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Updated: Sep 12, 2025
08:59
An Intestine/Liver Microphysiological System for Drug Pharmacokinetic and Toxicological Assessment
Published on: December 3, 2020
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Property-Based Prediction Uncovers Intestinal Excretion as an Elimination Route of Small-Molecule Drugs
Chen Chen1, Weiping Zhao1, Lin Cao2
1Drug Metabolism and Pharmacokinetics, Drug Discovery, Genentech Inc., South San Francisco, California 94080, United States.
Journal of Medicinal Chemistry
|August 8, 2025
Summary
Intestinal excretion is a significant drug clearance route, often overlooked. This study reveals its mechanisms and offers new considerations for drug design and pharmacokinetic assessment.
Area of Science:
- Pharmacology
- Drug Metabolism
- Drug Discovery
Background:
- Hepatic and renal pathways are traditionally viewed as primary drug clearance routes.
- Emerging evidence suggests direct intestinal excretion plays a significant role.
- Intestinal excretion is often underestimated due to unabsorbed drugs and biliary excretion complexities.
Purpose of the Study:
- To investigate the extent and mechanisms of intestinal drug excretion.
- To develop a predictive model for intestinal excretion based on molecular descriptors.
- To understand the interplay between intestinal and biliary excretion pathways.
Main Methods:
- Utilized bile duct cannulated rats for in vivo studies.
- Investigated a diverse library of drugs for intestinal excretion.
- Developed a predictive decision tree using molecular descriptors.
Main Results:
- Passive permeability and efflux transporters are key drivers of intestinal excretion in rats.
- Modifying a single functional group can shift drug clearance between intestinal and biliary routes.
- Identified intestinal excretion as a major pathway for metabolically stable small-molecule drugs.
Conclusions:
- Intestinal excretion is a crucial, yet underexplored, drug clearance pathway.
- Findings provide a more comprehensive understanding of drug clearance mechanisms.
- Offers new considerations for drug design and pharmacokinetic assessment strategies.
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