In the STOPDAPT-2 ACS trial (NCT03462498), ischemic events (especially myocardial infarction) was significantly increased with 1-month DAPT followed by clopidogrel monotherapy, as compared to 12-month DAPT in patients with acute coronary syndrome (ACS). This was potentially attributable to clopidogrel, instead of prasugrel, which is more potent and has less individual difference in efficacy. On the other hand, previous studies including the STOPDAPT-2 ACS that evaluated the safety and efficacy of monotherapy with a P2Y12 inhibitor without aspirin consistently and significantly reduced the risk of bleeding, compared with standard DAPT. Consequently, there has been growing necessity to establish the safety with P2Y12 inhibitor monotherapy in terms of major adverse cardiovascular events. Therefore, we have planned to evaluate the non-inferiority of P2Y12 inhibitor monotherapy with prasugrel versus standard 12-month DAPT with prasugrel and aspirin in terms of the incidence of major cardiovascular events at 12 months after primary PCI in patients with STEMI using Platinum-Chromium Everolimus Eluting Stent (PtCr-EES; SYNERGYTM).
The aim of this study is to evaluate the safety of prasugrel monotherapy without aspirin versus 12-month dual antiplatelet therapy (DAPT) in patients with STEMI using platinum-chrome everolimus-eluting stent (PtCr-EES: SYNERGYTM).