IBI306 is a fully human monoclonal antibody that binds proprotein convertase substilisin/kexin type 9 (PCSK-9), preventing its interaction with the low-density lipoprotein cholesterol receptor (LDL-R) and thereby restoring LDL-R recycling and low-density lipoprotein cholesterol(LDL-C) uptake. This study is being done to investigate the effects of IBI306 in Chinese people with non-familial hypercholesterolemia with very high or high cardiovascular risk. This study will see if IBI306 will reduce low density lipoprotein cholesterol (LDL-C) in Chinese people who are taking a certain type of lipid-lowering medication (statins with or without ezetimibe) and whether it causes any side effects

This is a phase 3, multicenter, double-blind, randomized, placebo-controlled study of IBI306 in Chinese non-familial hypercholesterolemia Subjects with very high or high cardiovascular risk. A total of around 600 subjects who meet admission criteria will be randomized and receive one of the two dose levels of IBI306 or matching placebo: 450mg Q4W, or 600mg Q6W. The double blind period for both groups will be 48 weeks. The study will last 52 weeks

Inclusion criteria:

1. Males and females ≥ 18 to ≤ 75 years of age
2. Diagnosis of hypercholesterolemia
3. LDL cholesterol ≥ 70 mg/dl (1.8mmol/L)
4. Very high or high cardiovascular risk
5. TG≤500 mg/dL(5.64 mmol/L)

Exclusion criteria:

1. Diagnosis of HoFH or HeFH
2. Uncontrolled hypertension
3. Uncontrolled hyperthyroidism or hypothyroidism
4. Severe renal dysfunction
5. Known sensitivity to any of the products to be administered during dosing