Inclusion Criteria:  Male or female non-smoking subjects between the ages of 50 to 75 years inclusive, without known medical conditions requiring treatment Consumes on average no more than 2 alcoholic drinks per day for 30 days prior to study  Exclusion Criteria:  Abnormal baseline laboratory results Current prescribed use of aspirin, warfarin or other anticoagulants Use of other specific medications within 2 weeks of study start History of certain medical conditions Subject's platelets are unresponsive to arachidonic acid, as defined as <60% of aggregation as measured by light transmittance aggregometry