It is understandable that you cannot validate a single rework, so why shouldn’t Q7A be stronger regarding the need to do more intensive testing, including stability testing, on reworked batches? For reworked batches, are stability studies necessary; what instances would require stability studies?

We felt within the expert working group that since reworking is a non-routine activity, and there
are so many possible scenarios under which a company may attempt a rework procedure, it was
necessary to just have a general statement and leave it up to the manufacturer to determine what
testing would be appropriate. But, the bottom line is, and the intent here is that you need to show,
whatever you do, that the reworked API is of equivalent quality to that produced by the original
process. How you do that is really up to you.
Stability testing of reprocessed material was not mentioned because the manufacturer uses the
already accepted process. However in Reworking you introduce a new process and that is why “if
warranted”, is in the document.