The results of the STOP-DAPT 2 randomized controlled trial were presented by Dr. Hirotoshi Watanabe at the American College of Cardiology Annual Scientific Session (ACC 2019), at New Orleans, LA. According to the findings, 1-month DAPT was superior to 12-month DAPT in the prevention of net adverse ischemic events.
Drug-eluting stents (DESs) are currently used in the majority of percutaneous coronary intervention (PCI) procedures. On the other hand, the problems of the first-generation DES (late adverse events, such as very late stent thrombosis) have been pointed out. Dual antiplatelet therapy (DAPT) has become a standard regimen after DES implantation and for fear of very late stent thrombosis, DAPT is frequently performed for 1 year or longer in clinical practice. However, serious hemorrhagic complications associated with a prolonged DAPT duration can bring disadvantages to patients, and it is extremely important to clarify an optimal DAPT duration after DES procedure. Currently, 1-month DAPT regimen after bare metal stent (BMS) implantation is commonly used in clinical practice, producing no major problems. Based on a meta-analysis of recent clinical studies, it has also been reported that the use of Cobalt-Chromium Everolimus-Eluting Stent (CoCr-EES) reduces the risk of early stent thrombosis by half compared to the use of BMS. There is no necessity to extend antiplatelet therapy after CoCr-EES implantation longer than after BMS implantation, and it is considered possible to use the same 1-month DAPT duration as after BMS implantation.
[perfectpullquote align=”full” bordertop=”false” cite=”” link=”” color=”” class=”” size=””]“Among patients undergoing PCI for stable and unstable cardiovascular disease, 1-month DAPT followed by clopidogrel monotherapy is superior to 12-month DAPT followed by aspirin monotherapy at preventing net adverse clinical events. One-month DAPT is non-inferior to 12-month DAPT at preventing major adverse ischemic events and superior to 12-months DAPT at preventing TIMI major/minor bleeding. BARC 3 or 5 bleeding is low, but 1-month DAPT is also associated with a reduction in this outcome compared with 12-month DAPT.”- Dr. Hirotoshi Watanabe, M.D.[/perfectpullquote]
Therefore, the investigators of STOPDAPT-2 planned a multicenter, randomized, open-label, controlled study, in which the subjects who have undergone CoCr-EES procedure would be divided into the 1-month DAPT and clopidogrel monotherapy group and the 12-month DAPT and aspirin monotherapy group. The design of this trial is was similar to the GLOBAL LEADERS trial. The primary endpoint was the incidence of composite events including cardiovascular death, myocardial infarction, stent thrombosis, stroke, and bleeding defined by TIMI major or minor bleeding. The goal of the trial comprising of 3045 enrollees was to evaluate 1-month dual antiplatelet therapy (DAPT) compared with 12-month DAPT among patients undergoing percutaneous coronary intervention (PCI). At first, the non-inferiority about the primary endpoint of 1-month DAPT group would be evaluated at 12 months after index procedure and secondarily, the superiority about the primary endpoint of 1-month DAPT group would be evaluated at 5 years after the index procedure. Patients undergoing PCI were randomized to 1 month of DAPT followed by clopidogrel monotherapy for 5 years (n = 1,523) versus 12 months of DAPT followed by aspirin monotherapy for 5 years (n = 1,522).
The STOPDAPT-2 investigators concluded that the primary outcome of death, myocardial infarction (MI), stent thrombosis, stroke, TIMI major/minor bleeding at 1 year, occurred in 2.4% of the 1-month DAPT group compared with 3.7% of the 12-month DAPT group (p for superiority = 0.04). Moreover, there was evidence of possible treatment interaction favoring 12 months of DAPT among those with chronic kidney disease. The rates of death, MI, stent thrombosis, or stroke at 1 year were 2.0% of 1-month DAPT group compared with 2.5% of 12-month DAPT group (p for non-inferiority = 0.005). The rate of TIMI major/minor bleeding at 1 year was 0.4% of 1-month DAPT group compared with 1.5% of 12-month DAPT group (p for superiority = 0.004). Additionally, Bleeding Academic Research Consortium (BARC) 3 or 5 bleeding at 1 year was 0.5% of 1-month DAPT group as compared with 1.8% of 12-month DAPT group (p for superiority = 0.003). Summarizing the take-home message, investigator Dr. Hirotoshi Watanabe stated, “Among patients undergoing PCI for stable and unstable cardiovascular disease, 1-month DAPT followed by clopidogrel monotherapy is superior to 12-month DAPT followed by aspirin monotherapy at preventing net adverse clinical events. One-month DAPT is non-inferior to 12-month DAPT at preventing major adverse ischemic events and superior to 12-months DAPT at preventing TIMI major/minor bleeding. BARC 3 or 5 bleeding is low, but 1-month DAPT is also associated with a reduction in this outcome compared with 12-month DAPT.”
To watch the interview with Dr. Hirotoshi Watanabe, click here.