impurity profile study of an API

Dear forum members,
What things has to be considered during impurity profile study of an API, kindly guide on the same


very simple,

test three batches and report the impurities, This is Enough.
during anlaysis check for peak purity of your known impurites along with main peak.

Definition of impurity profile : Description of identified an unidentified impurities

Bujji Reddy Kanchi.

Can you support your comments with a regulatory proof?
I would like to see what document you reffered and would like to read about the consequences later if they do not pass.

Process validation batches gives the proof that batches do not fail.

Impurity profile gives the information of impurities present in the substance.

we submit the impurity profiles to the requlatory agency (Eg: USFDA) .

we take three process validation batches and report the impurities.

I do not have any referene guideline for this that gives clearly about Impurity profiles study must be like this…

If I am wrong, please correct me.

Please send any reference guideline related to Impurity profile other than ICH Q3A,B.

Best Regards,
Bujji Reddy Kanchi.


Impurity: Any component of the new drug substance that is not the chemical entity defined as the new drug substance.

Impurity Profile: A description of the identified and unidentified impurities present in a new drug substance.

Perform the impurity Profiling with the following steps

Identify the impurities present in the Drug substance based on the chemical reactions involved in the synthesis, impurities associated with raw materials that could contribute to the impurity profile of the new drug substance, and possible degradation products.

Based on the Analysis of the Drug substance impurities classify the Actual and Potential impurities and name them.

Step -3
Identify and characterize the impurities which are present greater than the identification thresholds.

Step -4
Perform the 3 batches of drug substance for impurities and give as supporting data.


Dear srikanth and Durga,

Usually we manufacture drugs as per pharmacopeial specifications.

Monographs describes the impurities and its limits. Besides this, Potential impurities greater than Identification threshold are considered as specified Inhouse impurity.

Now The Impurity profile Protocol calls three validation batches analysis and the Report the impurities present in the samples.

Can I get any support guidance for Impurity profile
and your experiences regarding Impurity profiles and regulatory queries.

Thanks for your kind cooperation

Best Regards,
Bujji Reddy kanchi.