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Published on: December 3, 2020
Relative bioavailability estimation of carbamazepine crystal forms using an artificial stomach-duodenum model
Stephen R Carino1, David C Sperry, Michael Hawley
1Pfizer Corporation, Michigan Pharmaceutical Sciences, 7000 Portage Road, Kalamazoo, 49001, USA.
Journal of Pharmaceutical Sciences
|November 30, 2005
Summary
The artificial stomach-duodenum model accurately predicted carbamazepine dissolution, showing Form III > Form I > dihydrate bioavailability. This validated the model for simulating drug release in dogs.
Area of Science:
- Pharmacokinetics and Drug Metabolism
- Pharmaceutical Technology
Background:
- Carbamazepine (CBZ) is a widely used antiepileptic drug with variable bioavailability.
- Understanding the in vitro dissolution of different carbamazepine forms is crucial for predicting in vivo performance.
Purpose of the Study:
- To investigate the in vitro dissolution of carbamazepine (CBZ) using an automated artificial stomach-duodenum (ASD) model.
- To compare the dissolution profiles of different carbamazepine forms (Form III, Form I, and dihydrate).
Main Methods:
- Utilized an automated artificial stomach-duodenum (ASD) model to simulate gastrointestinal conditions.
- Simulated dog physiology in both fasted and fed states.
- Analyzed dissolution profiles and estimated bioavailabilities of different carbamazepine forms.
Main Results:
- The ASD model successfully simulated dog physiology in the fasted state.
- The rank order of estimated bioavailabilities was Form III > Form I > dihydrate.
- Results showed excellent agreement with existing literature data.
Conclusions:
- The ASD model is a reliable tool for predicting the in vivo bioavailability of carbamazepine.
- The study confirms the differential bioavailability of carbamazepine polymorphic forms.
- Further simulations explored the impact of gastric transit times on drug release.
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