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October 2019


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Michael Barton <[log in to unmask]>
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The Pharmaceutical Microbiology Forum Email List <[log in to unmask]>
Tue, 8 Oct 2019 11:20:49 +0000
text/plain (42 lines)
Hi all,
what are peoples thoughts on when you can or can not perform a re-test following obtaining an Atypical or OOS result for a finished product?

Would you say that a re-analysis/re-test (from the same starting sample(s) e.g bottles/sampled material in a container) is for additional information only to support a decision or if the result is then within specification it can be used as a final result and initial result was incorrect (i think that that is not the expeceted, as you are not clearly justifying not using teh original result).

I have previously heard that it is reasonable to assume that the filled product with any contamination may not be homogenous and therefore you may not be able to obtain repetitive results and confirm one way or another?
however if we do say that contamination within the batch is not homogenous, how is it reasonably practical to allow us to take such small samples for testing and release on the basis of a satisfactory result  if it is understood that some of the batch we dont test could be contaminated and possibly OOS?

Do we need to assume that our products are homogeneous?  Any references to guidance documents/presentations would be appreciated.

Thanks Mike.

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