Economic evaluation of ezetimibe combined with simvastatin for the treatment of primary hypercholesterolaemia.

OBJECTIVE: This study aims to assess the cost-effectiveness of ezetimibe plus simvastatin (E/S) versus atorvastatin or simvastatin monotherapy as second-line treatment of primary hypercholesterolaemia from the Dutch healthcare perspective. METHODS: The evaluation used a Markov model and patient data from the Dutch EASEGO study in which patients failing to reach goal low-density lipoprotein cholesterol levels on atorvastatin 10 mg or simvastatin 20 mg had their dose doubled or switched to ezetimibe 10 mg plus generic simvastatin 20 mg (E10/S20). The second scenario, based on Dutch guidelines, switched patients from simvastatin 40 mg to atorvastatin 40 mg, or ezetimibe 10 mg was added to simvastatin 40 mg (E10/S40). The key effectiveness input measure was change in total cholesterol/high-density lipoprotein ratio obtained from the EASEGO study. In conformity with published studies linking reduced lipid levels to reduced risk of cardiovascular events, the present model assumed that a lipid decrease with ezetimibe may be a signal for reduced risk of cardiovascular events. Model parameters were derived from published literature. Sensitivity analyses were performed for the key parameters. RESULTS: In the EASEGO scenario, incremental cost-effectiveness ratio for E10/S20 was 3497/quality-adjusted life-years (QALY) vs atorvastatin 20 mg and 26,417/QALY vs simvastatin 40 mg. In the Dutch guidelines scenario, E10/S40 was dominant (more effective and cost-saving) vs atorvastatin 40 mg. Varying model inputs had limited impact on the cost-effectiveness of E/S. CONCLUSIONS: The analysis showed the cost-effectiveness of E/S versus atorvastatin 20 mg or simvastatin 40 mg (EASEGO scenario) at a threshold of 30,000/QALY and vs atorvastatin 40 mg was dominant (Dutch guidelines). Thus, E/S seems a valuable cost-effective second-line treatment option for patients not attaining lipid treatment goals.