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Population pharmacokinetics of valsartan in pediatrics

Bahru Habtemariam1, William Sallas, Gangadhar Sunkara

  • 1Modeling and Simulation, Navartis, Cambridge, USA. bahru.habtemariam@novartis.com

Drug Metabolism and Pharmacokinetics
|May 12, 2009
PubMed

Insights

This study developed a population pharmacokinetic model for valsartan in children. Age has minimal influence on valsartan clearance when adjusted for body size (fat-free mass).

Area of Science:

  • Pharmacology
  • Pediatric Medicine
  • Drug Metabolism

Background:

  • Valsartan is an angiotensin II receptor blocker used to treat hypertension.
  • Understanding valsartan pharmacokinetics in children is crucial for safe and effective dosing.
  • Interindividual variability in drug response necessitates population pharmacokinetic modeling.

Purpose of the Study:

  • To develop a population pharmacokinetic (PopPK) model for valsartan in pediatric patients.
  • To assess the impact of subject covariates, such as age and body size, on valsartan pharmacokinetics.
  • To optimize valsartan dosing strategies in children.

Main Methods:

  • A single-dose study involving 26 hypertensive children (ages 1-16 years) receiving valsartan.
  • Plasma samples analyzed using liquid chromatography-tandem mass spectrometry (LC/MS/MS).
  • Population pharmacokinetic modeling using allometric scaling and covariate analysis, with a linear 2-compartment model.

Main Results:

  • A linear 2-compartment model with zero-order absorption and lag-time best described valsartan disposition.
  • Both age and body size influenced valsartan clearance; however, body size (fat-free mass) was the primary determinant.
  • Increasing age showed minimal impact on valsartan clearance after accounting for fat-free mass.

Conclusions:

  • The developed PopPK model provides insights into valsartan pharmacokinetics in children.
  • Body size, specifically fat-free mass, is a key covariate for valsartan clearance in pediatric populations.
  • Age-related adjustments to valsartan dosing are likely minimal when body size is considered.

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