Discontinuing aspirin was beneficial to prevent ischemic events and reduce bleeding in patients with the acute coronary syndrome (ACS) in dual antiplatelet therapy (DAPT), local researchers said in a paper.

DAPT is a standard therapy using aspirin with ticagrelor (P2Y12 inhibitor) for ACS patients to prevent ischemic events after percutaneous coronary intervention (PCI) stenting.

Severance Hospital Cardiology Professor Jang Yang-soo released the results of the investigator-initiated TICO (Ticagrelor With or Without Aspirin in Acute Coronary Syndrome After PCI) trial on 3,056 patients with ACS, at the virtual meeting of the World Congress of Cardiology hosted by the American College of Cardiology (ACC.20/WCC) on Monday.

The study compared the DAPT of aspirin and ticagrelor combo with ticagrelor alone.

The research team divided patients under three months of DAPT treatment into two groups – one maintained DAPT and the other excluded aspirin. Then, the researchers evaluated the net adverse clinical event (NACE) rate at 12 months. NACE was defined as a combined occurrence of thrombolysis in myocardial infarction (TIMI) major bleeding and all-cause death, myocardial infarction, stent thrombosis, stroke or target vessel revascularization.

The findings showed that patients with ticagrelor alone had a 3.9 percent NACE rate at 12 months, whereas those who maintained DAPT showed a 5.9 percent NACE rate. Using ticagrelor without aspirin reduced the risk of ischemic events and bleeding by 34 percent.

After the TICO trial presentation, the ACC conducted a phone interview with Jang to share the background, design, and results of the study on the internet.

In an email interview with Korea Biomedical Review, Jang said the TICO trial results are expected to bring changes to the treatment of ACS patients.

Physicians have used DAPT as the standard therapy, using two antiplatelet agents such as aspirin and P2Y12 inhibitor, for at least six to 12 months to prevent ischemic events such as stent thrombosis or recurrence of acute myocardial infarction after PCI in ACS patients.

However, Jang explained that using two antiplatelet agents could raise the risk of bleeding, despite the benefit of preventing ischemic events.

“While international guidelines recommend using strong P2Y12 inhibitors like prasugrel or ticagrelor with aspirin, such therapy raises the chance of bleeding for Koreans,” he said. “The increased bleeding events were thought to have been affected by ticagrelor or prasugrel. However, this study confirmed that discontinuation of aspirin early lowered the bleeding risk significantly.”

Cutting aspirin early in women could also be effective, but it needs further research, Professor Jang added.