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December 2003


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Chad Ronholdt <[log in to unmask]>
Reply To:
The Pharmaceutical Microbiology Forum Email List <[log in to unmask]>
Tue, 16 Dec 2003 14:35:57 -0700
text/plain (56 lines)
Greetings forum members,

My question relates to whether or not it is acceptable to add individual
microbial log reduction steps from a multiple step process into a cumulative
log reduction for your entire process. For example, I have a manufacturing
process that has 5 steps with worse case microbial log reductions of 5, 4,
3, 2, 1, respectively. Therefore, is my overall log reduction for the entire
process 15 logs or is it simply the greatest log reduction demonstrated by
the first step--5 logs?

I have an issue with reporting the 15 log value since that would indicate my
manufacturing process would produce a "sterile" product with some level of
assurance. Clearly, this isn't the case since I use a terminal sterilization
step to obtain the sterile label claim and I have positive sterility
cultures from time to time prior to sterilization.

Any comments or suggestions on how to report the efficacy of my
manufacturing process would be helpful. Thanks.


Chad J. Ronholdt, MBA
Scientific Affairs Manager
6278 S. Troy Circle
Centennial, CO 80111
Ph: 720.873.4782
Fax: 720.873.0212
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