Physiologically based pharmacokinetic model for topotecan in mice
Dhaval K Shah1, Joseph P Balthasar
1Department of Pharmaceutical Sciences, University at Buffalo, The State University of New York, 457B Cooke Hall, Buffalo, NY 14260, USA.
Journal of Pharmacokinetics and Pharmacodynamics
|November 25, 2010
Summary
This study developed a pharmacokinetic model to predict topotecan concentrations in mice, aiding in understanding this ovarian cancer drug's behavior in plasma and tissues.
Area of Science:
- Pharmacology
- Pharmacokinetics
- Computational Modeling
Background:
- Topotecan is a key chemotherapeutic for recurrent ovarian cancer.
- Accurate pharmacokinetic (PK) modeling is crucial for optimizing drug therapy.
- Understanding topotecan distribution and elimination is essential for effective treatment.
Purpose of the Study:
- To develop a physiologically based pharmacokinetic (PBPK) model for topotecan in mice.
- To characterize and predict topotecan plasma and tissue concentrations.
- To evaluate the model's predictive performance across various doses and administration routes.
Main Methods:
- Physiologically based pharmacokinetic (PBPK) modeling approach.
- Intravenous administration of topotecan (5, 10, 30 mg/kg) to male Swiss Webster mice.
- High-performance liquid chromatography (HPLC) for sample analysis; modeling of drug disposition in multiple organs.
Main Results:
- Topotecan exhibited dose-dependent, nonlinear pharmacokinetics.
- The PBPK model accurately characterized topotecan PK in plasma and various tissues.
- Model demonstrated strong predictive accuracy for external datasets across different doses and routes (IV, IP).
Conclusions:
- The developed PBPK model effectively characterizes topotecan pharmacokinetics in mice.
- This model can predict topotecan concentrations, supporting future therapeutic strategies.
- The study highlights the nonlinear nature of topotecan elimination and distribution.
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