I’d like to know people’s thoughts on what makes a batch a ‘representative batch’ for stability studies. I think it is straight forward for post-approval stability, but if you’re making batches in R&D, isn’t it more like ‘expected to be representative batch’ – until you’ve collected a good amount of data? Anyway, if you use a list of criteria (same/similar formulation, same process, etc.) to determine what is representative and what is not, I’d be interested in discussing it.
By the way, everything I say here are my own opinions and not necessarily those of my employer.
Are you asking what makes a development batch a potentially representative batch for a material / product that eventually goes commercial or for another development batch or just in general?
That is a fairly general question with a lot of different variables to consider. If you think about formulation, CPPs, CQAs, suppliers, etc. I think it largely depends on what you are comfortable technically justifying and supporting with any appropriate regulations, health authority, USP or other validation / development data as applicable. Wouldn’t it also depend largely also on what your intention was for your lot to be a representative of if not equivalent to? Just thinking you would clearly have more flexibility with A.D. or R&D batches versus registration / commercial.
These are my own thoughts and not those of my employer.