OBJECTIVES: Assess cost-effectiveness of switching patients to ezetimibe 10mg (EZ10) co-administration with simvastatin 20mg (S20) versus an atorvastatin titration strategy (patients are titrated to goal or maximum atorvastatin dose of 80mg) in CHD and CHD equivalent patients not at goal with atorvastatin 10mg (A10) monotherapy. METHODS: Decision-analytic model developed to project lifetime costs and benefits of lipid therapy. Clinical trial data were used to estimate LDL-C reductions for different treatment strategies. Effect of LDL-C reductions on CHD event rates was estimated using Framingham equations and Spanish Instituto Nacional de Estadística data on nonCHD-related mortality. Direct costs of CHD events in Spain, Spanish prices for simvastatin, atorvastatin and EZ10 were used to project lifetime costs. Model was run for a population consisting of all CHD and CHD-equivalent patients started on A10 in an observational Lipid Lowering Treatment study conducted in Spain, and not at LDL-C goal after 60 days of treatment. RESULTS: For these patients N=54 (mean age 62.5 years, 64.8% male, lipid profile on A10 mean LDL-C 148.7 mg/dl, TC 225.9 mg/dl, HDL 45.9 mg/dl), switching to EZ10 co-administered with S20 compared to atorvastatin titration is projected to increase the life expectancy from 15.99 to 16.31 years for CHD patients and from 18.11 to 18.23 years for CHD equivalent patients with a discounted incremental cost per life year gained of 7,855 EURO for CHD patients and 15,356 for CHD equivalent patients. CONCLUSION: Switching to EZ10 co-administered with simvastatin for CHD and CHD equivalent patients not at goal on atorvastatin is projected to be a cost-effective alternative to atorvastatin titration.