Verification of Protocol

Hi everyone, i have a question about the verification of the protocol.

I have made the protocol and the recovery, and now im ready to make the verification of the cleaning. My question is if the verification is only aceptable when a batch is in progres or i can simulate it. This is because the plant isnt operating yet.

Thanks a lot.

Jonatan Paez

You can do both. You can ensure the analytical method works by using a recovery of a spiked sample AND obtaining a sample from the manufacturing process after cleaning. This way you ensure that there is no interference that is unique to the process (example; detergent). I call it pre-validation, before the protocol is signed and issued.

Yep, thats a good idea!

And for the DHTS/CHTS is it neccesary wait the begining of elaborations or can i simulate a small batch size? I want to do this because when the elaborations begin will be very difficult to make this tests.

Thanks a lot!

If your cleaning procedure works on a stainless steel coupon which has the drug formulation dried on, it will work on your DHTS/CHTS. So a separate protocol or study is not necessary.

So, you are saying that i can do the DHT/CHT in a stainless steel coupon?
But I have to take into account the different areas of the equipments? I can say this is a worst case because the stainless steel coupon is in direct contact with the air and has more probability to be contaminated that the parts without direct contact with the air? Example, the inner part of a V-Mixer.

Best regards.

You can verify that the DHT/CHT will work using a stainless steel coupon, but you will have to perform them using something that is representative of the process train. Most process trains are stainless steel (>90%) so the results will be comparable. Remember, you can have API magnets (like valve gaskets) but most materials of construction used in the process train are inert (SS, glass, plastic…).

Air has nothing to do with the API unless it is oxidizable in which case you will have stability problems.

I mean at air, because in the CHT (i think) play an important role, but im not sure. Has to have certain min area the materiales that i use? or i can use the same that in the recovery test?

No. But because your molecule may oxidize in air you will have to use TOC as your analytical method (since it will detect fragments). Talk to Sievers/GE since they have swabs and rinses.

Your manufacturing process to make the drug product will have to blanket tanks with Nitrogen gas and the cleaning procedure will have include ‘air drying under pressure’.

Thanks a lot for your help!!!

I have a last question. Is it necesary validate the possible impurities? We only work with oncology and hormonal substances, by the moment. Can i use TLC? Which parameters should i validate?


HPTLC is fine. But, the Maximum Safe Concentration (MSC or carryover) is based on the toxicity of the API, cleaning agents… The ‘Acceptable Daily Dose (a measure of toxicity)’ for a hormone (which is very active) is ‘very very’ low. HPTLC may not achieve this level. Thus, many hormone facilities are dedicated (MSC applies only to shared facilities).

Use current standards listed in Eudralex chapters 3 and 5. Method used must be validated per ICH Q2.

Yes, Im going to use HPLC to quantificate the actives (my limit is arround 180 ng and my LOQ is 35 ng), but i dont know if its neccesary to do that with the impurities, and for that, i think, its a good idea to make a limit test with HPTLC, but the product dont have known impurities, so i dont know how to do that.


The only limit on impurities is the assay for the drug product which is in ICH Q3 (limit is 0.05% of the API’s maximum daily dose). There is limit in cleaning validation. Consider your lucky if there are no impurities.

You can try a generic HPLC method for your impurities. See attached: