Aspirin in Subclinical Coronary Artery Disease: A Pilot Randomised Controlled Trial (ASCAD-P)

In patients with subclinical coronary artery disease, the ASCAD-P study aims to assess the feasibility of a larger phase 3 pragmatic randomized controlled trial comparing prescription versus no prescription of low-dose aspirin in routine clinical practice.

Study Overview

• Status: Not yet recruiting
• Conditions: Coronary Artery Disease; Subclinical Atherosclerotic Cardiovascular Disease
• Intervention / Treatment: Drug: Prescription of Aspirin; Drug: No prescription

Detailed Description

Cardiovascular disease remains the leading cause of mortality worldwide. Recent large randomized trials have demonstrated limited net clinical benefit of aspirin in unselected primary prevention populations, leading to guideline recommendations against its systematic routine use for cardiovascular protection.

Patients with subclinical coronary artery disease represent a high-risk subgroup. These individuals have documented coronary artery disease but have not experienced overt cardiovascular events or undergone revascularization. Observational data suggest that this population carries a substantially increased risk of myocardial infarction compared with individuals without coronary atherosclerosis. However, the benefit-risk balance of aspirin in this intermediate-risk group remains uncertain

Primary Objective:

To evaluate the recruitment rate of a pilot randomized trial comparing low-dose aspirin prescription versus no prescription.

Secondary Objectives

To evaluate key feasibility metrics, including:

• The proportion of eligible patients who are randomized;
• Adherence and persistence to the assigned intervention at 12 months;
• The proportion of patients who do not complete the 12-month follow-up;
• Barriers to recruitment, adherence, and retention.

Exploratory Objectives:

To explore clinical outcomes at 12 months, including:

• The incidence of clinically significant bleeding events (BARC type 2, 3, or 5) and bleeding site;
• The incidence of major adverse cardiovascular events (MACE), defined as a composite of all-cause mortality, non-fatal myocardial infarction, non-fatal stroke, or coronary revascularization;
• Individual components of the composite endpoint;
• Cardiovascular mortality;
• Adverse Events and Serious Adverse Events.

• Study Type: Interventional
• Enrollment (Estimated): 48
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: Cyril Gagnon, MD; Phone Number: 2698 514-376-3330; Email: cyril.gagnon@umontreal.ca
• Study Contact Backup: Name: Samara Bloom, MSc; Phone Number: 2698 514-376-3330; Email: samara.bloom@icm-mhi.org

Study Locations

• Canada
  • Quebec
    • Montreal, Quebec, Canada, H1T 1C8
      • Montreal Heart Institute
      • Contact: Samara Bloom, BSc, MSc; Phone Number: 2698 514-376-3330; Email: Samara.Bloom@icm-mhi.org

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Documented coronary atherosclerosis, as defined by one of the following criteria:

   1. Coronary artery calcium (CAC) score > 0;
   2. Cardiac CT angiography (CCTA) / CoroScan: lesions <70% in the right coronary (RCA), left anterior descending (LAD), and circumflex (Cx) arteries or their branches, and <50% in the left main coronary artery;
   3. Coronary angiography: lesions <70% in the right coronary (RCA), left anterior descending (LAD), and circumflex (Cx) arteries or their branches, and <50% in the left main coronary artery; if performed, physiological coronary assessments (FFR, dPR, iFR, etc.) and intracoronary imaging (IVUS or OCT) must be negative for significant disease.
2. Willing and able to provide informed consent and comply with study procedures

Exclusion Criteria:

1. History of myocardial infarction (MI), coronary revascularization, stroke, transient ischemic attack (TIA), or peripheral arterial revascularization procedure;
2. Current prescription or clear indication for aspirin, low-molecular-weight heparin (LMWH), direct oral anticoagulants, or any other antithrombotic medication;
3. Clear contraindication to aspirin;
4. History of significant bleeding within the past year;
5. Severe illness with limited life expectancy (i.e., <5 years);
6. Any condition that, in the investigator's judgment, would make participation unsafe for the patient.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Low-dose Aspirin Prescription; Aspirin 81 mg orally once daily prescription	Drug: Prescription of Aspirin; Aspirin 81 mg orally once daily
Other: No Prescription; No prescription of aspirin 81 mg orally once daily	Drug: No prescription; No prescription of aspirin 81 mg orally once daily

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Monthly Recruitment Rate	Average monthly patient recruitment rate: 0 ≤ Mean rate (patients/month) < 2 = study not feasible; 2 ≤ Mean rate (patients/month) < 4 = study feasible with protocol modifications; ≥ 4 Mean rate (patients/month) = study feasible without major protocol modifications.	12 months following study enrollment initiation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of Eligible Patients Randomized	Proportion of eligible patients who are randomized: 0% ≤ Proportion < 30% = study not feasible, major protocol modifications required; 30% ≤ Proportion < 61% = study feasible with protocol modifications; ≥ 61% = study feasible without protocol modifications.	12 months following study enrollment initiation
Intervention Persistence	Proportion of patients who still take the assigned intervention at 12 months of follow-up (persistence): 0% ≤ Proportion < 25% = study not feasible, major protocol modifications required; 25% ≤ Proportion < 70% = study feasible with protocol modifications; ≥ 70% = study feasible without protocol modifications.	From randomization to end of follow-up (12 months)
Proportion of Patients Lost to Follow-up	Proportion of patients who do not complete the 12-month follow-up visit: ≥ 10% = study not feasible, major protocol modifications required; 6% ≤ Proportion < 10% = study feasible with protocol modifications; 0% ≤ Proportion < 6% = study feasible without protocol modifications.	End of follow-up (12 months)
Barriers to Recruitment, Adherence, and Patient Retention		From recruitment to the end of follow-up (12 months)
Intervention Adherence	Proportion of days on which patients take the assigned intervention (adherence): 0% ≤ Mean proportion < 25% = study not feasible, major protocol modifications required; 25% ≤ Mean proportion < 74% = study feasible with protocol modifications; ≥ 74% = study feasible without protocol modifications.	From randomization to the end of follow-up (12 months)

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Bleeding Rate (BARC 2, 3, 5)		From enrollment to the end of follow-up (12 months)
Major Adverse Cardiovascular Event (MACE) Rate	MACE rate (all-cause mortality, non-fatal myocardial infarction, non-fatal stroke, or coronary revascularization) at 12 months of follow-up	From enrollment to the end of follow-up (12 months)
Adverse Event (AE) Rate and Serious Adverse Event (SAE) Rate		From enrollment to the end of follow-up (12 months)

Collaborators and Investigators

• Sponsor: Montreal Heart Institute

Study record dates

Study Major Dates

• Study Start (Estimated): May 1, 2026
• Primary Completion (Estimated): May 1, 2027
• Study Completion (Estimated): May 1, 2028

Study Registration Dates

• First Submitted: April 5, 2026
• First Submitted That Met QC Criteria: April 5, 2026
• First Posted (Actual): April 13, 2026

Study Record Updates

• Last Update Posted (Actual): May 12, 2026
• Last Update Submitted That Met QC Criteria: May 7, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Aspirin; Coronary artery disease; Randomized; Bleeding; Clinical Trial; Antiplatelet; Major Adverse Cardiovascular Events; Prospective; Pilot Study; Pragmatic Trial; Feasability Study
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Coronary Disease; Myocardial Ischemia; Pathological Conditions, Signs and Symptoms; Coronary Artery Disease; Hemorrhage
• Other Study ID Numbers: 2026-3694

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No