Cost-utility analysis of add-on ezetimibe to moderate-intensity statin versus moderate-intensity statin alone for secondary prevention in patients with acute coronary syndrome intolerant to high-intensity statin therapy in Thailand

Background Although high-intensity statin therapy is recommended for the secondary prevention of acute coronary syndrome (ACS), a subset of patients is unable to tolerate such regimens due to statin-associated adverse effects. For these patients, adding ezetimibe to a maximally tolerated moderate-intensity statin is a guideline-recommended lipid-lowering strategy. This study aimed to evaluate the cost-utility of ezetimibe added to moderate-intensity statin therapy, compared with moderate-intensity statin therapy alone, for the secondary prevention of ACS in Thailand. Methods A Markov model with four health states was developed. Incremental cost-effectiveness ratios (ICERs) were estimated to compare strategies from both societal and healthcare provider perspectives. Transition probabilities, utility values, and cost inputs were derived from the IMPROVE-IT trial and relevant literature, supplemented with Thailand-specific data. Costs (2024 Thai baht [THB]) and outcomes were discounted at an annual rate of 3%. One-way and probabilistic sensitivity analyses were conducted. The intervention was considered cost-effective if the ICER was below the Thai willingness-to-pay (WTP) threshold of 160,000 THB per QALY (4,533 USD/QALY). Results Ezetimibe added to moderate-intensity statin therapy yielded an ICER of 155,312 THB/QALY (4,400.4 USD/QALY) from the societal perspective and 148,934 THB/QALY (4,219.7 USD/QALY) from the healthcare provider perspective; both were below the 160,000 THB/QALY threshold. In the one-way sensitivity analysis, the relative risk of death from myocardial infarction (MI) associated with ezetimibe was the most influential parameter (ICER change: −27.31% to +54.32%). Probabilistic sensitivity analysis indicated a 56.8% probability of cost-effectiveness at the predefined threshold. Conclusion These findings suggest that adding ezetimibe to moderate-intensity statin therapy may be cost-effective compared with moderate-intensity statin monotherapy for the secondary prevention of ACS among patients in Thailand who are intolerant to high-intensity statins. However, because the base-case ICER was only marginally below the national threshold and probabilistic sensitivity analysis showed a 56.8% probability of cost-effectiveness, the results should be interpreted with appropriate caution.