OBJECTIVES: Methicillin-resistant Stapylococcus aureus (MRSA) pneumonia is a life-threatening disease worldwide. In Japan, vancomycin (VCM), teicoplanin (TEIC), and linezolid (LZD) are drugs of choice for MRSA pneumonia treatment, but the pharmacoeconomic evaluation of these medications are still unknown. Our study aimed to evaluate clinical and economic outcomes of patients with different pharmacotherapy from the healthcare payer’s perspective.

METHODS: A retrospective study was performed using cost-minimization analysis (CMA). Costs included medical costs such as therapeutic drug monitoring fee, bacterial microscopy, chest radiography, and general ward hospitalization (nurse -patient ratio, 7:1 per day). Authorized medication costs were recorded for original brands and generic brands of each MRSA medication. Length of stay using VCM, TEIC, and LZD to treat MRSA pneumonia was taken to be 12 days, 12 days, and 10 days from articles, respectively. Sensitivity analysis was used to compare the costs of original VCM with those of other MRSA medications for original medication prices as well as generic medication prices. Second sensitivity analysis was performed to compare the costs of MRSA medications in terms of severity of MRSA infections.

RESULTS: Total costs of VCM, TEIC, and LZD were 320,748 yen, 352,200 yen, and 461,240 yen, respectively. The results from both CMA based model analysis and sensitivity analyses showed VCM is the most cost-minimized medication for MRSA pneumonia in Japan.

CONCLUSIONS: To our knowledge, this is the first clinical pharmacoeconomic evaluation of treatment of MRSA pneumonia in Japan. Our study results will provide potential economic evidence in supporting the formulary decisions in the hospital.