Campaign Validation and Concintration

I have 5 strengths of the same product. I want to validate cleaning after a campaign of 10 batches.

Do I need to make 10 batches of the highest strength clean and confirm X3

Or can I make 10 batches of any strength provided they increase in concintration and end with the highest strength?

i.e. is does validating 9 batches low strength + 1 batch high strength x 3 get me to 10 batch campaign o any strength??

Thanks in advance.

Dear Mr Gman,

You have to consider worst case approach. Based on the product (and its strengths) estimate the strength which could pose significant impact to cleaning procedure. In my opinion it should be 10 batches of product with maximum strength as it would lead to highest concentration of contaminant (active ingredient, excipient and/or degradant products) on the equipment. More the amount of contaminant on the equipment, more difficult it is to clean.

For further information please refer to this thread:
http://www.askaboutvalidation.com/forum/showthread.php?t=1838
(Risk analysis for campaigns). I hope you can find your answer.