Similar C-t (plasma drug concentration-time) profiles or BA/BE (bioavailability/bioequivalence) shows that the products (tablets/capsules) provide similar dissolution characteristics (all other things being equal). Therefore, for all practical purposes the C-t profiles or BA/BE studies are the measure of in vivo dissolution characteristics of the products. Thus, by definition, assessment of in vivo dissolution becomes a product assessment/development tool while the same assessment tool becomes a quality control/assurance tool as well. It is scientifically and logically incorrect to separate or differentiate dissolution tests on the basis of their use, i.e. as a product assessment/development tool and a “quality” control/assurance tool. The dissolution test remains exactly the same in both cases.
The same BA/BE test can be, and are, used during the product development stage as well as for comparing the performance of different batches of the same product. The BA/BE test does not change with the stages of product development and manufacturing.
Considering ethical reasons (testing in humans), cost and time, BA/BE tests can neither be conducted, nor conducted routinely, but only for confirmatory purposes. However, for all other purposes such assessments (during product development stage and as a quality control tool during manufacturing of products) dissolution characteristics of a product are evaluated by in vitro dissolution tests. For all practical purposes current drug dissolution tests are indeed used as a substitute of BA/BE, including for QC purposes such as pharmacopeial tests. Therefore, by definition dissolution tests conducted as recommended, are indeed bio-waivers. One does not require any further or special step to transfer a dissolution test to a bio-waiver status or vice versa. Stating otherwise would not change the reality or the fact.
If a dissolution test does not provide an in vivo relevant outcome, then the issue is with the dissolution test and such a test should not be used any further until corrected. Requiring the use of dissolution tests which do not provide bio-relevant results, for any purpose, cannot be justified on any basis, scientific or logical. It simply confuses reality, science and people, and furthermore hinders efficient product development and manufacturing.
