STOPDAPT-2
This study, led by Hirotoshi Watanabe, MD, of Kyoto University, and colleagues, followed a similar design, but with an even shorter duration of DAPT in the treatment arm, at 1 month, and stricter criteria for the stent, which was limited to one cobalt-chromium everolimus-eluting model (Xience Series; Abbott Vascular). During the first month of the trial, all patients received aspirin plus either clopidogrel or prasugrel; thereafter, patients in the 12-month group received aspirin and clopidogrel while the 1-month group was given clopidogrel alone.
The primary endpoint was a composite of cardiovascular and bleeding events, including MI, stent thrombosis, cardiovascular death, stroke, and major or minor bleeding. Secondary endpoints included these components individually, as well as a list of other cardiovascular and bleeding measures.
Similarly to the first trial, Dr. Watanabe and colleagues found that the shorter DAPT protocol was noninferior to standard DAPT and associated with a lower rate of bleeding events. The primary endpoint occurred in 2.4% of the 1-month DAPT group, compared with 3.7% of the 12-month DAPT group, thereby meeting noninferiority criteria (P less than .001). This finding was confirmed in the per-protocol population. The 1-month DAPT regimen was significantly associated with fewer major bleeding events than the 12-month protocol (0.41% vs. 1.54%), demonstrating superiority (P = .004). In addition, seven other measures of bleeding frequency were lower in the 1-month DAPT group than the standard DAPT group, including Bleeding Academic Research Consortium type 3 or 5 criteria, and Global Use of Strategies to Open Occluded Arteries moderate or severe criteria.
Dr. Watanabe and colleagues provided some insight into these findings and described clinical implications. “The benefit [of the 1-month DAPT regimen] was driven by a significant reduction of bleeding events without an increase in cardiovascular events,” they wrote. “Therefore, the very short DAPT duration of 1 month would be a potential option even in patients without high bleeding risk. Given the very low rates of stent thrombosis in studies using contemporary drug-eluting stents, avoiding bleeding with de-escalation of antiplatelet therapy may be more important than attempting further reduction of stent thrombosis with intensive antiplatelet therapy.”
SMART-CHOICE was funded by the Korean Society of Interventional Cardiology, Biotronik, Abbott Vascular, and Boston Scientific. Dr. Hahn and colleagues reported receiving additional financial relationships with AstraZeneca, Daiichi Sankyo, Sanofi-Aventis, and others. STOPDAPT-2 was funded by Abbott Vascular. Dr. Watanabe and colleagues reported receiving additional funding from Daiichi Sankyo, Otsuka Pharmaceutical, Kowa Pharmaceuticals, and others.
SOURCES: Watanabe H et al. JAMA. 2019 Jun 25. doi: 10.1001/jama.2019.8145; Hahn J-Y et al. JAMA. 2019 Jun 25. doi: 10.1001/jama.2019.8146.