PCSK 9 Inhibitor Added to High-Intensity Statin Therapy to Prevent Cardiovascular Events in Patients With ACS After PCI

The primary objective was to evaluate the effect of PCSK 9 Inhibitor (initiated within 4 h from PCI for the culprit lesion) with high-intensity statin treatment, compared to placebo with high-intensity statin treatment, on cardiovascular events (including cardiovascular death, myocardial infarction, stroke, re-hospitalization due to acute coronary syndromes or heart failure, or any ischemia-driven coronary revascularization) in patients with acute coronary syndrome and multiple lesions. Alirocumab was used before June 10, 2025; Tafolecimab has been used from June 10, 2025 onward.

Inclusion Criteria: 1. The subject, or their legal guardian, must have a clear understanding of the trial's design and treatment procedures. They must provide written informed consent before any trial-specific tests or procedures are conducted. 2. Both male and female subjects aged ≥18 years. 3. Subjects who have experienced an ACS and have undergone PCI for culprit lesions (either QFR or FFR \< 0.8) are eligible. ACS is defined as: (1) Unstable angina (characterized by rest pain lasting between 5 and 30 minutes or worsening exertional angina accompanied by either transient ST segment depression or elevation, or angiography revealing visually estimated diameter stenosis of 90% or greater, or a ruptured plaque or thrombotic lesion), or (2) Non-ST elevation myocardial infarction, indicated by positive troponin levels consistent with the clinical syndrome and non-ST segment elevation, or (3) ST elevation myocardial infarction, indicated by positive troponin levels consistent with the clinical syndrome and ST-segment elevation. 4\. Low-density lipoprotein cholesterol levels must meet the following criteria: 1. Low-density lipoprotein cholesterol ≥70 mg/dL (≥1.8 mmol/L) in patients who have been on a stable high-intensity statin regimen for at least 4 weeks before enrollment. 2. Low-density lipoprotein cholesterol ≥90 mg/dL (≥2.3 mmol/L) in patients who have been on a moderate or low-intensity statin regimen before enrollment. 3. Low-density lipoprotein cholesterol ≥125 mg/dL (≥3.2 mmol/L) in patients who are statin-naïve or have not been on a stable statin regimen for at least 4 weeks before enrollment. 5\. Subjects must have at least one culprit lesion for ACS in a major native coronary artery (diameter stenosis \>70% with a QFR or FFR\