A Multi-center, Randomized, Double-blind, Phase III Clinical Trial to Evaluate the Efficacy and Safety of Combination Therapy of Rosuvastatin and Ezetimibe and Rosuvastatin Monotherapy in Patients with Primary Hypercholesterolemia

Inclusion Criteria:

1. Adults aged 19 years or older
2. Patients with primary hypercholesterolemia
3. Patients who were informed about the purpose, method, effects, risks of this clinical study and have provided a written consent form signed by him/herself or by a representative
4. those who show an LDL-C level of 250 mg/dL or below and a TG level of less than 350 mg/dL at the run-in period (Week -1), and fall under the criterion of requiring the administration of antidyslipidemic drug of NCEP ATP III

Exclusion Criteria:

1. Patients with hypersensitivity to the investigational product or its ingredients
2. Those with an uncontrolled hypertension (SBP ≧ 180 mmHg or DBP ≧ 100 mmHg)
3. Those with a history of unstable angina, myocardial infarction, transient ischemic attack, cerebral vascular disease, coronary artery bypass or coronary intervention within 3 months of screening date
4. Those with a history of malignant tumor within 5 years
5. Those with a history of myopathy or rhabdomyolysis
6. Those who show clinically significant confirmed laboratory test results (1) Patients showing AST or ALT level of greater than 2 times the institutional upper limit of normal or those with active liver disease or chronic hepatitis (2) A serum creatinine level greater than 2 times the institutional upper limit of normal (3) HbA1c > 9% (4) Those with TSH level of greater than 1.5 times the institutional upper limit of normal (5) Those with CK level greater than 2 times the institutional upper limit of normal (However, except for an increase caused by a recent trauma, intramuscular injection or strenuous exercise)
7. Those who were given, within 4 weeks prior to the baseline (8 weeks in case of fibrate) or are expected to be given during the study period, a drug that can have an effect on the efficacy assessment of the clinical study (eg: antidyslipidemic drug (statins, ezetimibe, fibrates, BAS, nicotinic acid and derivative, etc.), systemic glucocorticosteroids, steatolytic enzyme inhibitor, cyclosporine, HIV proteinase inhibitor, macrolide class antibiotics, etc.)
8. Patients who were given estrogen within 3 months from the screening or those who are expected to be given an administration during the study period. (However, a patient who is under a hormone replacement therapy (HRT) will be allowed if no dose change is expected in the course of the clinical study.)
9. Those with a history of alcohol or drug abuse
10. Patients with a hereditary disorder of galactose intolerance, Lapp lactase deficiency or glucose-galactose malabsorption
11. Pregnant or breast-feeding women
12. Women of childbearing potential or men who do not intend to use an adequate contraceptive measure during the study period and for 4 weeks after the end of the study(Adequate contraception: Administration and transplantation of a progestin-only contraceptive pill, intrauterine device, condom, spermicidal agent, etc.)
13. Patients who participated in another clinical study within 3 months from the screening date or have not had a washout period of at least 5 times the half-life of the active ingredient of the previously administered investigational product, whichever is longer
14. Those with drug malabsorption
15. Patients who has been judged by the investigator to be ineligible to participate in the clinical study