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Early human ADME using microdoses and microtracers: bioanalytical considerations
Stephen R Dueker1, Peter N Lohstroh, Jason A Giacomo
1Vitalea Science Inc., 2121 Second Street, B101 Davis, CA 95618, USA. srdueker@vitaleascience.com
Bioanalysis
|November 19, 2010
Summary
Accelerator mass spectrometry enables sensitive detection of carbon-14 (14C) drug metabolites using lower radioactivity doses. This advance facilitates early-stage drug development by improving the quantification of drug metabolism and disposition in humans.
Area of Science:
- Pharmacokinetics and Drug Metabolism
- Analytical Chemistry
- Radiopharmaceutical Science
Background:
- Quantitative assessment of drug metabolites in early development is challenging due to the lack of available methods and standards.
- Radiocarbon ((14)C) labeling is crucial for metabolite quantification but traditional detection methods require high radioactivity doses, limiting early use.
- High doses and costs associated with (14)C tracers have historically hindered routine application in drug metabolism and disposition studies.
Purpose of the Study:
- To introduce Accelerator Mass Spectrometry (AMS) as a solution for sensitive metabolite quantification in early-phase drug development.
- To describe empirically based approaches for regulated bioanalysis using AMS with trace (14)C-labeled drugs.
- To provide perspectives on current applications and future opportunities for AMS in drug metabolism research.
Main Methods:
- Utilizing Accelerator Mass Spectrometry (AMS) for the detection and quantification of (14)C-labeled drug metabolites.
- Employing trace levels of (14)C-labeled drug candidates to minimize radioactivity exposure.
- Developing and applying empirically based bioanalytical approaches for regulated studies.
Main Results:
- AMS achieves attomole-level sensitivity, enabling matrix-independent quantitation of metabolites in small samples.
- The technology significantly reduces the required radioactivity levels compared to traditional decay counting methods.
- Early insights into human drug metabolism and disposition are now obtainable in ways previously impractical.
Conclusions:
- Accelerator mass spectrometry overcomes the limitations of traditional (14)C detection, making it feasible for early and routine use in drug development.
- Trace (14)C labeling combined with AMS offers a powerful tool for sensitive and cost-effective metabolite analysis.
- This approach facilitates a deeper understanding of drug metabolism and disposition early in the clinical development process.
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