Study on Ticagrelor vs Clopidogrel in ACS Patients Treated with PCI

A recent study published in the journal JAMA suggests that the use of ticagrelor over clopidogrel in ACS patients treated with PCI does not lead to better clinical outcomes.

Currently, ticagrelor is recommended as the preferred P2Y12 platelet inhibitor for acute coronary syndrome (ACS) patients. The recommendation is based primarily on a single large randomized clinical trial. There is a need for giving attention to the benefits and risks associated with ticagrelor vs clopidogrel in routine practice.

Seng Chan You, from Ajou University School of Medicine, Suwon, Korea, and colleagues aimed to determine the association of ticagrelor vs clopidogrel with ischemic and hemorrhagic events in patients undergoing percutaneous coronary intervention (PCI) for ACS in clinical practice.

For this purpose, the researchers conducted a retrospective cohort study of ACS patients who underwent PCI and received ticagrelor or clopidogrel. The study was conducted using two United States electronic health record–based databases and one nationwide South Korean database from November 2011 to March 2019. Patients were matched using a large-scale propensity score algorithm, and the date of final follow-up was March 2019.

They were randomized to receive either ticagrelor or clopidogrel. After propensity score matching among 31,290 propensity-matched pairs (median age group, 60-64 years; 29.3% women), 95.5% of patients took aspirin together with ticagrelor or clopidogrel.

The primary endpoint was net adverse clinical events (NACE) at 12 months, composed of ischemic events (recurrent myocardial infarction, revascularization, or ischemic stroke) and hemorrhagic events (hemorrhagic stroke or gastrointestinal bleeding).

Key Findings of the Study

• The 1-year risk of NACE was not significantly different between ticagrelor and clopidogrel (15.1% vs 14.6%; summary HR, 1.05).
• There was also no significant difference in the risk of all-cause mortality (2.0% for ticagrelor vs 2.1% for clopidogrel; summary HR, 0.97) or ischemic events (13.5% for ticagrelor vs 13.4% for clopidogrel; summary HR, 1.03).
• The risks of hemorrhagic events (2.1% for ticagrelor vs 1.6% for clopidogrel; summary HR, 1.35) and dyspnea (27.3% for ticagrelor vs 22.6% for clopidogrel; summary HR, 1.21) were significantly higher in the ticagrelor group.

"Our findings show that ticagrelor versus clopidogrel in ACS patients treated with PCI was not associated with a significant difference in the risk of NACE at 12 months. Because the possibility of unmeasured confounders cannot be excluded, further research is needed to determine whether ticagrelor is more effective than clopidogrel in this setting," concluded the authors.

The study, "Association of Ticagrelor vs Clopidogrel With Net Adverse Clinical Events in Patients With Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention," is published in the journal JAMA.

DOI: https://jamanetwork.com/journals/jama/fullarticle/2772280