Here Guidance means: Drugs Guidance for Industry – Dissolution Testing and Specification Criteria for Immediate-Release Solid Oral Dosage Forms Containing Biopharmaceutics Classification System Class 1 and 3 (July 2015, Link)
It is difficult to clearly recognise the target audience for the Guidance. However, considering the description “This guidance establishes standard dissolution methodology and specifications that are appropriate for BCS class 1 and class 3 drugs in IR dosage form”, it may be assumed that its target audience is the analytical section/department of a manufacturer or manufacturing facility. So, validity and applicability of the Guidance should only be evaluated considering principles of analytical chemistry. In this regard, the following comments may be considered.
Presumably the objective is to establish a standard methodology; however, suggestions are of multiples. As the in vivo link or relevance of testing is not the focus, then it would be more practical and simpler to just have one set of experimental conditions: e.g. 500 mL of medium (0.01 M HCl or 250 mL which is considered more appropriate as per the guidance) using paddle method set at 75 rpm only with a tolerance of 15 minutes. This will meet the objective of “standard dissolution methodology” better for the Guidance.
From an analytical chemistry perspective, it is important to describe the fact clearly to avoid current misunderstanding that the suggested tester (paddle) is not a validated tester (not GMP compliant) to reflect dissolution characteristics of the products for human use. Therefore, the suggestion/recommendation described should be considered as a regulatory compliance requirement only, and the results/data obtained should not be extrapolated to reflect products’ in vivo behaviour and/or quality attributes for humans.
