Maturation and growth of renal function: Dosing renally cleared drugs in children
Journal Title: The AAPS Journal - Year 2000, Vol 2, Issue 1
Abstract
A model was developed that characterized the maturation and growth of the renal function parameters (RFPs) glomerular filtration rate (GF), active tubular secretion (AS), and renal plasma flow (QR). Published RFP values were obtained from 63 healthy children between the ages of 2 days and 12 years. Maturation over time was assumed to be exponential from an immature (RFPim) to a mature (RFPma) level; for growth, RFPim and RFPma were assumed to follow the allometric equation: RFP(age, W)=aWbe−kmat*age+cWb(1−e−kmat*age), where W is body weight, kmat is the maturation rate constant, b is the body weight exponent, and a and c are RFPim and RFPma at unit W. The model-based equation was fitted to the age-W, RFP values by a nonlinear least-squares method. For GF, the maturation half-life was 7.9 months (90% maturation, 26 months), the body weight exponent was 0.662, and the ratio c/a (which reflected the magnitude of the maturation influence) was 3.1. For AS and QR, the maturation half-lives were about 3.8 months and the ratio c/a was about 1.8. For renally eliminated drugs, the model can be used to estimate dosing regimens that are based on the adult dosing regimen and the age and weight of the child.
Authors and Affiliations
William L. Hayton
Issues and Challenges of Subvisible and Submicron Particulate Analysis in Protein Solutions
The online version of this article (doi:10.1208/s12248-012-9335-8) contains supplementary material, which is available to authorized users.
Model-Based Decision Making in Early Clinical Development: Minimizing the Impact of a Blood Pressure Adverse Event
We describe how modeling and simulation guided program decisions following a randomized placebo-controlled single-rising oral dose first-in-man trial of compound A where an undesired transient blood pressure (BP) elevati...
Joint Model of Iron and Hepcidin During the Menstrual Cycle in Healthy Women
The online version of this article (doi:10.1208/s12248-016-9875-4) contains supplementary material, which is available to authorized users.
Species and Gender Differences Affect the Metabolism of Emodin via Glucuronidation
The aim of the present study was to define the mechanisms responsible for poor bioavailability of emodin by determining its metabolism using in vitro and in situ disposition models of the intestine and liver. Liver micro...
Early Drug Discovery Prediction of Proarrhythmia Potential and Its Covariates