Validation of HPLC Methods

[pharm2004]

Hii Everyone,
We have developed and validated assay and related substances methods for a drug substances. This methods have different conditions compared to those used at the ASMF holder. Authorities want to that cross validation data for assay and related substances of three drug substance batches should be provided.
The validation study performed for the assay and related substance method .The parameters described here are according to ICH guidelines and include accuracy, precision, specificity, limit of quantitation, linearity, range, solution stability and robustness.
Do I have to perform cross validation?
Is there any guideline about cross validation? How can I explain that cross validation isn't necessary?


Many Thanks

[pharm2004]

Please,can anyone answer my question?

Many thanks

[DR]

Essentially, you have to do this to show that your method is equivalent to the compendial or "referee" method. There is no transitive property of validation for analytical methods.