The use of acetylsalicylic acid in the primary prevention of cardiovascular events has been extensively studied. However, the overall risk level of the study populations was low (< 10% 10-year CHD risk). The current study is designed to prove the efficacy and tolerability of 100 mg enteric-coated Aspirin versus placebo in the prevention of cardiovascular disease (CVD) events, which include fatal and nonfatal myocardial infarction, fatal and nonfatal stroke and CV death, in a population with no history of known CVD who are at moderate risk of major CHD events (approximately 10-20% 10 year CHD risk). This corresponds to a patient population mean 10-year CVD risk of approximately 30%. Subjects are treated in a standard care setting and may receive treatment for the underlying risk factors as defined by the treating physician. Outcome events will be adjudicated by an Endpoint Adjudication Committee and the study will be monitored by an independent Data Safety Monitoring Board.