Inclusion Criteria:  (I) 18 - 80 years of age, (II) diagnosed as stable coronary artery disease or acute coronary syndrome during admission (III) undergoing clinically indicated coronary angiography and identified with at least one intermediate lesion (50%-70% diameter stenosis) on de novo coronary arteries, (IV) have an elevated LDL-C values (LDL-C≥100 mg/dL) despite taken rosuvastatin 10 mg/day or atorvastatin 20 mg/day for 2-4 weeks after initiation or with maximally tolerated statin therapy, (V) able to provide written, informed consent.  Exclusion Criteria:  Patients who have been treated previously with at least one dose of any anti-PCSK9 monoclonal antibody received target vessel revascularization Known hypersensitivity or have contraindications to any anti-PCSK9 monoclonal antibody or statins Unable to receive OCT imaging tests Known history of hemorrhagic stroke Currently under treatment for cancer Baseline triglyceride > 400 mg/dl Patients with severe liver or renal dysfunction Pregnant or breast-feeding women Considered by the investigator as inappropriate for this study for any reason