Comparison of Mw\Pharm 3.30 and Mw\Pharm ++ (Windows version) software for PK/PD monitoring of vancomycin: A priori modeling.

Objective: To evaluate the possibility of population-based dose optimization with the aid of MwPharm modeling and to find the best model in the Windows version (WIN).

Materials: 25 patients repeatedly examined for vancomycin (mean age 63 ± 14 years, body weight 88 ± 21 kg, median dose 1 g/12 h).

Methods: Trough concentrations predicted by WIN models , , , and DOS model (DOS) were compared with the measured value.

Statistics: The percentage prediction error (%PE) calculated as (predicted - measured)/measured values, Blandt-Altman plot, root mean square error (RMSE), Pearson's coefficient of rank correlation (R). Data is presented as mean ± SD. Student's t-test was used for prediction precision evaluation.

Results: The %PE varied from +44.4 ± 65.2% to +76.5 ± 84.3%, p < 0.001. model produced the lowest %PE among WIN models as well as the lowest RMSE (79) and Blandt-Altman bias (-4.01 ± 7.59), but the Pearson's correlation (0.6843, p = 0.0002) was less tight. DOS model produced the second lowest RMSE (81), %PE (+45.9 ± 66.6%), and Blandt-Altman bias (-4.83 ± 6.97) and highest Pearson's R (0.7847, p < 0.0001). produced the third best prediction: RMSE (113), %PE (62.8 ± 92.6%), Blandt-Altman bias (-6.78 ± 11.2) but Pearson's R was the poorest (0.5773, p = 0.0025).

Conclusion: The lowest %PE and highest Pearson's R were achieved by the model. Due to the poor predictive performance of all MwPharm versions and models, we find all of them unsuitable for a priori vancomycin dosing management. Other software should be evaluated for routine use.