Comparison of Co-administration of Ezetimibe Plus Simvastatin Versus Simvastatin Alone in Primary Hypercholesterolemia (P03476)

Inclusion Criteria: * Subjects must demonstrate their willingness to participate in the study and comply with its procedures by signing a written informed consent. * Subjects must be \>= 18 years and \<= 75 years of age. * Subjects must have an LDL-C concentration \>= 2.6 mmol/L (100 mg/dL) to \<= 4.1 mmol/L (160 mg/dL) using the Friedewald calculation available at the time of randomization Visit 3 (Baseline Visit). * Subjects must have triglyceride concentrations of \< 3.99 mmol/L (350 mg/dL) at Visit 3 (Baseline Visit). * Subjects must have documented coronary heart disease (CHD). For the purposes of this study, CHD will include one or more of the following features: documented stable angina (with evidence of ischemia on exercise testing); history of myocardial infarction; history of percutaneous coronary intervention (primarily PTCA with or without stent placement); symptomatic peripheral vascular disease (claudication); documented history of atherothrombotic cerebrovascular disease; and/or documented history of unstable angina or non-Q wave myocardial infarction. * Subject must be currently taking simvastatin 20 mg daily and by history has taken 80% of daily evening doses for the preceding 6 weeks prior to Visit 3 (Baseline Visit). * Subjects must have liver transaminases (ALT, AST) \< 50% above the upper limit of normal, with no active liver disease, and CK \< 50% above the upper limit of normal at Visit 3 (Baseline Visit). * Clinical laboratory tests (CBC, blood chemis…