A Population-Based Pharmacokinetic Model Approach to Pantoprazole Dosing for Obese Children and Adolescents
08/2018
Journal Article
Authors:
Shakhnovich, V.;
Brian Smith, P.;
Guptill, J. T.;
James, L. P.;
Collier, D. N.;
Wu, H.;
Livingston, C. E.;
Zhao, J.;
Kearns, G. L.;
Cohen-Wolkowiez, M.
Volume:
20
Pagination:
483-495
Issue:
5
Journal:
Paediatr Drugs
PMID:
30097906
URL:
https://www.ncbi.nlm.nih.gov/pubmed/30097906
Keywords:
2-Pyridinylmethylsulfinylbenzimidazoles/administration & dosage/*pharmacokinetics Administration, Oral Adolescent Area Under Curve Body Weight Child Female Humans Male Metabolic Clearance Rate *Models, Biological Obesity/*complications Pantoprazole
Prospective Studies Proton Pump Inhibitors/administration & dosage/*pharmacokinetics
Abstract:
BACKGROUND AND AIMS: Pharmacokinetic data for proton pump inhibitors (PPIs), acid-suppression drugs commonly prescribed to children, are lacking for obese children who are at greatest risk for acid-related disease. In a recent multi-center investigation, we demonstrated decreased, total body weight adjusted, apparent clearance (CL/F) of the PPI pantoprazole for obese children compared with their non-obese peers. Subsequently, we developed a population-based pharmacokinetic (PopPK) model to characterize pantoprazole disposition and evaluated appropriate pantoprazole dosing strategies for obese pediatric patients, using simulation. METHODS: Pharmacokinetic data from the only prospective study of PPIs in obese children (aged 6-17 years; n = 40) included 273 pantoprazole and 256 pantoprazole-sulfone plasma concentrations, after single oral-dose administration, and were used for pantoprazole model development and covariate analysis (NONMEM((R))). Model evaluation was performed via bootstrapping and predictive checks, and the final model was applied to simulate systemic pantoprazole exposures for common dosing scenarios. RESULTS: A two-compartment PopPK model, which included CYP2C19 genotype and total body weight, provided the best fit. Resultant, typical, weight-normalized pantoprazole parameter estimates were different than previously reported for children or adults, with significantly reduced pantoprazole CL/F for obese children. Of the dosing scenarios evaluated, the weight-tiered approach, approved by the US Food and Drug Administration, achieved pantoprazole exposures [area under the curve (AUC(0-infinity))] within ranges previously reported as therapeutic, without over- or under-prediction for obese children. CONCLUSIONS: Our data argue against empiric dose escalation of PPIs for obese children and support current FDA-approved pediatric weight-tiered dosing for pantoprazole; however, 3- to 5-fold inter-individual variability in pantoprazole AUC(0-infinity) remained using this dosing approach.
