Comparison of Trough-Only and Peak–Trough Concentration Data for the Calculation of Vancomycin Area under the Concentration–Time Curve on Day 2 Using Previous and Updated Population Pharmacokinetic Models

Area under the concentration–time curve (AUC)-guided dosing for vancomycin requires the measurement of both peak and trough concentrations. Recently, a novel population pharmacokinetic model (Bayesian-based, free-web application PAT version 4.0) was developed. The aim of the present study was to verify whether this optimized pharmacokinetic model improved the predictive accuracy of AUC calculated using trough-only data compared to data obtained using trough and peak sampling on Day 2. We conducted a single-center, cohort study to evaluate the agreement of AUC calculated using trough-only data compared to peak–trough sampling on Day 2, and to compare results obtained with the Yasuhara (previous) and Oda (updated) pharmacokinetic models. The proportion of trough/peak–trough AUC24–48 ratios within a 5% difference was significantly higher with the Oda model than with the Yasuhara model (75 vs. 58.3%, p = 0.034). Furthermore, multivariate logistic regression analysis showed that implementation of the Oda model was a significant factor associated with deviation of trough/peak–trough AUC24–48 within 5% (odds ratio 2.36, 95% confidence interval, 1.05–5.05, p = 0.027). The updated model offers enhanced predictive performance for AUC24–48 estimation using trough-only data. Further development of strategies to improve the predictive accuracy of AUC24–48 using trough-only data is warranted.