Cost-effectiveness analysis of serum vancomycin concentration monitoring in patients with hematologic malignancies.

OBJECTIVE This study evaluates the cost-effectiveness of vancomycin serum concentration monitoring in patients with hematologic malignancies. METHODS The study was designed as a prospective randomized study. Seventy immunocompromised febrile patients with hematologic malignancies were randomly assigned to either a vancomycin therapeutic drug monitoring group (TDM group; n = 37) or to a control group (n = 33). Intervention in the TDM group involved patient follow-up by a clinical pharmacist to obtain and pharmacokinetically interpret serum vancomycin concentrations for dosage individualization. RESULTS Evaluation of all patients included global clinical response and nephrotoxicity, as well as the economic costs and effectiveness derived from the vancomycin monitoring program. There were no significant differences between the TDM and control groups in the outcome measures, except for the incidence of nephrotoxicity: the rates of minor nephrotoxicity were 33.3% and 13.5% in the control and TDM groups, respectively. The corresponding figures for moderate nephrotoxicity were 9.1% and 0%. Logistic regression analysis confirmed that TDM independently reduced the incidence of nephrotoxicity in this patient population. On the basis of this reduced nephrotoxicity, a incremental cost of $435 per case of nephrotoxicity prevented was found for vancomycin serum concentration monitoring. CONCLUSIONS A decreased incidence of nephrotoxicity provides evidence of a real clinical benefit to patient management in patients with hematologic malignancies. The TDM for vancomycin therapy in this high-risk population has been shown to be a cost-effective procedure.