P2Y12 inhibitor better than aspirin for patients with coronary artery disease: PANTHER
Barcelona, Spain: Patients with coronary artery disease (CAD) on P2Y12-inhibitor monotherapy were shown to have cardiovascular benefits compared with aspirin alone, according to findings from the PANTHER meta-analysis presented at the ESC Congress 2022 in Barcelona.
P2Y12 inhibitor monotherapy was tied to a lower risk of myocardial infarction (MI), stroke, and cardiovascular death versus aspirin monotherapy in CAD patients. The findings support a paradigm shift toward single P2Y12 inhibition for secondary prevention in the long-term antithrombotic management of CAD patients.
Currently, long-term antiplatelet therapy with aspirin is the linchpin for secondary prevention in patients with established atherosclerosis. Life-long aspirin is the standard of care following an initial course of dual antiplatelet therapy (DAPT) with a P2Y12 inhibitor plus aspirin in acute coronary syndrome patients or those undergoing percutaneous coronary intervention. The CAPRIE randomized trial found a significant, yet mild decrease in cardiovascular events with clopidogrel monotherapy versus h aspirin monotherapy in patients with coronary, cerebrovascular, and/or peripheral atherosclerosis. Studies that compared P2Y12 inhibitor monotherapy with clopidogrel or ticagrelor versus aspirin monotherapy have shown inconsistent results.
Against the above background, a research team led by Marco Valgimigli, the University Hospital of Bern, Switzerland aimed to address this uncertainty with the most comprehensive individual participant data meta-analysis to date of randomized controlled trials evaluating the effect of monotherapy with currently recommended oral P2Y12 inhibitors (clopidogrel, prasugrel, or ticagrelor) versus aspirin on adjudicated ischaemic and bleeding outcomes in patients with established coronary artery disease.
For the study, the researchers identified seven trials after a full-text review including 35,752 individual participants from 492 sites across Europe, Asia, and North America. The meta-analysis was conducted from seven trials -- ASCET, CADET, CAPRIE, DACAB, GLASSY, HOST-EXAM, and TiCAB. After exclusions, the final study population consisted of 24,325 patients, of whom 12,178 were assigned to P2Y12 inhibitor monotherapy (clopidogrel or ticagrelor) and 12,147 were assigned to aspirin monotherapy.
The median treatment duration of the patients was 557 days and the composite of cardiovascular death, myocardial infarction, and stroke were the pre-specified primary efficacy outcome. The pre-specified key secondary outcomes included net adverse clinical events (NACE) and major bleeding.
Based on the study, the researchers found the following:
- The study's primary outcome-the risk of cardiovascular death, myocardial infarction, and stroke-occurred in 5.5% of those on a P2Y12 inhibitor versus 6.3% of those on aspirin (HR 0.88).
- Major bleeding rates were similar between the P2Y12-inhibitor and aspirin groups (1.2% vs 1.4%, respectively).
- These two outcomes combined for a lower risk of net adverse clinical events (NACE) in the P2Y12-inhibitor group (6.4% vs 7.2%; HR 0.89), with a number needed to treat 121 to prevent one NACE with P2Y12 inhibitors.
"Based on available randomized evidence, long-term P2Y12 inhibitor monotherapy may be more warranted than long-term aspirin monotherapy for secondary prevention in patients with coronary artery disease," said Dr. Valgimigli, who presented the study findings.
Reference:
Valgimigli M, et al "PANTHER -- P2Y12 inhibitor versus aspirin monotherapy in patients with coronary artery disease" ESC 2022.
