Bioequivalence and Bioavailability Forum

Hi everyone,

in the past, we have validated (FDA, EMA) an LC-MS/MS method for simultaneous determination of parent compound and its three metabolites in human plasma.
For internal standard a mixture of all four corresponding deuterated standards was used.

Now, we would like to use this method for determination of parent compound only.
We intend to prepare the CCs and QCs only for the parent compound (no metabolites in the plasma samples), while for the internal standard only corresponding deuterated standard of the parent compound would be used.

Is there any additional cross-validation needed in such case? Any other suggestions?

Many thanks
Marko