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Biowaiver monographs for immediate release solid oral dosage forms: cimetidine
E Jantratid1, S Prakongpan, J B Dressman
1Department of Pharmacy, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand.
Journal of Pharmaceutical Sciences
|March 25, 2006
Summary
A biowaiver for cimetidine immediate-release (IR) products is recommended, simplifying drug approval. This waiver for in vivo bioequivalence (BE) testing is based on cimetidine
Area of Science:
- Pharmaceutical Sciences
- Drug Development
- Regulatory Science
Background:
- Cimetidine is an immediate-release (IR) solid oral dosage form.
- Regulatory agencies consider waivers for in vivo bioequivalence (BE) testing to streamline drug approvals.
- The Biopharmaceutics Classification System (BCS) categorizes drugs based on solubility and permeability.
Purpose of the Study:
- To review literature data supporting a waiver of in vivo bioequivalence (BE) testing for cimetidine IR products.
- To evaluate cimetidine's suitability for a biowaiver based on its Biopharmaceutics Classification System (BCS) class, therapeutic index, and excipient interactions.
- To determine conditions under which a biowaiver for cimetidine can be recommended.
Main Methods:
- Literature review of existing data on cimetidine.
- Assessment of cimetidine's classification within the Biopharmaceutics Classification System (BCS).
- Evaluation of cimetidine's pharmacokinetic properties, therapeutic index, and potential excipient interactions.
Main Results:
- Cimetidine is classified as a Biopharmaceutics Classification System (BCS) Class III drug.
- No significant bioavailability (BA) or bioequivalence (BE) problems were reported for cimetidine.
- Data suggests a low risk of excipient interactions with cimetidine.
Conclusions:
- A biowaiver for cimetidine IR products is recommended.
- The biowaiver is contingent upon the test product using specific, commonly reported excipients in usual amounts.
- Both test and comparator products must meet the "rapidly dissolving" criteria as defined by the BCS.
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