Overview
This is a randomized, open-label, active-controlled, non-inferiority clinical trial (the ASPIRE-LD trial) conducted in China. It aims to compare the efficacy and safety of low-dose aspirin (50 mg once daily) versus standard-dose aspirin (100 mg once daily), both in combination with a P2Y12 inhibitor, in patients who have successfully undergone percutaneous coronary intervention (PCI) and plan to receive at least 12 months of dual antiplatelet therapy (DAPT).
A total of 2640 eligible patients will be randomly assigned in a 1:1 ratio to receive either 50 mg or 100 mg of enteric-coated aspirin daily, plus a P2Y12 inhibitor (ticagrelor 90 mg twice daily or clopidogrel 75 mg once daily, prescribed according to routine clinical practice). All participants will be followed for 12 months after randomization.
The primary goal is to verify that 50 mg aspirin is non-inferior to the 100 mg standard dose in preventing major adverse cardiac and cerebrovascular events (MACCE: cardiovascular death, non-fatal myocardial infarction, definite/probable stent thrombosis, and ischemic stroke) at 12 months post-PCI. If non-inferiority is confirmed, the study will further test whether 50 mg aspirin reduces clinically relevant bleeding events (BARC type 2, 3, or 5) better than the standard dose.
The study is sponsored by the First Hospital of Jilin University and will be carried out in 10-15 tertiary hospitals across China. Its findings will provide evidence for optimizing aspirin dosing in post-PCI DAPT.
Description
Background Dual antiplatelet therapy (DAPT) - aspirin combined with a P2Y12 inhibitor - is the standard of care to prevent stent thrombosis and ischemic events after PCI. However, the optimal aspirin dose in combination with modern P2Y12 inhibitors remains undefined, especially in Chinese populations. Current practice widely uses 100 mg daily aspirin, but pharmacological and clinical evidence suggests that lower doses may achieve comparable antiplatelet effect with a lower bleeding risk.
Study Design This is a multicenter, randomized, open-label, active parallel-controlled non-inferiority trial. Enrollment will include 2640 adults with acute or chronic coronary syndrome who have undergone successful PCI and are scheduled for at least 12 months of DAPT. Randomization will be stratified by study center with a 1:1 allocation ratio.
Treatment Regimens
- Experimental group: enteric-coated aspirin 50 mg once daily + a P2Y12 inhibitor
- Control group: enteric-coated aspirin 100 mg once daily + a P2Y12 inhibitor The choice of P2Y12 inhibitor (ticagrelor or clopidogrel) is at the treating physician's discretion based on patient characteristics and clinical guidelines. DAPT will be maintained for a minimum of 12 months.
Outcome Assessment All suspected endpoint events will be independently adjudicated by a blinded Clinical Endpoint Committee according to standardized international definitions. A Data Monitoring Committee will periodically review safety data and study conduct.
Follow-up visits are scheduled at 1 month, 6 months, and 12 months after randomization, including clinical assessment, medication adherence evaluation, and event verification.
Eligibility
Inclusion Criteria:
- Aged 18 to 85 years at the time of screening
- Diagnosed with acute coronary syndrome (ACS) or chronic coronary syndrome (CCS)
- Has undergone successful percutaneous coronary intervention (PCI) with stent implantation
- Planned to receive at least 12 months of dual antiplatelet therapy (DAPT) with aspirin plus a P2Y12 inhibitor after PCI
- Able to provide written informed consent and comply with study follow-up requirements
Exclusion Criteria:
- Known hypersensitivity or contraindication to aspirin, P2Y12 inhibitors, or related excipients
- High bleeding risk: history of intracranial hemorrhage, gastrointestinal bleeding within 6 months, active bleeding diathesis, or coagulopathy
- Severe hepatic dysfunction (Child-Pugh class C) or severe renal impairment (eGFR \< 30 mL/min/1.73 m²)
- Ischemic or hemorrhagic stroke within 3 months before enrollment
- Pregnant or lactating women; women of childbearing potential unwilling to use effective contraception
- Life expectancy \< 12 months due to other severe comorbidities such as advanced malignancy
- Participation in another interventional clinical trial within 30 days before screening
- Any other condition judged by the investigator to make the patient unsuitable for the study
