51˶

Even in ACS, Early Aspirin Withdrawal Promising Post-PCI

— TWILIGHT drug regimen appears to balance safety, efficacy of medical therapy

MedpageToday

This article is a collaboration between 51˶ and:

PHILADELPHIA -- High-risk patients benefited from the withdrawal of aspirin from dual antiplatelet therapy (DAPT) a few months after stenting for non-ST-segment elevation acute coronary syndrome (ACS), a TWILIGHT substudy confirmed.

Rates of BARC (Bleeding Academic Research Consortium) 2, 3, or 5 bleeding were lower in the 12 months in people on ticagrelor (Brilinta) monotherapy compared with ticagrelor plus aspirin (3.6% vs 7.6%, HR 0.47, 95% CI 0.36-0.61), according to Usman Baber, MD, of Icahn School of Medicine at Mount Sinai in New York City.

This benefit was not offset by any apparent harm: the combined risk of death, myocardial infarction (MI), or stroke was comparable between groups (4.3% vs 4.4%, HR 0.97, 95% CI 0.74-1.28) and there was no difference in individual ischemic endpoints, Baber reported at the American Heart Association (AHA) meeting.

These subgroup findings were consistent no matter the number of high-risk clinical or angiographic features a patient had, or whether he or she presented with unstable angina or non-ST-segment elevation MI (NSTEMI), he added.

Thus, TWILIGHT-ACS reaffirms the September 2019 main TWILIGHT results of patients undergoing percutaneous coronary intervention (PCI) with drug-eluting stents who met one or more high-risk features.

GLOBAL LEADERS, SMART CHOICE, and STOPDAPT-2 are three studies that have similarly tested various strategies of aspirin discontinuation after 1 to 3 months of DAPT, said AHA discussant Michelle O'Donoghue, MD, MPH, of Brigham and Women's Hospital in Boston.

Pooling all four studies, she estimated that subsequent P2Y12 inhibitor monotherapy is associated with a 40% reduction in bleeding risk -- 50% in ACS patients -- with no uptick in major adverse cardiovascular events.

TWILIGHT investigators had enrolled 9,006 patients on DAPT with ticagrelor and aspirin, 7,119 of whom were adherent to their medications and event-free in the first 3 months post-PCI. Those patients were eligible for randomization to ticagrelor (90 mg twice daily) and either aspirin or placebo for the next 12 months.

Participants in TWILIGHT-ACS were the 4,614 people left from TWILIGHT after excluding people with stable angina. Ticagrelor monotherapy and DAPT arms were mostly comparable in their baseline characteristics (except there were more smokers in the latter).

The ACS subgroup commonly had three to five high-risk features.

Baber acknowledged the limited generalizability of the results to lower-risk people. Similarly, it's unknown if ticagrelor monotherapy is beneficial in groups excluded from TWILIGHT (such as STEMI patients and those with a need for chronic oral anticoagulation).

Furthermore, the trial was underpowered to evaluate between-group differences in rare events like stent thrombosis and stroke, he stated.

O'Donoghue noted that it's still unclear which P2Y12 inhibitor is the best choice for post-PCI monotherapy, and how long patients should continue their antithrombotic treatments.

  • author['full_name']

    Nicole Lou is a reporter for 51˶, where she covers cardiology news and other developments in medicine.

Disclosures

TWILIGHT was funded by AstraZeneca.

Baber disclosed relevant relationships with Amgen, AstraZeneca, and Boston Scientific, as well as institutional support from AstraZeneca.

O'Donoghue disclosed relevant relationships with Novartis, Janssen, and Amgen, as well as support from The Medicines Company, AstraZeneca, Eisai, Merck, and Amgen.

Primary Source

American Heart Association

Baber U, et al "Ticagrelor with aspirin or alone in high-risk patients after coronary intervention for acute coronary syndrome: TWILIGHT-ACS" AHA 2019.

Secondary Source

American Heart Association

O'Donoghue ML "Ticagrelor with aspirin or alone in high-risk patients after coronary intervention for ACS" AHA 2019.