Table 2. Population primary parameters of Fosfomycin in horses with a 3-compartment model (Legend: between-subject variability (BSV)%, CV%, and 2.5% and 97.5% percentiles give the precision of typical value estimates).
| Primary structural Parameters | Units | BSV% | Typical values (Median) | CV% | 2.50% | 97.50% |
|---|---|---|---|---|---|---|
| tvV | L/kg | 17.2 | 0.08 | 9 | 0.066 | 0.094 |
| tvV2 | L/kg | 10.2 | 0.055 | 9.8 | 0.044 | 0.066 |
| tvV3 | L/kg | 23.1 | 0.059 | 13.2 | 0.044 | 0.074 |
| tvCL | L/kg/hr | 15.9 | 0.07 | 7.4 | 0.06 | 0.08 |
| tvCL2 | L/kg/hr | 55.8 | 0.017 | 28.1 | 0.008 | 0.027 |
| tvCL3 | L/kg/hr | 49.7 | 0.22 | 29.6 | 0.09 | 0.35 |
| tvCMultStdev (residual, proportional) | Scalar | 0.048 | 18.5 | 0.03 | 0.066 | |
| stdev0 (residual, additive) | µg/L | 0.249 | 19.5 | 0.153 | 0.346 | |
| Secondary parameters | ||||||
| Half_life_alpha | hr | 0.099 | 26.3 | 0.047 | 0.151 | |
| Half_life_Beta | hr | 1.029 | 17.2 | 0.677 | 1.381 | |
| Half_life_Gamma | hr | 3.191 | 20.2 | 1.91 | 4.472 | |
| Vss (steady-state volume of distribution) | L/kg | 0.194 | 4.8 | 0.176 | 0.213 | |
| MRT (Mean residence time (IV)) | hr | 2.768 | 8.3 | 2.313 | 3.223 | |
| AUC | µg*hr/mL | 288.7 | 5.8 | 247.8 | 311.8 | |
| AUMC | µg*hr2/mL | 798.9 | 11.4 | 626 | 980.3 | |
The primary estimated parameters were the volume of distribution of the central compartment (V1), the volume of distribution of the peripheral compartments (V2, V3), the plasma clearance (CL) and the distribution clearances (CL2, CL3). CMultStdev corresponds to the proportional component of the residual error and stdev0 is the additive component of the residual. The estimated fixed parameters were reported as their typical values (tv) with their CV% and their confidence interval that is a measure of the precision of their estimation. Secondary parameters are the half-life of the different phases, the steady-state volume of distribution (Vss), the mean residence time (MRT), area under the curve (AUC) and area under the moment curve (AUMC).