Safety and Efficacy Study of a Protease Activated Receptor-4 Antagonist Being Tested to Reduce the Chances of Having Additional Strokes or "Mini Strokes"

For more information regarding BMS clinical trial participation, please visit www.BMSStudyConnect.com Inclusion Criteria: * Male or female, age 18 or older * Must have had a very recent stroke or transient ischemic attack ("mini stroke") that can be confirmed by the study doctor * Able to be assigned to a study group no later than 48 hours after the stroke occurred * Has an image of the brain that confirms that the stroke was not caused by hemorrhage or other reason that could explain symptoms Exclusion Criteria: * A suspicion by the study doctor that the transient ischemic attack or stroke was caused by a blood clot that formed in the heart; examples of this include history of an abnormal heart rhythm known as atrial fibrillation or a ventricular aneurysm or defect of the heart. * Any condition requiring treatment with an anticoagulant * History of intracranial hemorrhage ("bleeding in the brain") * Gastrointestinal ("stomach or intestinal") bleeding in the last 3 months that required treatment * Planned or anticipated invasive surgery or procedure during the study * Unable to tolerate MRI procedures.