A Multicenter, Randomized, Double-Blind, Placebo-Controlled Phase III Clinical Study to Evaluate the Safety and Efficacy of Recombinant Fully Human Anti-PCSK9 Monoclonal Antibody Injection (SAL003) in Combination with Statin Therapy in Patients with Hypercholesterolemia and Mixed Dyslipidemia.

This is a Phase III, multicenter, randomized, double-blind, placebo-controlled study designed to evaluate the efficacy and safety of SAL003, a recombinant fully human anti-PCSK9 monoclonal antibody, in Chinese patients with hypercholesterolemia and mixed dyslipidemia at very high or high cardiovascular risk who have not achieved target LDL-C levels despite stable, moderate- to high-intensity statin therapy (with or without ezetimibe).

Approximately 720 participants will be randomized in a 2:1 ratio to receive either SAL003 140 mg or matching placebo, administered subcutaneously every 4 weeks for 24 weeks. Following the double-blind period, all participants will enter an open-label extension period and receive SAL003 140 mg Q4W for an additional 28 weeks, with a total study duration of 52 weeks.

The primary efficacy endpoint is the percent change from baseline in Low-Density Lipoprotein Cholesterol (LDL-C) at Week 24. Key secondary endpoints include the absolute change in LDL-C, the proportion of subjects achieving LDL-C target levels, and changes in other lipid parameters.

Inclusion Criteria:

• Subjects aged 18 to 75 years.
• On a stable, moderate- to high-intensity statin regimen (with or without ezetimibe) for at least 4 weeks prior to screening.
• Fasting LDL-C above target levels per 2023 Chinese guidelines:

With ASCVD history: ≥1.4 mmol/L (Extreme Risk) or ≥1.8 mmol/L (Very High Risk). Without ASCVD history: ≥2.6 mmol/L (Moderate/High Risk) or ≥3.4 mmol/L (Low Risk).

Fasting triglycerides (TG) ≤ 5.6 mmol/L at screening/randomization.

• Provide signed informed consent.

Exclusion Criteria:

• Homozygous Familial Hypercholesterolemia (HoFH).
• Uncontrolled hypertension (SBP ≥160 mmHg or DBP ≥100 mmHg).
• Significant cardiovascular event (e.g., MI, unstable angina, stroke, PCI, CABG) within 3 months prior to screening.
• Heart failure (NYHA Class III or IV) or LVEF <40% within 3 months.
• Severe renal impairment (eGFR <30 mL/min/1.73m²).
• Active liver disease or significant hepatic impairment (ALT/AST >2.5x ULN or TBiL >2x ULN).
• Uncontrolled diabetes (HbA1c >8.0%) or type 1 diabetes.
• Use of other lipid-lowering therapies (e.g., fibrates, niacin) within 3 months or any PCSK9 inhibitor within 6 months prior to screening.
• Known hypersensitivity to any component of the investigational product or other antibody therapies.