 12 versus 30 months of dual antiplatelet therapy for preventing stent thrombosis and major adverse cardiovascular and cerebrovascular events (MACCE) in subjects undergoing percutaneous coronary intervention (PCI) with drug-eluting stent placement for the treatment of coronary artery lesions. The DAPT Study aims to address three areas of equipoise:

• In consideration of the need to balance the benefit of clot prevention with bleeding risk, is it better to continue dual antiplatelet therapy for longer than one year?
• If so, is this benefit specific to DES or to a more general population of stent patients?
• Is the benefit mediated by prevention of stent thrombosis or is there a global reduction in cardiovascular risk?

The trial will be a four-year, prospective, randomized, double-blind trial that is expected to enroll over 15,000 subjects being treated with a drug-eluting stent (DES) at over 200 sites in the U.S., E.U., Australia and New Zealand. A cohort of approximately 5,000 subjects treated with a bare metal stent (BMS) will also be enrolled.

All subjects will receive 12 months of open-label thienopyridine/antiplatelet treatment in addition to aspirin. After 12 months, subjects who are free from all MACCE or major bleeding events will be randomized 1:1 to either placebo or ongoing dual antiplatelet therapy for an additional 18 months, followed by three months of observational follow-up. Both arms will continue aspirin therapy. The choice of stent type and thienopyridine drug will be at the discretion of the patient and physician.

The co-primary endpoints for this trial are: 1) the incidence of the composite of all death, myocardial infarction (MI) and stroke between 12 and 33 months post-drug-eluting stent procedure, and 2) the incidence of stent thrombosis between 12 and 33 months post-stent procedure. The primary safety endpoint for this trial is incidence of major bleeding between 12 and 33 months post-drug-eluting stent procedure. The study will also include an adjusted comparison of patients treated with BMS compared with DES on varying durations of antiplatelet therapy.