Compared with clopidogrel, ticagrelor inhibit platelet aggregation faster and stronger, and significantly reduce the risk of cardiovascular and cerebrovascular adverse events. In recent years, it has been given the strongest recommendation for antiplatelet therapy in ACS patients. Nevertheless, it was shown that excessive bleeding events significantly affect its antithrombotic advantage and better safety by downgrading regimen can seek more net clinical benefit. However, there are still huge controversies regarding the degree or timing of the downgrading regimen.
GLOBAL LEADERS study shortened the course of DAPT after PCI to 1 month in "all-comer" population of coronary heart disease , and then downgraded to ticagrelor monotherapy and continued 23 months. At 12 months, compared with standard DAPT, there was neither increased risk of thrombotic events, nor significant reduction in BARC3 or type 5 major bleeding events, which suggested satisfactory safety of 1-month DAPT, and relative insufficiency de-escalation. The most recent STOPDAPT-2 ACS study not only adapted 1-month DAPT (prasugrel or clopidogrel + aspirin) in ACS patients, but also directly downgraded to clopidogrel monotherapy. Compared with standard DAPT of clopidogrel + aspirin, clopidogrel monotherapy significantly reduces the risk of bleeding, however, it also increases the thrombotic risk. Overrall, the investigators believe that de-escalated antiplatelet therapy are most suitable in ACS patients undergoing PCI. Short-course DAPT based on potent P2Y12 inhibitors will not increase the thrombotic risk, but continuous application of one single P2Y12 receptor antagonists may be difficult to take into account both the antithrombotic efficacy and bleeding benefit, while the sequential monotherapy of ticagrelor and clopidogrel may be more conducive to balancing the two needs.
In summary, the current project aimed at"all-comer"population of ACS, for the first time proposed a de-escalated antiplatelet regimen of sequential monotherapy of ticagrelor and clopidogrel. In this project, ticagrelor monotherapy will be used 1 month after PCI, and the anti-platelet strength will be further downgraded 5 months later to clopidogrel (75 mg) monotherapy till 1 year, which is supposed to achieve a better safety benefit and a non-inferior efficacy.