Cost comparison of linezolid versus vancomycin for treatment of complicated skin and skin-structure infection caused by methicillin-resistant Staphylococcus aureus in Quebec.

Background: In Canada, complicated skin and skin-structure infection (cSSSI) caused by methicillin-resistant Staphylococcus aureus (MRSA) is usually treated with antibiotics in hospital, with a follow-up course at home for stable patients. The cost implications of using intravenous and oral linezolid instead of intravenous vancomycin in Canadian clinical practice have not been examined.

Objectives: To evaluate the potential treatment cost impact for the Quebec health care system of linezolid versus vancomycin for MRSA-related cSSSI therapy, using a net impact analysis approach.

Methods: Health care resource use associated with linezolid and vancomycin therapy was estimated for patients in Quebec, based on expert opinion. Costs were assigned to health care resources (antibiotics, medical supplies, laboratory testing and health care professional time) based on unit prices. The base-case analysis assumed 14 days of antibiotic treatment for both agents; five days in hospital followed by nine days at home. Therapy duration, length of inpatient treatment and discharge rates were varied in sensitivity analyses.

Results: Antibiotic costs were higher for linezolid than for vancomycin, for both inpatient ($874 versus $144, respectively) and outpatient therapy ($1,356 versus $1,242, respectively). Compared with vancomycin, lower costs for antibiotic preparation, administration and monitoring of linezolid offset drug acquisition costs. Total treatment costs were $3,850 for linezolid versus $5,189 for vancomycin. Results were sensitive to the number of treatment days spent at home and the discharge rate.

Conclusion: Using linezolid instead of vancomycin to treat MRSA-related cSSSI, for hospital and home courses combined, may reduce health care resource utilization and costs in Quebec.