title: Causes and Consequences of Variability in Drug Transporter Activity in Pediatric Drug Therapy.
abstract: Drug transporters play a key role in mediating the uptake of endo- and exogenous substances into cells as well as their efflux. Therefore, variability in drug transporter activity can influence pharmaco- and toxicokinetics and be a determinant of drug safety and efficacy. In children, particularly in neonates and young infants, the contribution of tissue-specific drug transporters to drug absorption, distribution, and excretion may differ from that in adults. In this review 5 major factors and their interdependence that may influence drug transporter activity in children are discussed: developmental differences, genetic polymorphisms, pediatric comorbidities, interacting comedication, and environmental factors. Even if data are sparse, altered drug transporter activity due to those factors have been associated with clinically relevant differences in drug disposition, efficacy, and safety in pediatric patients. Single nucleotide polymorphisms in drug transporter-encoding genes were the most studied source of drug transporter variability in children. However, in the age group where drug transporter activity has been reported to differ from that in adults, namely neonates and young infants, hardly any studies have been performed. Longitudinal studies in this young population are required to investigate the age- and disease-dependent genotype-phenotype relationships and relevance of drug transporter drug-drug interactions. Physiologically based pharmacokinetic modeling approaches can integrate drug- and patient-specific parameters, including drug transporter ontogeny, and may further improve in silico predictions of pediatric-specific pharmacokinetics.
authors.affiliation: Pediatric Pharmacology, University of Basel Children's Hospital (UKBB), Basel, Switzerland.
authors.forename: Frédérique
authors.initials: F
authors.lastname: Rodieux
authors.affiliation: Pediatric Pharmacology, University of Basel Children's Hospital (UKBB), Basel, Switzerland.
authors.forename: Verena
authors.initials: V
authors.lastname: Gotta
authors.affiliation: Pediatric Pharmacology, University of Basel Children's Hospital (UKBB), Basel, Switzerland.|Quantitative Solutions/Certara, Menlo Park, CA, USA.
authors.forename: Marc
authors.initials: M
authors.lastname: Pfister
authors.affiliation: Pediatric Pharmacology, University of Basel Children's Hospital (UKBB), Basel, Switzerland.|Division of Pediatric Clinical Pharmacology, Children's National Health System, Washington, DC, USA.|Intensive Care and Department of Pediatric Surgery, Erasmus Medical Center-Sophia Children's Hospital, Rotterdam, The Netherlands.
authors.forename: Johannes N
authors.initials: JN
authors.lastname: van den Anker
mesh_terms: D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D004347:Drug Interactions / Q000502:physiology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D026901:Membrane Transport Proteins / Q000235:genetics* / Q000378:metabolism*; D004364:Pharmaceutical Preparations / Q000008:administration & dosage / Q000378:metabolism*; D011110:Polymorphism, Genetic / Q000502:physiology*
chemical_list: D026901:Membrane Transport Proteins; D004364:Pharmaceutical Preparations
keywords: drug metabolism; drug transporters; individualized medicine; pediatric; pharmacogenetics; pharmacogenomics; pharmacokinetics