Patients suffering from symptomatic carotid artery stenosis, transient ischemic attacks (TIAs), amaurosis fugax or stroke receive either Revacept (single dose) plus antiplatelet monotherapy or monotherapy alone.

Patients receive a single dose of trial medication by intravenous infusion for 20 minutes. Patients are followed up one and three days after treatment, at 3 months and by a telephone interview at 12 months.

Patients had a more than 50% carotid artery stenosis according to ECST and suffered from ischemic stroke, transitory ischemic attack or intermittent blindness (amaurosis fugax) within the last 30 days. All patients were on standard medication with aspirin or clopidogrel and received heparin for thrombosis prophylaxis. Carotid endarterectomy (CEA), carotid stenting (CAS) or best medical therapy for treatment of the carotid stenosis and prevention of secondary thrombo-emboli was performed according to guidelines. Additional treatment with Revacept or placebo was done on top of the standard therapy. Therefore the control group receiving placebo was already on the standard medical therapy for patients with symptomatic carotid stenosis and received also the guideline conform interventions CEA, CAS or best medical therapy.

Secondary prophylaxis of thrombo-embolic ischemic events by Revacept should be investigated. Therefore microemboli were detected by transcranial Doppler and ischemic brain lesions were investigated by diffusion weighted imaging magnetic resonance imaging (DWI-MRI) scan as exploratory endpoints. Moreover clinical endpoints such as stroke, TIA, myocardial infarction, coronary intervention and death were investigated at 1 week, 3 months and 12 months follow-up. Safety was closely monitored with emphasis on bleeding complications as bleeding is the most dreaded complication of anti-thrombotic agents especially in patients with cerebral strokes.

Inclusion Criteria:

1. Signed written informed consent

2. Target population

   • Diagnosis:

     • Extracranial carotid artery stenosis (diagnosed by vascular duplex ultrasound peak flow or angiography)
     • Lesions with ≥ 50 % stenosis according to the European Carotid Surgery Trial (ECST) criteria
     • TIA, amaurosis fugax or stroke within the last 30 days

   • Age and sex: Men and women aged > 18 years Women of childbearing potential (WOCBP) must be using an adequate method of contraception to avoid pregnancy throughout the study and for up to 4 weeks after receiving investigational product in such a manner that the risk of pregnancy is minimised.

Exclusion Criteria:

1. Sex and reproductive Status:

   • WOCBP who are unwilling or unable to use an acceptable method to avoid pregnancy for up to 4 weeks after receiving investigational product.
   • Women who are pregnant or breastfeeding
   • Women with a positive pregnancy test on enrollment or prior to investigational product administration.

2. Target disease exceptions

   • NIHSS score > 18
   • Recent intracerebral haemorrhage by X-ray computed tomography (CT) or nuclear magnetic resonance (NMR)
   • Cardiac cause of embolisation (atrial fibrillation or other cardiac source e.g. artificial heart valves)

3. Medical history and concurrent disease

   • History of hypersensitivity, contraindication or serious adverse reaction to inhibitors of platelet aggregation, hypersensitivity to related drugs (cross-allergy) or to any of the excipients in the study drug
   • History or evidence of thrombocytopenia (<30.000/ul), bleeding diathesis or coagulopathy (pathological international normalised ratio (INR) or activated partial thromboplastin time (aPTT))
   • Thrombolysis within the last 48 hours
   • Relevant haemorrhagic transformation as determined by CT, NMR or anamnesis
   • Oral anticoagulation or dual anti-platelet therapy with aspirin or clopidogrel and other P2Y inhibitors at screening (3 days for dipyridamole extended release; 8 hours for tirofiban/Aggrastat)
   • Sustained hypertension (systolic BP > 179 mmHg or diastolic BP >109 mmHg)
   • History of severe systemic disease such as terminal carcinoma, renal failure (or current creatinine > 200 umol/l), cirrhosis, severe dementia, or psychosis
   • Current severe liver dysfunction (transaminase level greater than 5-fold over upper normal range limit)
   • Active autoimmune disorder such as systemic lupus erythematosus, rheumatoid arthritis, vasculitis or glomerulonephritis
   • Known atrial fibrillation or other clinically significant ECG abnormalities (at present)

Adverse Event Data was gathered at a 3 month follow up visit in the clinic and up to one year by a telephone interview.

The study was originally planned as primary endpoint study for the evaluation of reduction of micro-embolic signals (MES) by transcranial Doppler (TCD). Therefore MES incidence was a key inclusion criteria at screening. Due to low incidence of MES in this patient population with high screening failure rate the mandatory presence of MES was abandoned during the course of the study. Consecutively the study was changed to an explorative study of the same protocol specified endpoints.