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Author: Dr. Saeed Qureshi, Ph.D.
Dear regulatory and pharmaceutical scientists, please note that all dissolution tests described in the USP and/or FDA database lack scientific basis and are invalid for assessing any drug product characteristics, including quality. The recommended testers and associated methods have never been validated and/or qualified for the intended purpose. These tests are conducted as a regulatory requirement, which forces people/industry to use the testers and the methods resulting in false claims regarding the quality of products. To be scientifically valid, the tests must be product-independent, and testers must be validated and qualified for testing products for human use. Please pay attention!
The tester must be shown first that it is capable of providing relevant dissolution results of a product with low agitation (stirring) environment i.e. it is capable of providing expected and consistent dissolution results with acceptable variability e.g. 10 % CV or RSD. (Physical or mechanical requirement)
The dissolution results obtained must relate to the physiological release characteristics of the product using a physiologically simulated medium (solvent) i.e. a fast drug-release product to provide faster dissolution results while slow drug-release to provide slower drug dissolution results without changing the experimental/testing conditions i.e. test/tester must be product independent. (Physiological requirement)
Since, none of the currently recommended testers and/or methods, including pharmacopeial and/or regulatory, meets the above mentioned requirements; they cannot be considered as bio- or clinically relevant testers or methods. In addition, since none of the currently recommended testers have been shown to meet condition #1 (above), these cannot be considered capable of providing bio- or clinically relevant tests/methods. Suggesting otherwise would be a scientifically invalid practice or claim.
For further discussion on the topic please follow the link.
