Extrapolation of Drug Clearance in Children 2 Years of Age from Empirical Models Using Data from Children

Iftekhar Mahmood1,2

  • 1Office of Tissue and Advanced Therapies (OTAT), Center for Biologics Evaluation and Research, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD, 20993-0002, USA. Iftekharmahmood@aol.com.

Drugs in R&D
|December 11, 2019
PubMed

Insights

Simple empirical models accurately predict drug clearance in young children, outperforming complex models. This research aids in optimizing pediatric drug dosing and safety for children aged two years and younger.

Area of Science:

  • Pharmacology
  • Pediatric Drug Development
  • Biostatistics

Background:

  • Modeling and simulation are increasingly vital in clinical pharmacology.
  • Accurate prediction of drug clearance in pediatric populations is crucial for safe and effective medication use.
  • Existing models often struggle to predict drug clearance in very young children.

Purpose of the Study:

  • To develop and evaluate six empirical models for predicting drug clearance in children aged ≤2 years.
  • Models were derived from clearance data of children aged >2 years and adults.
  • To assess model suitability for preterm infants, term infants, and infants.

Main Methods:

  • Ten drugs with known elimination routes (renal, hepatic, or both) were analyzed.
  • Six empirical models were developed, including age/weight-dependent, allometric, and semi-physiological approaches.
  • Model predictions were compared against observed clearance data in children ≤2 years, with ≤50% prediction error considered acceptable.

Main Results:

  • Three models (body weight-dependent sigmoidal Emax, age-dependent allometric, and semi-physiological) showed acceptable prediction accuracy (>80% observations with ≤50% error).
  • Individual predicted clearance values were often erratic and inconsistent with observed data across most models.
  • Data from 282 children across ten drugs were used for comparison.

Conclusions:

  • Simple empirical models demonstrated superior accuracy in predicting drug clearance in young children compared to complex models.
  • The findings highlight the importance of selecting appropriate modeling strategies for pediatric drug development.
  • Further refinement of predictive models for pediatric drug clearance is warranted.
Abstract

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