[2026-09-22] Efficacy and Safety of PCSK9 Inhibitors in Patients With Atherosclerotic Cardiovascular Disease at a Tertiary Hospital in the Northeast of Thailand

Background: Elevated low-density lipoprotein cholesterol (LDL-C) remains inadequately controlled in Thai patients with atherosclerotic cardiovascular disease (ASCVD) despite intensive statin-ezetimibe therapy. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors offer substantial LDL-C reduction, but real-world data from Thailand remain limited. Objective: To evaluate the longitudinal effectiveness and safety of alirocumab and evolocumab in Thai patients with ASCVD. Methods: This retrospective cohort study included 137 ASCVD patients initiating PCSK9 inhibitor therapy at Queen Sirikit Heart Center of the Northeast, Thailand (January 2021 to May 2024), with 12-month follow-up. Patients were grouped by treatment group (continued or switched), and LDL-C at baseline and months 3, 6, 9, and 12 was compared using a linear mixed-effects model. Target attainment (< 70 and < 55 mg/dL) was analyzed using generalized estimating equations. Results: Mean (SD) age was 63.2 (9.9) years (66.4% male), and a total of 79.6% had chronic coronary syndrome. Mean baseline LDL-C was 155.4 mg/dL, decreasing to 56.3 mg/dL at month 3 and remaining stable through month 12 (55.2 mg/dL). LDL-C targets of < 70 and < 55 mg/dL were achieved in 65%-78% and 54%-69% of patients, respectively. Cardiovascular events occurred in 2 patients (1.4%), with no myocardial infarction or stroke. Adverse events occurred in 6.5% of patients, with no serious drug-related discontinuations. Switching between agents did not compromise lipid-lowering efficacy. Conclusion: PCSK9 inhibitors were associated with sustained LDL-C reduction and infrequent adverse events among Thai ASCVD patients in real-world practice, supporting their effectiveness and the importance of treatment continuity and access.