Clopidogrel Plus Aspirin in Acute Ischemic Stroke Following Thrombectomy and/or Intravenous Thrombolysis (CoPrime)

NCT ID: NCT06638151

Last Updated: 2025-09-09

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: PHASE2
• Total Enrollment: 200 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-09-02
• Study Completion Date: 2027-03-31

Brief Summary

Stroke is a common cause of disability. The most common type of stroke, an ischemic stroke, is caused by a blood vessel in the brain getting blocked by a clot. When this happens, part of the brain is damaged because it is not getting the blood supply it needs. To treat this type of stroke, doctors give medication and/or do a procedure to remove the blockage and restore blood supply to the brain.

Unfortunately, patients who have had an ischemic stroke are at higher risk of having another ischemic stroke. This risk is highest in the first 21 days after a stroke. Currently, doctors give patients the medication aspirin every day, starting 24 hours after stroke treatment, to prevent recurrent strokes. However, some studies have shown that giving another medication, clopidogrel, in addition to aspirin, is safe and may work better than aspirin alone at preventing repeat strokes. Both aspirin and clopidogrel are a type of medication called an antiplatelet that prevents clots from forming in the blood. When both medications are given together, it is called dual antiplatelet treatment. The main risk of antiplatelet medications is bleeding.

This research aims to study the safety and feasibility of using dual antiplatelet treatment to prevent recurrent strokes. Patients who have received treatment for an ischemic stroke will first be screened to rule out patients at high risk of bleeding. Following informed consent, patients at low risk of bleeding will be enrolled in the study 24 hours after their initial stroke treatment. Patients will be randomly assigned to either take aspirin alone or aspirin and clopidogrel for 21 days for recurrent stroke prevention. The study team will then follow patients for three months after treatment to collect information about their recovery and assess differences between the two groups.

Conditions

Acute Ischemic Stroke

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Aspirin Group

Group Type: ACTIVE_COMPARATOR

Aspirin

Intervention Type: DRUG

Aspirin 81 mg once daily alone

Dual Antiplatelet Group

Group Type: EXPERIMENTAL

aspirin + clopidogrel

Intervention Type: DRUG

Enrolled patients with acute ischemic stroke will be randomly assigned to the clopidogrel plus aspirin group (300 mg loading dose of clopidogrel plus 160 mg aspirin on day 1; followed by clopidogrel 75 mg plus aspirin 81 mg daily from day 2-day 21, followed by aspirin 81 mg to be continued if no alternate treatment is indicated).

Interventions

aspirin + clopidogrel

Enrolled patients with acute ischemic stroke will be randomly assigned to the clopidogrel plus aspirin group (300 mg loading dose of clopidogrel plus 160 mg aspirin on day 1; followed by clopidogrel 75 mg plus aspirin 81 mg daily from day 2-day 21, followed by aspirin 81 mg to be continued if no alternate treatment is indicated).

Intervention Type: DRUG

Aspirin

Aspirin 81 mg once daily alone

Intervention Type: DRUG

Other Intervention Names

Dual antiplatelet treatment

Eligibility Criteria

Inclusion Criteria

1. Participants must be >18 years of age at the time of randomization

2. Acute non-cardioembolic ischemic stroke in the anterior circulation treated with reperfusion therapy defined as intravenous thrombolysis (IVT) and/or endovascular thrombectomy (EVT)

3. Time from end of acute reperfusion therapy to randomization ≤ 24 hours

4. Mild to moderate deficit defined as a National Institute of Health stroke scale of ≤11 at the time of randomization

5. At least one non-contrast CT scan completed post reperfusion therapy and prior to randomization without any hemorrhage (including hemorrhagic infarction) and/or contrast extravasation.

6. Premorbid mRS less than or equal to 2

7. Signed informed consent from the patient or legally authorized representative

Exclusion Criteria

1. Any known disorder associated with a significantly increased risk of bleeding

2. Post-reperfusion CT scan ASPECT score <8.

3. Anticoagulation is required for any indication other than DVT prophylaxis

4. Evidence-based indication for dual antiplatelet therapy

5. Planned surgical intervention in the next 90 days includes but is not limited to carotid endarterectomy, where dual antiplatelet is not indicated, and carotid stenting, where single antiplatelet is not used.

6. History of intracranial or subarachnoid hemorrhage

7. Intracranial tumour, arteriovenous malformation or aneurysm;

8. Intracranial or spinal cord surgery within three months;

9. Gastrointestinal or urinary tract hemorrhage within the previous 21 days;

10. Coagulation disorder, thrombocytopenia <100, 000/mm3, and Prothrombin time INR ≥1.8

11. Index stroke is caused by infective endocarditis, dissection, systematic or central nervous system vasculitis

12. History of active malignancy being treated or life expectancy ≤ 90 days

13. Allergy to clopidogrel or aspirin

14. Pregnancy

15. Participation in another clinical trial.

16. The presence of a major co-morbid illness that would make it unlikely that the participant will be able to complete follow-up

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University of Alberta

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Brian Buck

Role: PRINCIPAL_INVESTIGATOR

University of Alberta

Mahesh Kate

Role: PRINCIPAL_INVESTIGATOR

University of Alberta

Locations

University of Alberta Hospital

Edmonton, Alberta, Canada

Site Status: RECRUITING

Countries

Canada

Central Contacts

Emily Sugars

Role: CONTACT

esugars@ualberta.ca

7804074366

Facility Contacts

Paige Fairall

Role: primary

fairall@ualberta.ca

7804074366

Other Identifiers

Pro00140876

Identifier Type: -

Identifier Source: org_study_id