As a fundamental scientific principle, it should be obvious that one should NOT develop or use product-dependent methods or parameters to characterize the product itself. However, this is precisely the practice in the pharmaceutical area for product development and/or its evaluation, i.e., everyone seeks/develops and uses a product-dependent dissolution method.
This is clearly an example of a mindset that is incorrect and scientifically invalid. It appears that the practice of pharmacopeial testing has created this mindset. Most pharmacopeial tests (e.g., USP) are drug and/or product-dependent. However, these should be considered scientifically invalid or useless. If a dissolution test is product-dependent, then it will not be possible to establish whether observed dissolution characteristics are because of the product or due to the experimental conditions used. Therefore, it should be noted that one cannot rely on product-dependent (e.g., pharmacopeial) methods to establish dissolution characteristics of a product, thus its quality.
To evaluate the quality of a drug product, the dissolution method must be product-independent. Therefore, developing product-dependent dissolution methods for any purpose, i.e., QC, discriminatory, bio-relevant, IVIVC, bio-waiver, QbD etc should be considered a mistake and complete waste of time and resources.
At present, a vessel-based dissolution tester with crescent shape spindles (link) has been suggested for product independent dissolution testing. Thus, it provides unbiased and scientifically valid dissolution testing but also helps in saving large resources.