This multicenter, randomized, parallel groups, placebo-study is designed for subjects with primary hypercholesterolemia [plasma LDL-C concentrations between >= 2.6 mmol/L (100 mg/dL) to <= 4.1 mmol/L (160 mg/dL) and triglyceride concentrations of < 3.99 mmol/L (350 mg/dL) and coronary heart disease who are currently being treated with atorvastatin 10 mg and would benefit from additional reduction in LDL-C.~This study will assess whether the daily co-administration of ezetimibe 10 mg to ongoing treatment with atorvastatin 10 mg will be more effective than treatment with atorvastatin 10 mg alone in further reducing LDL-C concentrations and in achieving LDL-C target goal as defined by the ESC or National Cholesterol Education Program (NCEP) guidelines at the time of database lock.~The primary objective is to compare the efficacy of ezetimibe 10 mg added daily to ongoing treatment with atorvastatin 10 mg versus ezetimibe placebo added daily to ongoing treatment with atorvastatin 10 mg in reducing the concentration of LDL-C at endpoint after 6 weeks of treatment.~The secondary objective is to compare the efficacy of ezetimibe 10 mg added to ongoing treatment with atorvastatin 10 mg daily versus ezetimibe placebo added to ongoing treatment with atorvastatin 10 mg daily after 6 weeks of treatment with respect to:~The percentage of subjects who achieve the target LDL-C goal as defined by the ESC or NCEP guidelines at the time of database lock.~Change in the concentrations of total cholesterol, HDL-C and triglycerides.~Safety and tolerability. Approximately 200 subjects will be enrolled into the study to insure that at least 160 subjects complete the study. Each site will enroll approximately 20 subjects for a total of approximately 200 subjects.~The duration of the study for each subject will be approximately 7 weeks. Each subject will be scheduled for 3-4 study visits. Visits 1 and 2 are screening visits; these visits may be combined. At Visit 3, those subjects who meet the enrollment criteria will be randomized to one of two treatment groups: ezetimibe 10 mg or ezetimibe placebo to be taken with ongoing open-label atorvastatin 10 mg/day. Randomization will be stratified based on the LDL-C level at Visit 3: < 3.3 mmol/L (130 mg/dL) or >= 3.3 mmol/L (130 mg/dL). Subjects will be treated for 6 weeks and then return for a final visit, Visit 4.
This is a multicenter, randomized, parallel group, placebo controlled study designed to evaluate the efficacy, safety, and tolerability of ezetimibe added to ongoing atorvastatin therapy compared with ongoing atorvastatin treatment alone. This study will involve subjects with primary hypercholesterolemia and coronary heart disease (CHD) who are currently being treated with atorvastatin and who would benefit from additional reduction in low-density lipoprotein cholesterol (LDL-C).