This study is a multicenter, randomized, open-label, parallel, phase IV trial.

The purpose of this study efficacy and safety of combination therapy of moderate-intensity statin and ezetimibe compared to high-intensity statin.

The study is planned to include 272 patients with a clinical atherosclerotic cardiovascular disease requiring optimal statin therapy.

After enrollment, subjects are randomized into two groups in a 1:1 manner. The combination therapy group will receive a single-pill combination of rosuvastatin 10 mg and ezetimibe 10 mg once daily.

The subjects in the intensive statin group will receive rosuvastatin 20 mg once daily.

Subjects will visit at weeks 12 and 24 to identify medication adherence and clinical side effects.

The primary endpoint of this study is a % change of low-density lipoprotein cholesterol at 12 weeks.

Inclusion Criteria:

1. Aged between 19 and 75 years

2. Presence of atherosclerotic cardiovascular disease Coronary artery disease

   • History of acute coronary syndrome
   • Stable or unstable angina
   • History of coronary revascularization Stroke or TIA Peripheral arterial disease, history of peripheral arterial revascularization

3. Patients who have been taking lipid-lowering agents (statin or ezetimibe) for ≥4 weeks at the time of randomization

4. Patients who gave informed consent

Exclusion Criteria:

1. Patients who have used lipid-lowering agents other than statin or ezetimibe within the last 3 months
2. A serum triglyceride on fasting >400 mg/dL
3. A history of muscular symptoms or rhabdomyolysis due to the use of statin
4. Hypersensitivity to rosuvastatin or ezetimibe
5. Labeled contraindications to rosuvastatin or rosuvastatin Severe renal impairment (CrCl <30 mL/min by Cockcroft-Gault formula or estimated GFR <30 mL/min / 1.73 m2 by MDRD equation) ALT, AST ≥3 × ULN or active liver disease CPK ≥3 × ULN
6. Enrollment of other clinical trials within 30 days
7. Any other issues that the treating physician assumes ineligible for participation in the trial