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Updated: Jun 3, 2026
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Models and Methods to Evaluate Transport of Drug Delivery Systems Across Cellular Barriers
Published on: October 17, 2013
Transporter-mediated drug-drug interactions
L Zhang1, S-M Huang, L J Lesko
1Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland, USA. leik.zhang@fda.hhs.gov
Clinical Pharmacology and Therapeutics
|March 23, 2011
Summary
Drug transporters are proteins that regulate how medications move through the body, impacting their effectiveness and potential side effects. Understanding these transporters is crucial for optimizing drug therapy and minimizing risks.
Area of Science:
- Pharmacology
- Biochemistry
- Molecular Biology
Background:
- Transporter proteins are crucial membrane-bound structures.
- They regulate the passage of endogenous substances and xenobiotics (drugs) within the human body.
- Transporters significantly influence drug pharmacokinetics and pharmacodynamics, affecting both therapeutic benefits and adverse events.
Purpose of the Study:
- To elucidate the role of drug transporters in modulating drug ADME (absorption, distribution, metabolism, excretion).
- To highlight the impact of transporters on drug concentrations at the site of action.
- To emphasize the functional similarities between transporters and metabolizing enzymes regarding saturation, inhibition, and induction.
Main Methods:
- This abstract does not detail specific experimental methods.
- It provides a conceptual overview of transporter function.
- The text implies a focus on the mechanistic understanding of transporter roles.
Main Results:
- Transporters control the access of drugs to various bodily sites.
- They critically affect drug absorption, distribution, metabolism, and excretion.
- Transporter activity influences drug efficacy and toxicity by altering concentrations at target sites.
Conclusions:
- Drug transporters are key determinants of drug disposition and action.
- Their saturable, inhibitable, and inducible nature mirrors that of drug-metabolizing enzymes.
- Understanding transporter mechanisms is essential for rational drug design and personalized medicine.
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