Real-world implementation of a genotype-guided p2y12-inhibitor de-escalation strategy in acute coronary syndrome patients

Background CYP2C19 genotype-guided de-escalation from ticagrelor or prasugrel to clopidogrel, may optimize the balance between ischemic and bleeding risk in ACS patients. Purpose Compare bleeding and ischemic event rates in genotyped patients versus standard care. Methods Since 2015, ACS patients in the FORCE-ACS registry received standard dual antiplatelet therapy (DAPT). Since 2021, immediate genotype-guided P2Y12-inhibitor de-escalation was applied, switching non-carriers of the loss-of-function allele CYP2C19*3 or CYP2C19*2 from ticagrelor or prasugrel to clopidogrel, while loss-of-function carriers, carrying at least one loss-of-function allele, remained on ticagrelor or prasugrel. The primary ischemic endpoint, a composite of cardiovascular mortality, myocardial infarction (MI) or stroke and the primary bleeding endpoint, BARC 2, 3, or 5 bleeding, were compared between genotyped those on standard DAPT after one year. Results Among 5,321 enrolled ACS patients, 406 underwent genotyping, compared with 4,915 non-genotyped ACS patients on standard DAPT. In the genotyped cohort, 65.3% (n=265) were non-carriers, whereas 34.7% (n=141) were loss-of-function carriers. The primary ischemic endpoint occurred in 5.2% of patients in the genotyped cohort compared to 6.9% in the standard care cohort (adjHR 0.88, 95% CI 0.56–1.38). The rate of the primary bleeding endpoint was lower in the genotyped cohort compared to the standard care cohort (4.7% vs. 9.8%; adjHR 0.50, 95% CI 0.31-0.78). Conclusion These results demonstrate the feasibility of a CYP2C19 genotype-guided P2Y12-inhibitor de-escalation strategy in a real-world ACS population. This strategy reduced bleeding events, while ischemic events were not increased as compared to a standard DAPT regime.