Regulatory Open Forum

Hi Ann,

I am not exactly sure of your goal with that testing.
If you want to check sulfadiazine as a preservative of your formulation, USP <51>, Antimicrobial Effectiveness Test is the methodology of choice. This is very common in pharmaceutical preparations and FDA has a lot of guidelines.
If you want to check that your device has antimicrobial properties, there are various standards depending on the application, such as ASTM E-2149, ASTM E-2315 or other tests for biocides such as EN 1040, EN 1276 etc.
FDA had released in the past (2007) a guideline regarding the antimicrobial agents in medical devices, but it was withdrawn in 2015.

Hope that helps

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

Original Message:
Sent: 10-Feb-2020 16:57
From: Ann Kemp
Subject: Antimicrobial Effectiveness

Is there an FDA guidance document on antimicrobial effectiveness testing? I am looking for guidance on testing required for the use of Sulfadiazine with a  hydrogel wound dressing.  

Original Message------

Hi Ann,

I am not exactly sure of your goal with that testing.
If you want to check sulfadiazine as a preservative of your formulation, USP <51>, Antimicrobial Effectiveness Test is the methodology of choice. This is very common in pharmaceutical preparations and FDA has a lot of guidelines.
If you want to check that your device has antimicrobial properties, there are various standards depending on the application, such as ASTM E-2149, ASTM E-2315 or other tests for biocides such as EN 1040, EN 1276 etc.
FDA had released in the past (2007) a guideline regarding the antimicrobial agents in medical devices, but it was withdrawn in 2015.

Hope that helps

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

Hi Ann

Just a comment.. There are those bench tests yes, but clinicals may be required for your dressing, depending on the indications and claims you want to make.  (My experience speaking here from work on Tegaderm CHG, a hydrogel dressing with chlorhexidine gluconate).   It will be considered a combo product, but you know this I am sure.

Assuming you.might consider a pre-sub to flesh out pre-clinical, biocomp, stability, bench, and any clinical study requirements..

PM if you'd like. Best of luck!






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

Original Message:
Sent: 10-Feb-2020 16:57
From: Ann Kemp
Subject: Antimicrobial Effectiveness

Is there an FDA guidance document on antimicrobial effectiveness testing? I am looking for guidance on testing required for the use of Sulfadiazine with a  hydrogel wound dressing.  

Original Message------

Hi Ann

Just a comment.. There are those bench tests yes, but clinicals may be required for your dressing, depending on the indications and claims you want to make.  (My experience speaking here from work on Tegaderm CHG, a hydrogel dressing with chlorhexidine gluconate).   It will be considered a combo product, but you know this I am sure.

Assuming you.might consider a pre-sub to flesh out pre-clinical, biocomp, stability, bench, and any clinical study requirements..

PM if you'd like. Best of luck!






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

All,

I agree with Ginger's comments.  Depending on your indication (and marketing claims), FDA will likely expect in vivo as well as in vitro testing, and against clinical isolates as opposed to ATCC cultures.  They are very keen on real world evidence before allowing a wide ranging antimicrobial claim.  A pre-sub is the best route to guide your regulatory and testing strategy.

James

------------------------------
James Bonds J.D.
Director Regulatory Affairs
Atlanta GA
United States
------------------------------

Original Message:
Sent: 11-Feb-2020 09:00
From: Ginger Cantor
Subject: Antimicrobial Effectiveness

Hi Ann

Just a comment.. There are those bench tests yes, but clinicals may be required for your dressing, depending on the indications and claims you want to make.  (My experience speaking here from work on Tegaderm CHG, a hydrogel dressing with chlorhexidine gluconate).   It will be considered a combo product, but you know this I am sure.

Assuming you.might consider a pre-sub to flesh out pre-clinical, biocomp, stability, bench, and any clinical study requirements..

PM if you'd like. Best of luck!






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

Original Message:
Sent: 10-Feb-2020 16:57
From: Ann Kemp
Subject: Antimicrobial Effectiveness

Is there an FDA guidance document on antimicrobial effectiveness testing? I am looking for guidance on testing required for the use of Sulfadiazine with a  hydrogel wound dressing.  

Ann,

There isn't a FDA Guidance for Industry on antimicrobial (AM) effectiveness nor is there a recognized standard.  However, we have used USP <51> to support preservative effectiveness claims.  Additionally, you may want to refer to the Sep 2016 panel meeting in which FDA discusses antimicrobial claims, i.e. in the meeting FDA discusses hard dressings which can have certain AM claims while amorphous gels can have other very limited claims.  In my experience, a comparison to the predicate device is no longer the litmus test for what is allowed.  Older products can and do have better claims than more recent products...just my 2 cents.

Respectfully,

------------------------------
William Coulston PMP, MS, RAC
Quality & Regulatory Manager
San Antonio TX
United States
------------------------------

Original Message:
Sent: 10-Feb-2020 16:57
From: Ann Kemp
Subject: Antimicrobial Effectiveness

Is there an FDA guidance document on antimicrobial effectiveness testing? I am looking for guidance on testing required for the use of Sulfadiazine with a  hydrogel wound dressing.  

Original Message------

Ann,

There isn't a FDA Guidance for Industry on antimicrobial (AM) effectiveness nor is there a recognized standard.  However, we have used USP <51> to support preservative effectiveness claims.  Additionally, you may want to refer to the Sep 2016 panel meeting in which FDA discusses antimicrobial claims, i.e. in the meeting FDA discusses hard dressings which can have certain AM claims while amorphous gels can have other very limited claims.  In my experience, a comparison to the predicate device is no longer the litmus test for what is allowed.  Older products can and do have better claims than more recent products...just my 2 cents.

Respectfully,

------------------------------
William Coulston PMP, MS, RAC
Quality & Regulatory Manager
San Antonio TX
United States
------------------------------

Hi Ann.

Just to piggy-back onto Spyros's comment - if this is about the effectiveness of sulfadiazine as a preservative of your gel, you need to also account for the following:

1. If the sulfadiazine is embedded in the gel, it is unlikely to fully prevent contamination in general because it is not going to be able to get at the organisms of interest.
2. If this is for use as a preservative, you need to ensure that the gel (when tested) is loose enough to routinely do several things:
  A. it is malleable enough to allow the material to be mixed with the organisms of interest
  B. It remains malleable enough to be sampled at each of the time points.
  C. The organisms being tested can be removed from the material aseptically in order to allow for enumeration.​

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

Original Message:
Sent: 10-Feb-2020 16:57
From: Ann Kemp
Subject: Antimicrobial Effectiveness

Is there an FDA guidance document on antimicrobial effectiveness testing? I am looking for guidance on testing required for the use of Sulfadiazine with a  hydrogel wound dressing.  

I'm not aware of any FDA guidance specific to AET, but you may find FDA's Guidance for Industry Chronic Cutaneous Ulcer and Burn Wounds - Developing Products for Treatment helpful.  There's a section on WOUND-TREATMENT PRODUCT QUALITY MICROBIOLOGY.  I would also refer you to USP <51> ANTIMICROBIAL EFFECTIVENESS TESTING.

------------------------------
Tom
Senior Director, Regulatory Affairs CMC
Chicago
------------------------------

Original Message:
Sent: 10-Feb-2020 16:57
From: Ann Kemp
Subject: Antimicrobial Effectiveness

Is there an FDA guidance document on antimicrobial effectiveness testing? I am looking for guidance on testing required for the use of Sulfadiazine with a  hydrogel wound dressing.  

As mentioned above take a look at the 2016 FRO panel meeting presentation.

------------------------------
Josh Crist
Senior Consultant
Ellicott City MD
United States
------------------------------

Original Message:
Sent: 10-Feb-2020 16:57
From: Ann Kemp
Subject: Antimicrobial Effectiveness

Is there an FDA guidance document on antimicrobial effectiveness testing? I am looking for guidance on testing required for the use of Sulfadiazine with a  hydrogel wound dressing.  

Ann,
Your testing should use species that your device is intended to inhibit. We do a fair amount of these type of submissions and we typically create a testing plan with justified species (depending on where the device is used on the body) and submit this proposal to FDA in a presub.
Hope that helps,

------------------------------
Linda Braddon
CEO
Woodstock GA
United States
------------------------------

Original Message:
Sent: 10-Feb-2020 16:57
From: Ann Kemp
Subject: Antimicrobial Effectiveness

Is there an FDA guidance document on antimicrobial effectiveness testing? I am looking for guidance on testing required for the use of Sulfadiazine with a  hydrogel wound dressing.  

Thanks everyone for the advice. Much appreciated. 

Ann

------------------------------
Ann Kemp RAC, CQA
Consultant
Saint Paul MN
United States
------------------------------

Original Message:
Sent: 12-Feb-2020 09:24
From: Linda Braddon
Subject: Antimicrobial Effectiveness

Ann,
Your testing should use species that your device is intended to inhibit. We do a fair amount of these type of submissions and we typically create a testing plan with justified species (depending on where the device is used on the body) and submit this proposal to FDA in a presub.
Hope that helps,

------------------------------
Linda Braddon
CEO
Woodstock GA
United States

Original Message:
Sent: 10-Feb-2020 16:57
From: Ann Kemp
Subject: Antimicrobial Effectiveness

Is there an FDA guidance document on antimicrobial effectiveness testing? I am looking for guidance on testing required for the use of Sulfadiazine with a  hydrogel wound dressing.