Short DAPT Followed by Clopidogrel monotherapy No Better Than Long term DAPT: JAMA

A recent study suggests that clopidogrel monotherapy after 1 to 2 months of DAPT is no better than standard 12 months of DAPT among ACS patients with successful PCI. The study findings were published in the JAMA Cardiology today (March 02, 2022).

Previous studies have demonstrated the superiority of ticagrelor and prasugrel over clopidogrel in the ACS setting. However, the use of clopidogrel remains high across the globe. Also, clopidogrel monotherapy after very short DAPT has not yet been fully investigated in patients with ACS. Therefore, Dr Hirotoshi Watanabe and his team conducted a non-inferiority study and compared the 1 to 2 months of DAPT with 12 months of DAPT for a composite endpoint of cardiovascular and bleeding events in patients with ACS.

The STOPDAPT-2 (Short and Optimal Duration of Dual Antiplatelet Therapy After Everolimus-Eluting Cobalt-Chromium Stent-2) was a multicenter, open-label, randomized study. The researchers included 4169 patients with ACS who underwent successful PCI using cobalt-chromium everolimus-eluting stents at 96 centres in Japan. They randomized the patients either to 1 to 2 months of DAPT followed by clopidogrel monotherapy (n = 2078) or to 12 months of DAPT with aspirin and clopidogrel (n = 2091). Among 4169 patients, 4107 (99.3%) completed the 1-year follow-up in June 2021.

The primary endpoints assessed were a composite of cardiovascular (cardiovascular death, myocardial infarction [MI], any stroke, or definite stent thrombosis) or bleeding (Thrombolysis in MI major or minor bleeding) events at 12 months, with a noninferiority margin of 50% on the hazard ratio (HR) scale. Secondary endpoints assessed were cardiovascular and bleeding components of the primary endpoint.

Key findings of the study:

• The researchers noted that the primary endpoint occurred in 65 of 2058 patients (3.2%) in the 1- to 2-month DAPT group and in 58 of 2057 patients (2.8%) in the 12-month DAPT group. They observed that one to 2 months of DAPT was not non-inferior to 12 months of DAPT for the primary endpoint (absolute difference, 0.37%; HR, 1.14 ; P for noninferiority = .06).
• They observed that the major secondary cardiovascular endpoint occurred in 56 patients (2.8%) in the 1- to 2-month DAPT group and in 38 patients (1.9%) in the 12-month DAPT group (absolute difference, 0.90%]; HR, 1.50).
• They further noted that the major secondary bleeding endpoint occurred in 11 patients (0.5%) in the 1- to 2-month DAPT group and 24 patients (1.2%) in the 12-month DAPT group (absolute difference, −0.63%; HR, 0.46).

The authors concluded, " In patients with ACS with successful PCI, clopidogrel monotherapy after 1 to 2 months of DAPT failed to attest noninferiority to standard 12 months of DAPT for the net clinical benefit with a numerical increase in cardiovascular events despite reduction in bleeding events. The directionally different efficacy and safety outcomes indicate the need for further clinical trials."

For further information:

DOI: 10.1001/jamacardio.2021.5244