Study duration: 90 days
Study drugs: Aspirin vs aspirin & 75mg clopidogrel QD (600mg/placebo loading dose; 81mg ASA site prescription)
- Neurologic deficit (based on history or exam) attributed to focal brain ischemia and EITHER:
- High risk TIA: Complete resolution of the deficit at the time of randomization AND ABCD2 score >4
- Minor ischemic stroke: residual deficit with NIHSS <3 at the time of randomization
- Ability to randomize within 12 hours of time last known free of new ischemic symptoms.
- Head CT or MRI ruling out hemorrhage or other pathology (i.e. vascular malformation, tumor, or abscess).
- Ability to tolerate aspirin at a dose of 50-325 mg/day.
- Age <18 years.
- TIA symptoms limited to isolated numbness, isolated visual changes, or isolated dizziness/vertigo.
- A candidate for thrombolysis, endarterectomy or endovascular intervention, unless the subject declines both endarterectomy and endovascular intervention at the time of evaluation for eligibility.
- Receipt of any intravenous or intra-arterial thrombolysis within 1 week prior to index event.
- Gastrointestinal bleed or major surgery within 3 months prior to index event.
- History of nontraumatic intracranial hemorrhage.
- Clear indication for anticoagulation (e.g., warfarin, heparin) such as atrial fibrillation, mechanical heart valve, deep venous thrombosis, pulmonary embolism, antiphospholipid antibody syndrome, hypercoagulable state.
- Qualifying ischemic event induced by angiography or surgery.
- Severe non-cardiovascular comorbidity with life expectancy <3 months.
- Contraindication to clopidogrel or aspirin:
- Known allergy
- Severe renal (serum creatinine >2 mg/dL) or hepatic insufficiency (prior or concurrent diagnosis, with INR>1.5, or any resultant complication, such as variceal bleeding, encephalopathy, or icterus)
- Hemostatic disorder or systemic bleeding in the past 3 months
- Current thrombocytopenia (platelet count <100 x109/l) or neutropenia/granulocytopenia (<1 x109/l)
- History of drug-induced hematologic or hepatic abnormalities
- Anticipated requirement for long-term (>7 day) non-study antiplatelet drugs (e.g., dipyridamole, clopidogrel, ticlopidine), or NSAIDs affecting platelet function (such as prior vascular stent or arthritis).
- At risk for pregnancy: premenopausal or post menopausal woman within 12 months of last menses without a negative pregnancy test or not committing to adequate birth control (e.g., oral contraceptive, two methods of barrier birth control, or abstinence).
- Ongoing treatment in another study of an investigational therapy, or treatment in such a study within the last 7 days. (and previous POINT study patient)