BACKGROUND: Lowering low-density lipoprotein cholesterol (LDL-C) levels reduces the risk of coronary heart disease. The introduction of a highly efficacious new statin, rosuvastatin, may enable more patients to be treated to LDL-C goal within a fixed budget. OBJECTIVES: To compare the cost-effectiveness of rosuvastatin 10 mg and atorvastatin 10 mg in lowering LDL-C and achieving guideline goals after 12 weeks of treatment. The LDL-C goals were those recommended by the National Cholesterol Education Program Adult Treatment Panel (NCEP ATP) III and the Third Joint European Task Force. METHODS: The analysis was performed on pooled data from three clinical trials. Efficacy was measured as the percent reduction in LDL-C and the proportion of patients who reached guideline LDL-C goals following the first 12 weeks of treatment, prior to dose titration. Costs comprised drug acquisition costs only. The cost-effectiveness measures were cost per 1% reduction in LDL-C and cost per patient treated to their LDL-C goal. RESULTS: Treatment with rosuvastatin 10 mg costs 1.85 per 1% reduction in LDL-C, compared with 2.37 per 1% reduction with atorvastatin 10 mg. The average costs per patient treated to the European LDL-C goals were 130.18 for rosuvastatin 10 mg and 242.44 for atorvastatin 10 mg. Treating to NCEP ATP III goals costs 115 per patient treated with rosuvastatin 10 mg vs. 163 per patient treated with atorvastatin 10 mg. CONCLUSIONS: Rosuvastatin has the same acquisition costs as and is more efficacious than atorvastatin in lowering LDL-C and treating patients to target LDL-C levels.