Regulatory Open Forum

This message was posted by a user wishing to remain anonymous

I have a question regarding sterility testing for a large volume parenteral. Based on the batch size we need to test six bags of each 500 ml. Should we test each bag separately as six samples for two media tested or combine them and test as on sample? Anyone working with LVPs can suggest. For small volumes such as 1 ml vial we combined them.

Hi Anon,

The Pharmacopeia dictates also the volume of those six bags you have to test. I believe it's 10% of the volume and not less than 20 mL.
As you know, sterility testing does not assure the sterility of the batch. It is a test based on probability. Thus, there is no meaning of define which of the bags is contaminated. You just have to show that all the tested bags are ok. You can combine the bags and take the required amount for testing, as you did for the small volume containers

Hope that helps

------------------------------
Spyros Drivelos
Medical Devices Expert, RAC
Agia Paraskevi, Athens
Greece
------------------------------

Original Message:
Sent: 21-Sep-2020 14:58
From: Anonymous Member
Subject: Sterility testing

This message was posted by a user wishing to remain anonymous

I have a question regarding sterility testing for a large volume parenteral. Based on the batch size we need to test six bags of each 500 ml. Should we test each bag separately as six samples for two media tested or combine them and test as on sample? Anyone working with LVPs can suggest. For small volumes such as 1 ml vial we combined them.

This message was posted by a user wishing to remain anonymous

Thank you Spyros. It is helpful.
Original Message:
Sent: 22-Sep-2020 02:41
From: Spyros Drivelos
Subject: Sterility testing

Hi Anon,

The Pharmacopeia dictates also the volume of those six bags you have to test. I believe it's 10% of the volume and not less than 20 mL.
As you know, sterility testing does not assure the sterility of the batch. It is a test based on probability. Thus, there is no meaning of define which of the bags is contaminated. You just have to show that all the tested bags are ok. You can combine the bags and take the required amount for testing, as you did for the small volume containers

Hope that helps

------------------------------
Spyros Drivelos
Medical Devices Expert, RAC
Agia Paraskevi, Athens
Greece

Original Message:
Sent: 21-Sep-2020 14:58
From: Anonymous Member
Subject: Sterility testing

This message was posted by a user wishing to remain anonymous

I have a question regarding sterility testing for a large volume parenteral. Based on the batch size we need to test six bags of each 500 ml. Should we test each bag separately as six samples for two media tested or combine them and test as on sample? Anyone working with LVPs can suggest. For small volumes such as 1 ml vial we combined them.

Personally, as a scientific question I think the answer is dependent on what you are trying to prove/show/document.  If this is as a release test for the lot, then combining these bags into a single set of tests would be completely acceptable.  As Spyros stated, the fact is that any positive on any bag would thereby fail the lot itself.  When you look at this logically, that makes complete and total sense.  It doesn't matter if there is a single bag that is contaminated or if it is every bag or anything in between.  You aren't going to release the lot, you are going to enter into an investigation and then you are going to have to figure out what happened and how to eliminate whatever the problem(s) identified might be.

If, on the other hand, you are running a media fill or are in the investigation mode, you will want to test individual bags within the lot.  The reason here is simple - if you do combine bags during this process, you are going to have a much more difficult time in understanding where the problem(s) might be if there is any positive test.  With the testing being as it is, it is important to truly and completely understand exactly what your purpose is for performing the test or you are likely to find yourself in a situation where you have data that doesn't provide any relevant or important information.  As an example, if you are in an investigation, if you combine multiple bags then you have multiple variables involved (improper sanitizing of the outside of the bag, poor technique, unknown timepoints involved, etc.) which can often cause additional delays in your investigation as well as the potential to create additional data that needs to be further investigated.  This all leads to having to extend and potentially expand the investigation to other samples and even increase the number of corrective actions.  Additionally, loss of specificity will also cause you to have trouble looking back at records that might have pertinent information for the investigation including potentially time stamped video.  

So really understand what your purpose is before actually running the tests and know what data you are trying to understand before you start designing any experimentation.  Otherwise, you could end up with some odd and mysterious results that you need to do far more work out of it then you probably should need.

------------------------------
Victor Mencarelli
Global Director Regulatory Affairs
MelvilleNY
United States
------------------------------

Original Message:
Sent: 21-Sep-2020 14:58
From: Anonymous Member
Subject: Sterility testing

This message was posted by a user wishing to remain anonymous

I have a question regarding sterility testing for a large volume parenteral. Based on the batch size we need to test six bags of each 500 ml. Should we test each bag separately as six samples for two media tested or combine them and test as on sample? Anyone working with LVPs can suggest. For small volumes such as 1 ml vial we combined them.

This message was posted by a user wishing to remain anonymous

Thank you Victor for the detailed explanation.
Original Message:
Sent: 22-Sep-2020 08:53
From: Victor Mencarelli
Subject: Sterility testing

Personally, as a scientific question I think the answer is dependent on what you are trying to prove/show/document.  If this is as a release test for the lot, then combining these bags into a single set of tests would be completely acceptable.  As Spyros stated, the fact is that any positive on any bag would thereby fail the lot itself.  When you look at this logically, that makes complete and total sense.  It doesn't matter if there is a single bag that is contaminated or if it is every bag or anything in between.  You aren't going to release the lot, you are going to enter into an investigation and then you are going to have to figure out what happened and how to eliminate whatever the problem(s) identified might be.

If, on the other hand, you are running a media fill or are in the investigation mode, you will want to test individual bags within the lot.  The reason here is simple - if you do combine bags during this process, you are going to have a much more difficult time in understanding where the problem(s) might be if there is any positive test.  With the testing being as it is, it is important to truly and completely understand exactly what your purpose is for performing the test or you are likely to find yourself in a situation where you have data that doesn't provide any relevant or important information.  As an example, if you are in an investigation, if you combine multiple bags then you have multiple variables involved (improper sanitizing of the outside of the bag, poor technique, unknown timepoints involved, etc.) which can often cause additional delays in your investigation as well as the potential to create additional data that needs to be further investigated.  This all leads to having to extend and potentially expand the investigation to other samples and even increase the number of corrective actions.  Additionally, loss of specificity will also cause you to have trouble looking back at records that might have pertinent information for the investigation including potentially time stamped video.

So really understand what your purpose is before actually running the tests and know what data you are trying to understand before you start designing any experimentation.  Otherwise, you could end up with some odd and mysterious results that you need to do far more work out of it then you probably should need.

------------------------------
Victor Mencarelli
Global Director Regulatory Affairs
MelvilleNY
United States

Original Message:
Sent: 21-Sep-2020 14:58
From: Anonymous Member
Subject: Sterility testing

This message was posted by a user wishing to remain anonymous

I have a question regarding sterility testing for a large volume parenteral. Based on the batch size we need to test six bags of each 500 ml. Should we test each bag separately as six samples for two media tested or combine them and test as on sample? Anyone working with LVPs can suggest. For small volumes such as 1 ml vial we combined them.

I have to say I agree with Victor's comments.  My first job in this industry was QA Manager for a aseptic fill biologic.  Process validation on the media fills was challenging, and individual vial tests were required.   If it is a lot test, you really better validate that process to show you can combine without contaminating. So easy to do that!


------------------------------
Ginger Cantor, MBA, RAC
Founder/Principal Consultant
Centaur Consulting LLC
River Falls, Wisconsin 54022 USA
715-307-1850
centaurconsultingllc@gmail.com
------------------------------

Original Message:
Sent: 22-Sep-2020 10:55
From: Anonymous Member
Subject: Sterility testing

This message was posted by a user wishing to remain anonymous

Thank you Victor for the detailed explanation.
Original Message:
Sent: 22-Sep-2020 08:53
From: Victor Mencarelli
Subject: Sterility testing

Personally, as a scientific question I think the answer is dependent on what you are trying to prove/show/document.  If this is as a release test for the lot, then combining these bags into a single set of tests would be completely acceptable.  As Spyros stated, the fact is that any positive on any bag would thereby fail the lot itself.  When you look at this logically, that makes complete and total sense.  It doesn't matter if there is a single bag that is contaminated or if it is every bag or anything in between.  You aren't going to release the lot, you are going to enter into an investigation and then you are going to have to figure out what happened and how to eliminate whatever the problem(s) identified might be.

If, on the other hand, you are running a media fill or are in the investigation mode, you will want to test individual bags within the lot.  The reason here is simple - if you do combine bags during this process, you are going to have a much more difficult time in understanding where the problem(s) might be if there is any positive test.  With the testing being as it is, it is important to truly and completely understand exactly what your purpose is for performing the test or you are likely to find yourself in a situation where you have data that doesn't provide any relevant or important information.  As an example, if you are in an investigation, if you combine multiple bags then you have multiple variables involved (improper sanitizing of the outside of the bag, poor technique, unknown timepoints involved, etc.) which can often cause additional delays in your investigation as well as the potential to create additional data that needs to be further investigated.  This all leads to having to extend and potentially expand the investigation to other samples and even increase the number of corrective actions.  Additionally, loss of specificity will also cause you to have trouble looking back at records that might have pertinent information for the investigation including potentially time stamped video.

So really understand what your purpose is before actually running the tests and know what data you are trying to understand before you start designing any experimentation.  Otherwise, you could end up with some odd and mysterious results that you need to do far more work out of it then you probably should need.

------------------------------
Victor Mencarelli
Global Director Regulatory Affairs
MelvilleNY
United States

Original Message:
Sent: 21-Sep-2020 14:58
From: Anonymous Member
Subject: Sterility testing

This message was posted by a user wishing to remain anonymous

I have a question regarding sterility testing for a large volume parenteral. Based on the batch size we need to test six bags of each 500 ml. Should we test each bag separately as six samples for two media tested or combine them and test as on sample? Anyone working with LVPs can suggest. For small volumes such as 1 ml vial we combined them.

When you say you need to test six bags of 500 ml each it sounds to me that you are following a published sampling plan. Can you identify the plan you are using by document number, parameters etc.?

I do a lot of work in acceptance sampling, so I'm interested in the plan.

------------------------------
Dan O'Leary CQA, CQE
Swanzey NH
United States
------------------------------

Original Message:
Sent: 21-Sep-2020 14:58
From: Anonymous Member
Subject: Sterility testing

This message was posted by a user wishing to remain anonymous

I have a question regarding sterility testing for a large volume parenteral. Based on the batch size we need to test six bags of each 500 ml. Should we test each bag separately as six samples for two media tested or combine them and test as on sample? Anyone working with LVPs can suggest. For small volumes such as 1 ml vial we combined them.

This message was posted by a user wishing to remain anonymous

This is for a batch size of 300 and 2% or 10 needed as per USP 71. Sampling plan was as batch begin, middle and end chosen.
Original Message:
Sent: 22-Sep-2020 14:20
From: Dan O'Leary
Subject: Sterility testing

When you say you need to test six bags of 500 ml each it sounds to me that you are following a published sampling plan. Can you identify the plan you are using by document number, parameters etc.?

I do a lot of work in acceptance sampling, so I'm interested in the plan.

------------------------------
Dan O'Leary CQA, CQE
Swanzey NH
United States

Original Message:
Sent: 21-Sep-2020 14:58
From: Anonymous Member
Subject: Sterility testing

This message was posted by a user wishing to remain anonymous

I have a question regarding sterility testing for a large volume parenteral. Based on the batch size we need to test six bags of each 500 ml. Should we test each bag separately as six samples for two media tested or combine them and test as on sample? Anyone working with LVPs can suggest. For small volumes such as 1 ml vial we combined them.

Following USP 71 Table 3, the sample size is the smaller of 10 bags or 2% of the lot size. For this case, the sample size is 6.

Based on USP 71 Table 2, for greater than 100 mL, the test amount is 10% of the contents of the container, but not less than 20 mL. For this case the test amount is 50 mL.

You intend to test with two media.

USP 71 says, "If the contents of each article are of sufficient quantity (see Table 2), they may be divided so that equal appropriate portions are added to each of the specified media".

The USP 71 requirement is to test each article separately in each of the two media. This means twelve tests. I infer that 50 mL provides sufficient quantity for each test from each article. If so, you can split the 50 mL between the two media.

In addition, because you sampled from the beginning, middle, and end instead of a simple random sample, you need to preserve the sample's order for the tests. If the tests reveal a problem, then knowing the order will help determine the cause.

------------------------------
Dan O'Leary CQA, CQE
Swanzey NH
United States
------------------------------

Original Message:
Sent: 23-Sep-2020 20:39
From: Anonymous Member
Subject: Sterility testing

This message was posted by a user wishing to remain anonymous

This is for a batch size of 300 and 2% or 10 needed as per USP 71. Sampling plan was as batch begin, middle and end chosen.
Original Message:
Sent: 22-Sep-2020 14:20
From: Dan O'Leary
Subject: Sterility testing

When you say you need to test six bags of 500 ml each it sounds to me that you are following a published sampling plan. Can you identify the plan you are using by document number, parameters etc.?

I do a lot of work in acceptance sampling, so I'm interested in the plan.

------------------------------
Dan O'Leary CQA, CQE
Swanzey NH
United States

Original Message:
Sent: 21-Sep-2020 14:58
From: Anonymous Member
Subject: Sterility testing

This message was posted by a user wishing to remain anonymous

I have a question regarding sterility testing for a large volume parenteral. Based on the batch size we need to test six bags of each 500 ml. Should we test each bag separately as six samples for two media tested or combine them and test as on sample? Anyone working with LVPs can suggest. For small volumes such as 1 ml vial we combined them.