Real-world evidence on prescribing patterns and lipid-lowering effectiveness of monoclonal antibody PCSK9 inhibitors from Hong Kong

Despite the approval of monoclonal antibody proprotein convertase subtilisin–kexin type 9 inhibitors (PCSK9i) across Asia, real-world evidence investigating their utilization and lipid-lowering effectiveness in large cohorts remains scarce.1,2 In Hong Kong, alirocumab and evolocumab (hereafter PCSK9i) were approved in 2016 with label indications matching those in the USA and Europe, namely, hypercholesterolaemia and mixed dyslipidaemia, heterozygous familial hypercholesterolaemia (FH), homozygous FH, and established atherosclerotic cardiovascular disease (ASCVD). Beginning in January 2021, PCSK9i were reimbursed when prescribed by a cardiologist or endocrinologist to patients with (i) heterozygous FH [with ASCVD or with low-density lipoprotein cholesterol (LDL-C) ≥ 3.4 mmol/L receiving maximally tolerated statin plus ezetimibe], (ii) acute coronary syndrome with LDL-C ≥ 1.8 mmol/L, or (iii) homozygous FH (evolocumab only). These patients can receive PCSK9i with a minimal co-payment of approximately USD 2 per prescription. We used Hong Kong Hospital Authority electronic health records to identify all patients initiating a PCSK9i, regardless of indication, between 1 August 2016 and 31 December 2024, with follow-up through 31 July 2025. This territory-wide database covers all 7.5 million residents of Hong Kong and captures all public-sector PCSK9i prescriptions (approximately 70% of the PCSK9i market share in 2024) in outpatient and inpatient settings. The first PCSK9i prescription date was the index date, and we excluded patients missing age or sex (n = 84) and those