Clopidogrel plus aspirin after thrombectomy or IV thrombolysis for acute ischemic stroke

Clopidogrel Plus Aspirin in Acute Ischemic Stroke Following Thrombectomy and/or Intravenous Thrombolysis (CoPrime): A Randomized Pilot Study

This trial tests whether adding clopidogrel to aspirin shortly after clot-removal or clot-busting treatment can reduce early repeat strokes in adults with mild-to-moderate acute ischemic stroke.

Quick facts

• Phase: PHASE2
• Study type: Interventional
• Enrollment: 200 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: University of Alberta (other)
• Locations: 1 site (Edmonton, Alberta)
• Trial ID: NCT06638151 on ClinicalTrials.gov

What this trial studies

This Phase 2 interventional trial enrolls adults with non-cardioembolic anterior circulation ischemic stroke who received reperfusion therapy (intravenous thrombolysis and/or endovascular thrombectomy) and have no post-procedure hemorrhage on CT. Eligible participants with mild-to-moderate deficits (NIHSS ≤11) and premorbid mRS ≤2 are randomized within 24 hours after reperfusion to receive either aspirin alone or aspirin plus clopidogrel. The trial compares the two antiplatelet regimens to see if dual therapy reduces early recurrent ischemic events without excess bleeding. Imaging and clinical criteria (including ASPECTS ≥8 on post-reperfusion CT) are used to screen safety for enrollment.

Who should consider this trial

Good fit: Adults over 18 with a non-cardioembolic anterior circulation ischemic stroke treated with IV thrombolysis and/or thrombectomy, randomized within 24 hours, NIHSS ≤11, no hemorrhage on post-reperfusion CT, and premorbid mRS ≤2 are the ideal candidates.

Not a fit: Patients with cardioembolic strokes, a known high bleeding risk, need for therapeutic anticoagulation, post-reperfusion hemorrhage or ASPECTS <8, or other contraindications to antiplatelet therapy are unlikely to benefit from this approach.

Why it matters

Potential benefit: If successful, adding clopidogrel to aspirin could lower the risk of early recurrent ischemic stroke after reperfusion therapy compared with aspirin alone.

How similar studies have performed: Previous trials (e.g., CHANCE, POINT) showed short-course clopidogrel plus aspirin reduces early recurrent stroke in minor stroke/TIA populations, but this combination is less studied specifically after reperfusion therapies like thrombectomy or thrombolysis.

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

Where this trial is running

Edmonton, Alberta

• University of Alberta Hospital — Edmonton, Alberta, Canada (RECRUITING)

Study contacts

• Principal investigator: Brian Buck — University of Alberta
• Study coordinator: Emily Sugars

Conditions: Acute Ischemic Stroke, intravenous thrombolysis, endovascular thrombectomy, recurrent stroke, Anti-platelet Medication, Aspirin, Clopidogrel, Acute ischemic stroke