Hi everyone,

can someone explain to me, why is the limit for N-nitroso-duloxetine 100 ng/day, because from structure I can calculate that the Potency score = 1, which lead to the limit of 18 ng/day (with CPCA calculation). Meybe I don´t see something in structure or am I missing something?

Thank you all for the answers.


Xetines in general are a clear example of the use of a surrogate (NNK) instead of the CPCA and what the regulators did.

Note: If you look the FDA guideline for example Atomoxetine was defined based on CPCA Category 1

Moving a CPCA limit to surrogate is not automatic and will need approval from HA.

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