OBJECTIVE: The existing cyclosporine (CsA) population pharmacokinetic (PPK) model does not apply well to children. The aim of the study was to establish a CsA PPK model for Chinese children with nephrotic syndrome (NS) and conduct a dosage simulation to provide drug-dosing guidance. MATERIALS AND METHODS: A total of 311 drug monitoring data points were collected from 165 children. Blood samples were collected before dosing. Non-linear mixed-effects model was applied to develop the PPK model. Covariate analysis was applied to select candidate factors associated with pharmacokinetic (PK) parameters. A model-based simulation was then performed to estimate the optimal initial dose for different patient subgroups. RESULTS: A one-compartment model with first-order absorption and elimination was chosen to describe the drug trajectory in vivo. The typical values for apparent clearance/absorption fraction (CL/F) and apparent volume of distribution/absorption fraction (V/F) were 40.1/h and 2.32 ×103L, respectively. The covariate analysis revealed that weight and total cholesterol were strongly associated with CL/F and V/F. Goodness-of-fit and model evaluation suggested that the proposed model was acceptable. A dosage regimen table was created for specific pediatric groups to facilitate clinical application. CONCLUSION: A PPK model of CsA in Chinese pediatrics was successfully established, allowing the development of individualized dosing regimens for Chinese pediatric NS patients.
OBJECTIVE: The existing cyclosporine (CsA) population pharmacokinetic (PPK) model does not apply well to children. The aim of the study was to establish a CsA PPK model for Chinese children with nephrotic syndrome (NS) and conduct a dosage simulation to provide drug-dosing guidance. MATERIALS AND METHODS: A total of 311 drug monitoring data points were collected from 165 children. Blood samples were collected before dosing. Non-linear mixed-effects model was applied to develop the PPK model. Covariate analysis was applied to select candidate factors associated with pharmacokinetic (PK) parameters. A model-based simulation was then performed to estimate the optimal initial dose for different patient subgroups. RESULTS: A one-compartment model with first-order absorption and elimination was chosen to describe the drug trajectory in vivo. The typical values for apparent clearance/absorption fraction (CL/F) and apparent volume of distribution/absorption fraction (V/F) were 40.1/h and 2.32 ×103L, respectively. The covariate analysis revealed that weight and total cholesterol were strongly associated with CL/F and V/F. Goodness-of-fit and model evaluation suggested that the proposed model was acceptable. A dosage regimen table was created for specific pediatric groups to facilitate clinical application. CONCLUSION: A PPK model of CsA in Chinese pediatrics was successfully established, allowing the development of individualized dosing regimens for Chinese pediatric NS patients.