Prasugrel-based de-escalation of dual antiplatelet therapy after percutaneous coronary intervention in patients with acute coronary syndrome (HOST-REDUCE-POLYTECH-ACS): an open-label, multicentre, non-inferiority randomised trial.

BACKGROUND: A potent P2Y12 inhibitor-based dual antiplatelet therapy is recommended for up to 1 year in patients with acute coronary syndrome receiving percutaneous coronary intervention (PCI). The greatest benefit of the potent agent is during the early phase, whereas the risk of excess bleeding continues in the chronic maintenance phase. Therefore, de-escalation of antiplatelet therapy might achieve an optimal balance between ischaemia and bleeding. We aimed to investigate the safety and efficacy of a prasugrel-based dose de-escalation therapy. METHODS: HOST-REDUCE-POLYTECH-ACS is a randomised, open-label, multicentre, non-inferiority trial done at 35 hospitals in South Korea. We enrolled patients with acute coronary syndrome receiving PCI. Patients meeting the core indication for prasugrel were randomly assigned (1:1) to the de-escalation group or conventional group using a web-based randomisation system. The assessors were masked to the treatment allocation. After 1 month of treatment with 10 mg prasugrel plus 100 mg aspirin daily, the de-escalation group received 5 mg prasugrel, while the conventional group continued to receive 10 mg. The primary endpoint was net adverse clinical events (all-cause death, non-fatal myocardial infarction, stent thrombosis, repeat revascularisation, stroke, and bleeding events of grade 2 or higher according to Bleeding Academic Research Consortium [BARC] criteria) at 1 year. The absolute non-inferiority margin for the primary endpoint was 2·5%. The key secondary endpoints were efficacy outcomes (cardiovascular death, myocardial infarction, stent thrombosis, and ischaemic stroke) and safety outcomes (bleeding events of BARC grade ≥2). The primary analysis was in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02193971. RESULTS: From Sept 30, 2014, to Dec 18, 2018, 3429 patients were screened, of whom 1075 patients did not meet the core indication for prasugrel and 16 were excluded due to randomisation error. 2338 patients were randomly assigned to the de-escalation group (n=1170) or the conventional group (n=1168). The primary endpoint occurred in 82 patients (Kaplan-Meier estimate 7·2%) in the de-escalation group and 116 patients (10·1%) in the conventional group (absolute risk difference -2·9%, pnon-inferiority<0·0001; hazard ratio 0·70 [95% CI 0·52-0·92], pequivalence=0·012). There was no increase in ischaemic risk in the de-escalation group compared with the conventional group (0·76 [0·40-1·45]; p=0·40), and the risk of bleeding events was significantly decreased (0·48 [0·32-0·73]; p=0·0007). INTERPRETATION: In east Asian patients with acute coronary syndrome patients receiving PCI, a prasugrel-based dose de-escalation strategy from 1 month after PCI reduced the risk of net clinical outcomes up to 1 year, mainly driven by a reduction in bleeding without an increase in ischaemia. FUNDING: Daiichi Sankyo, Boston Scientific, Terumo, Biotronik, Qualitech Korea, and Dio.