Linezolid versus vancomycin cost in the treatment of staphylococcal pneumonia

Staphylococcusaureus is involved in around 20% of nosocomial pneumonia cases. Vancomycin used to be the reference antibiotic in this indication, but new molecules have been commercialized, such as linezolid. Previous studies comparing vancomycin and linezolid were based on models. Comparing their real costs from a hospital perspective was needed.

We performed a bicentric retrospective analysis with a cost-minimization analysis. The hospital antibiotic acquisition costs were used, as well as the laboratory test and administration costs from the health insurance cost scale. The cost of each hospital stay was evaluated using the national cost scale per diagnosis related group (DRG), and was then weighted by the stay duration.

Fifty-eight patients were included. All bacteria identified in pulmonary samples were S. aureus. The cost of nursing care per stay with linezolid was €234.10 (SD=91.50) vs. €381.70 (SD=184.70) with vancomycin (P=0.0029). The cost of laboratory tests for linezolid was €172.30 (SD=128.90) per stay vs. €330.70 (SD=198.40) for vancomycin (P=0.0005). The acquisition cost of linezolid per stay was not different from vancomycin based on the price of the generic drug (€54.92 [SD=20.54] vs. €40.30 [SD=22.70]). After weighting by the duration of stay observed, the mean cost per hospital stay was €47,411.50 for linezolid and €57,694.0 for vancomycin (NSD).

These results, in favor of linezolid, support other former pharmacoeconomic study based on models. The mean cost per hospitalization stay was not statistically different between the two study groups, but a trend in favor of linezolid is emerging.