1 

### UDM/OECD Technical Workshop

– Highlights from the Regulatory Sessions ( November 15 th



### , 2011 : Post Registration Testing, AOAC Committee M, etc)

Method/ Activity Aspect Suggestion/recommendation

Regulatory Overviews Front End Process for the Antimicrobial Testing Program See PowerPoint presentation entitled “2011 UDM/OECD Technical Workshop/Post

- Registration Testing”, Joan Harrigan

- Farrelly Group discussed product receipt, chain of custody, development of test parame ters Suggestion made to have company include a “test parameter” chart in future data submissions. Inquiry on process for responding to AD regarding products that registrants believe were tested using incorrect parameters. Registrants are to contact AD.

Re solution may involve sending in new sample. In many cases, the data used to develop parameters were very old. AD and BEAD have listened to concerns of industry and

have re

- evaluated some products already. Suggestion made to adjust performance standards fo r the AOAC Germicidal Spray Products as Disinfectants test as

well.

EPA has limited resources. Resources are being directed

to furthering the OECD method for determining efficacy of hospital disinfectants. EPA encourages industry lab

involvement in terms of volunteer labs for collaborative

studies.

A ction Item

- C SPA to present the option of providing the test parameters for products to members

for consideration

AOAC Committee M Meeting See PowerPoint presentation entitled “AOAC Committee M/September 2011/Annual Meeting”, Dan Klein. Question was raised about AOAC support once the EPA

contract with AOAC expires (July 2012) . Industry may2 approach AOAC.

EPA Method Revision

Activities See PowerPoint presentation entitled “Modifications to Existing AOAC Official Methods”, Jafrul Hasan.

Status of Clostridium difficile Agency presented the data on C. difficile spore preparation protocol and media study

– refer to the Power Point presentation on this topic, entitled “An Update on EPA’s Initiatives and Activities of AOAC Expert Review

Panel on Clostridium difficile : Is C. difficile Becoming Less Difficile?”, Jafr ul Hasan. Inquiry on how the Agency was conducting post registration testing of C. difficile claims. Agency is following the registrant protocol incorporating any scientifically sound changes when there is data (for example, use of appropriate recovery m edia for

enumeration

– recovery media data developed, submitted, reviewed and accepted by the AOAC Expert Review Panel). What will Agency do if data indicates that different chemistries may require different spore/media combinations. Currently few acti ves are registered so this has not been an issue to date Agency will review on a case by case basis.

Recommendation to do a multi

- lab study of spore preparation protocol coupled with efficacy testing using a

few actives. Min/max carrier counts need to b e defined. The performance standard is defined in EPA’s interim guidance for C. difficile claims.3 Quantitative Petri Dish Method (QPM) Agency presented the QPM method using Power Point presentation entitled “ASTM Work Item 32908: Standard

Test Method for Quantitative Petri Plate Method (QPM) for Testing Antimicrobial Towelette Products”, Jafrul

Hasan. The issue of a requirement for a Scientific Advisory Panel review was raised. Suggestion by industry that if an SAP is required for the QPM that it be coupled with

the OECD method. Clarification requested on the scraping procedure

– the procedure was reviewed with the me eting participants. Issue of spreading the inoculum was raised (per discussion at the 2011 AOAC Annual Meeting). The preferenc e by the Agency in order to ensure uniformity across all labs and tests is to dispense the inoculum without spreading due to inconsistency in drying, removal

of inoculum etc. Discussion on impact of pressure applied during wiping, from analyst to analyst. Method indicates to apply4 Quantitative Petri Dish Method (QPM) moderate and gentle pressure. May need to further refine language and technique, but group agreed that this

method was better than the current methodology. In developing current proposed method, towelette workgroup (members from Agency, industry, and testing labs) considered evaluating the active ingredient separately from the towelette and the expressed liquid.

Pr esented the proposal to industry and the response was that evaluating the liquid separately from the wipe was

inconsis tent with how the towelette is used by the consumer. Efficacy is based on both physical (wiping) and chemical (active ingredient) action. The carrier counts should be within a log of the performance standard for the QPM. For example, if the Agency consid ers a five log standard, the carrier count range should be between 5.5 and 6.5 log.

Comment

– Current methodology and proposed QPM method do not take into account wipe label directions that indicate to wipe surface multiple times if necessary to keep wet f or the duration of the contact time. Wipe test should reflect product label directions.

AOAC GSPT Revisions See PowerPoint presentation entitled “Improvements to the AOAC Germicidal Spray Products as Disinfectants

Test

- A Carrier Enumeration Procedure and Establishment of a Log Density Range for Test Microbes on Inoculated Carriers”, Jafrul Hasan. Agency presen ted a method for determining carrier

counts for the AOAC GSPT, and a proposal to establish a carrier count range (5 to 6.5 logs) based on historical data collected by 4 labs over 11 years. Agency will propose procedural revision to method5 AOAC GSPT Revisions 961.02 to include carrier enumeration method and carrier count range for S. aureus and P. aeruginosa

. Persistence data presented in the PowerPoint was developed using organisms ( S. aureus and P. aeruginosa ) grown in nutrient broth.

Comment

– More data may need to be developed to determine impact of using synthetic broth on carrier counts and persistence. Procedural changes for S. enterica to be considered at a

later time

UDM Data EPA presented data on maximum carrier count proposal, UDM collaborative data, reassessment of the performance standard, and the schedule of activities. Refer to the Power Point presentations entitled “Establishment of Maximum Log Density Value for Test Micro bes on Inoculated Carriers,” “Reassessment of UDM Performance Standard,” and “Updated Revision Schedule”; Stephen Tomasino.

Comment

– valuable to have this workshop

– industry suggested future workshops on the spray and towelette methods. Suggestion mad e to have an industry lab lead a workshop as well. Action Item

– CSPA to discuss with

their members. Request made to have a copy of the chart outlining the

UDM method modifications and schedule. Action Item

– the chart was posted to the docket.

Conf idence around the registration versus post registration testing. Registration requires 3 different lots; one aged. Post

- registration will require 1 lot, three replications using separate test cultures. Statistics should bring it to the same point.6 UDM Data Dec ision tree for three replications for post

- registration testing

– if any one test fails to meet the performance standard, the product efficacy will be deemed a failure. Staphylococcus will be run first; then Pseudomonas . All replications can be done in one lab. This is easier logistically and within lab variability is typically less than between lab variability. The Agency will act upon any “red flags” in post

registration testing (e.g., product passes one day with 0+ carrier sets and fails the next day wi th 30+ carrier sets). The industry suggested that if a product fails the first of three tests, the Agency should automatically proceed with the second test to be assured that the product fails consistently. Inquiry about distribution of current ATP data

– pie chart

was shared

– the data is not broken out by test method but EPA will work on doing so. Changes in post

- registration testing requirements and performance standards are meant to be an interim measure during the OECD method implementation phase.



### UDM/OECD Technical Workshop

– Highlights from Regulatory Sessions

(November 16 th 

### , 2011: OECD Method)

11/16/11

OECD Regulatory Overview
Q&A Session on

Reassessment of UDM

Performance Standards Stephen Tomasino reiterated the performance standard proposal for the AOAC UDM (presented 11/15/11) and answered a variety of questions from the audience. Implementation of the new performance standard and changes to post

- registration testing will be transparent

. Comment

– The confidence level resulting from testing three separate lots of product (registration requirement) may be higher than testing one lot of product three times (proposal for post

- registration testing). Some registrants7 create three distinct batches of p roduct for testing, in which the product ingredients are from differing batches. EPA is exploring the possibility of posting draft versions of performance standard

- related papers on the docket

concurrent with AOAC review.

Overview of the OECD

Harmonizat ion Effort See PowerPoint presentation entitled “Overview of the OECD Harmonization Efforts,” Michele Wingfield. Ring trial did not include work on S. enterica because it

is more sensitive to disinfectants than P. aeruginosa

. Agency is not likely to do an y work on S. enterica

. T he Agency committed to communicat ing with the states regarding the harmonization efforts.

Implementation Strategy Agency presented information on the OECD implementation strategy, performance standards, default test conditions, and a timeline for transition. Refer to the Power Point presentation entitled “OECD Implementation Strategy”, Michele Wingfield.
Question aro se regarding how CSPA could best assist EPA with implementation efforts. The Agency responded that industry can help by participating in the upcoming collaborative study and providing suggestions and feedback on the OECD implementation process. Proposed s tandardized contact time of hospital

disinfectants in the OECD method is 5 minutes. The OECD method includes an option for testing s pray products . The p roduct is sprayed into a sterile vessel. The liquid is collected and used for testing.

There will be no bridging study for towelette

- based products. Agency would most likely use the QPM for testing of towelettes. Question regarding submissions for DCI. The Agency will evaluate DCI plans with respect to the proposed changes to the performance standard. Fo r submission of8 data in response to a DCI, the a ge of data cited is not important. What matters is that data meets today’s scientific standards (e.g., the elements present in the

latest version of the AOAC UDM and adequate carrier counts).

Lunchtime Discussion of OECD Collaborative Study Proposed Collabortive Study

of the OECD Bactericidal

Method See PowerPoint presentation entitled “Collaborative

Evaluation of the Draft OECD Test Guidelines for Bactericidal Activity,” Stephen Tomasino. S. Tomasino pr esented the general study plan, timeline, and potential outcomes for the collaborative study.