The two presentations in the video offer clear explanations of how the OECD Test Guidelines Programme operates, the key actors and partners. The second presentation illustrates how a validation body has been actively contributing to the Programme. A number of challenges are also identified moving forward with new approach methods.

1. INTRODUCTION TO THE OECD
TEST GUIDELINES PROGRAMME
Anne Gourmelon
Principal Administrator
OECD Test Guidelines Programme
Environmental, Health and Safety Division

2. OECD Mutual Acceptance of Data system
Test Guidelines Good Laboratory Practice
Mutual
Acceptance of
Data
OECD members and MAD adhering countries
OECD Council Decision
1981
“Tested once, accepted everywhere”
5 sections
190 Guidelines
OECD is a consensus-
based organisation

3. • Working Party of the National Coordinators of the Test
Guidelines Programme (WNT)
– One or more National Coordinator(s) for each member and
MAD adhering country and the European Commission,
nominated by the HoD in the parent Chemicals and
Biotechnology Committee (CBC)
https://www.oecd.org/chemicalsafety/testing/national-coordinators-test-
guidelines-programme.htm
– Business and Industry Advisory Committee (BIAC), own
coordinator
– Non-governmental organisations
• International Council on Animal Protection in OECD
Programmes ICAPO, own coordinator
• European Environmental Bureau (EEB), own coordinator
– Secretariat team (8 staff members, 4 of which full time)
A Working Party to oversee the TG Programme

4. • One annual meeting, usually in April in Paris:
– Approval of Test Guidelines and related documents
– Decisions on new projects proposed by member
countries
– Review of on-going projects on the TGP work plan
– Discussion on programme-related issues
Meetings of the WNT
With regular participation of countries with
observer status:
- People’s Republic of China
- Russian Federation

5. • Advisory Group on Endocrine
Disrupters Testing and
Assessment (EDTA AG)
– EDTA-related methods, approaches,
strategies for both HH and ENV
• Advisory Group on Molecular
Screening and Toxicogenomics
(EAGMST)
– AOP Development Programme
– Omics (reporting formats,…)
Advisory Groups affiliated to the
TG Programme
Reporting
directly to
the WNT
Parent bodies:
WNT and Working
Party on Hazard
Assessment
(WPHA)

6. • Projects are led by member countries
– One or more members can lead a project
– Input/contribution on a voluntary basis
– Projects based on a regulatory need
– Template (SPSF) for project proposals to document:
• Rationale for the proposal, intended product/deliverable
• Regulatory need
• Resources involved, timelines, need for an Expert Group
• Animal welfare considerations
• Intellectual property rights in methods proposed
• Cycle: mid-November proposals are submitted
Projects on the TGP work plan

7. • What is the regulatory need?
• Is the output for one or more countries?
• Is the proposed TG broadly applicable?
(or just for a class of chemicals/a chemical sector)?
• Is the proposed method intended to replace an existing TG?
• What is the validation status of the proposed method?
• What is the action plan and timelines?
• Need for an Expert Group? Meeting needs?
• Are there protected elements? If yes:
– What are they? What type of protection?
– What are the means to ensure broad availability across
countries? FRAND declaration.
• Is the proposed method similar (me-too) to an existing TG?
Information to provide in SPSF

8. • Project proposals (SPSF)
Review of draft documents - Timelines
15 Nov ---- review/comments  15 Jan---responses and proposals revision 28 Feb  WNT April meeting
SPSF
submission
Compilation
of comments
Responses
and revised
proposals by
proposing
countries
Decision by member countries
to include/not the project on
the TGP work plan
Loading of documents on
the WNT community site
(not public) TGP work plan approved and
declassified by the CBC
Published on annual basis
https://www.oecd.org/env/ehs/testing/work-plan-test-guidelines-programme-july-2021.pdf

9. Test Guidelines Programme - workplan
9 projects: mainly on physical-chemical
properties of nanomaterials
12 projects: mainly on aquatic toxicity testing
(fish, invertebrates, plants) and for ED testing
7 projects: half are for nanomaterials testing
30 projects: mostly on non-animal methods
for skin and eye irritation, skin sensitisation,
genotoxicity, developmental neurotoxicity,
immunotoxicity, ED testing
3 projects on biocide efficacy

10. • WNT nominates experts to participate in expert
groups to develop documents
– Includes academic researchers, regulatory scientists,
experts nominated by industry (BIAC), experts nominated
by non-governmental organisations (ICAPO, EEB)
– Expert Groups are active as long as there is a project
relevant to their area on the TGP work plan
Expertise to support the TG Programme
 Genotoxicity testing
 Skin/eye irritation/phototoxicity
 Skin sensitisation
 Non-genotoxic carcinogenicity
 Developmental neurotoxicity
 Immunotoxicity
 Physical-chemical properties of nanomaterials
 Environmental fate of nanomaterials
 Ecotoxicity testing in aquatic/sediment environment
Main active Expert Groups
on multiple/large projects

11. Nature of tools developed in the TG
Programme
Covered my MAD
• Test Guidelines
• Guideline on Defined Approaches
• Combinations of information sources have been individually
evaluated
Other important documents
• Guidance Documents in support of testing and assessment
• Detailed Review Papers in new areas of chemical toxicity testing
• Validation reports
• Peer review reports
Other tools (courtesy of the test developers)
• Excel spreadsheets for raw data collection and calculation sheets
• COTS software

12. Methods described in Test Guidelines typically result from an evaluation of
their relevance and reliability/robustness, using a representative set of
chemicals for which they are intended to be applied
• Any limitations identified are described in the Test Guideline
• Any data transformation (statistical)/interpretation procedure (prediction
model) used in the development of the method and evaluated/accepted by
the WNT, is described in the Test Guideline
• A validation report/supporting document is published showing how the
method performs
– Guidance Document No 34: provide a modular approach to validation of methods
for hazard assessment of chemicals
– Good In Vitro Method Practice No 286: provides instructions on best practice for
any aspects of in vitro methods (development and implementation)
When a method is approved as a (Test) Guideline, regulators are confident in
its relevance and reliability
• These aspects need not be demonstrated each time the method is
subsequently used.
Development of Test Guidelines

13. Process, workflow and timelines for TG-
related project development
SPSF submitted by
lead country(ies)
- 15 November
Expert Group work
on technical aspects
of the Test Guideline
and consensus
building
Meetings/TCs
WNT reviews and
finally approves final
draft document
Committee
(CBC) endorses
TG/GL
If approved,
project starts

14. Test Guidelines team
Anne Gourmelon
Principal Administrator
Nathalie DELRUE, Administrator
Areas covered: genotoxicity,
carcinogenicity, skin sensitization, AOP
Programme
Mar GONZALEZ, Administrator
Areas covered: nanomaterials safety
testing
Leon VAN DER WAL, Administrator
Areas covered: aquatic toxicity,
environmental fate and behaviour
Magdalini SACHANA, Administrator
Areas covered: Developmental
neurotoxicity, AOP Programme
Eugene CHOI, Administrator
Areas covered: skin and eye irritation,
phototoxicity
Yusuke OKU, Administrator
Areas covered: genotoxicity,
carcinogenicity
Carole Guerrier, Programme Assistant

15. Supplementary slide

16. • What is the regulatory need?
• Is the output for one or more countries?
• Is the proposed TG broadly applicable?
(or just for a class of chemicals/a chemical sector)?
• Is the proposed method intended to replace an existing TG?
• What is the validation status of the proposed method?
• What is the action plan and timelines?
• Need for an Expert Group? Meeting needs?
• Are there protected elements? If yes:
– What are they? What type of protection?
– What are the means to ensure broad availability across
countries? Elaborate.
• Is the proposed method similar (me-too) to an existing TG?
Information to provide in SPSF
Rationale to provide for me-too methods
(one or more item should match the proposal):
• No intellectual property restriction/freely available
• Broader geographical availability
• Broader/complementary domain of applicability
• Reduced cost or analysis time
• Reduction in animal/animal product use (e.g. serum)
• Inclusion of inherent metabolic capacity or proven
possibility of combination with metabolising system
• Improved mechanistic insight
• Additional toxicity endpoints (to those covered in the
TG)
• Reduction in hazardous reagents
• Improved predictivity.

17. Reflections on the Test Guidelines
Programme
Tim Singer
Chair, Working Party of the National Coordinators of the Test Guidelines
Programme

18. Working Party of the National Coordinators of the Test Guidelines Programme
2
• The governance body for the Test Guidelines Programme.
• As an entity within the OECD framework, operates on a
consensus basis.
• All decisions are made following extensive consultation.
• National Coordinators (NCs) are the focal point for TGP
activities in their countries and represent their countries at the WNT.
• Small turnover of NCs from year to year, but a core group remains
constant – significant corporate memory within the body and a
high degree of consistency of approach.

19. Key Trends and Observations Regarding the Test Guidelines Programme
• There is a significant user base and now nearly 40 years of experience
with the Test Guidelines as tools supporting sound regulation of chemicals.
• Mutual Acceptance of Data has become indispensable in avoiding
duplication and in establishing scientifically sound methods to
support protection of human health and the environment.
• Animal welfare considerations have grown in importance over the past
10+ years – emergence and acceleration of alternative methods.
• Test Guidelines have become more complex (and longer!) as efforts have
been made to provide more clarity and reduce ambiguity.
• Efforts to address intellectual property and avoid inadvertent monopolies
led to Performance Based Test Guidelines and an explosion of “me-too”
methods for some endpoints.
3

20. Future Opportunities and Challenges for the Programme
• Decisions around resource allocation may necessitate setting priorities – are there areas with
regulatory value that are not yet well covered by Test Guidelines?
• Delicate balance between maintaining transparency about methods used to support regulatory
decision-making and incentivizing innovation among test developers.
• Expansion of Defined Approach-based Test Guidelines to facilitate full replacement of animal
methods where warranted.
• Curation of the library of Test Guidelines – what to do with older and potentially obsolete
methods, or animal methods that may no longer be widely used? Work has started on
approaches here.
• Preserving Mutual Acceptance of Data in light of diverging requirements in certain countries or
regions.
4

21. Concluding Thoughts
• The Programme is well positioned to translate advances in science and method development
into guideline development in support of regulatory needs.
• There is an enormous community of experts that continues to support the Programme,
providing a solid scientific foundation for the future.
• As we continue to support and advance Mutual Acceptance of Data, continued collaboration
with the Working Party on GLP is essential and welcomed.
5

22. 1
Validation in a regulatory
context
Joint OECD WNT-GLP WP meeting
2 December 2021
Valérie Zuang
EU NC

23. 2
1. JRC/EURL ECVAM introduction
2. The definition and principles of validation
3. Novel concepts in the validation of alternative methods
4. Lessons learned (scientific and non-scientific issues)
Overview

24. 3
Science and knowledge service of the Commission
Support EU policies with independent evidence
~ 3000 staff
Almost 75% are scientists
Headquarters in Brussels
Research facilities in 5 EU Member States
The Joint Research
Centre (JRC)

25. 4 4
Directorate F
F.3.
Chemical Safety &
Alternative Methods
Ispra
F.4
Fraud
Detection &
Prevention
F.5
Food & Feed
Compliance
F.1
Health in
Society
F.2
Consumers
Products
Safety
F.6
Reference
Materials F.7. Knowledge
for Health &
Consumer
Safety
Joint Research Centre (JRC), Directorate F: Health, Consumers
and Reference Materials Geel (Belgium) & Ispra (Italy)

26. 5
o Guide research on alternative methods
o Coordinate validation within the EU
o Disseminate information on the 3Rs
o Promote stakeholder dialogue
o Promote international acceptance
Duties and tasks*
* Article 48 of the Directive, Annex VII
European Union Reference Laboratory
for Alternatives to Animal Testing
Established under the Directive 2010/63/EU on the
protection of animals used for scientific purposes

27. 6
EURL ECVAM Validation Process
Research &
Development
Validation
Independent
Peer Review
Implementation
PARERE/ESTAF
ESAC
EU NETVAL
ICATM
ICATM
EU, OECD, ISO,
ICH, VICH,
Pharmacopoeia
EURL ECVAM
Public
Test Submitter
International Recognition /
Regulatory Acceptance
PARERE/ESTAF
EURL ECVAM
Recommendation

28. 7
Overview
1. JRC/EURL ECVAM introduction
2. The definition and principles of validation
3. Novel concepts in the validation of alternative methods
4. Lessons learned (scientific and non-scientific issues)

29. 8
Validation
"The process by which the reliability and
relevance of a particular approach, method,
process or assessment is established for a
defined purpose"

30. 9
PROTOCOL(S)
TEST
METHOD
Relevance:
predictive
capacity
= +
+
Reliability (reproducibility)
Relevance:
scientific basis
TEST
SYSTEM(S)
ENDPOINTS /
BIOMARKERS
PREDICTION
MODEL / DIP
Worth & Balls (2001). ATLA 29, 135-143
Principles and criteria for validation (in a regulatory context)

31. 10
Purpose: applications in regulatory decision making
Mechanistic information Priority setting
Hazard identification Hazard characterisation

32. 11
• Increase confidence in a method by demonstrating its ability to provide
reproducible and relevant data
• Ensure sound science-based decisions are made to protect human
health and the environment
• Facilitate development of globally harmonized standard methods
Validation to build confidence and reach acceptance
− Not an impediment or a constraint
− Acceptance cannot be imposed
Why validation?

33. 12
The Modular Approach to validation
Relevance
Reliability
Reliability
Relevance
Independent
Peer
Review
Hartung et al. (2004).
ATLA 32, 467-472
"No sequential
assessment needed"
Validation
Management
Test definition
Within-lab reproducibility
Transferability
Between-lab reproducibility
Predictive capacity
Applicability domain
Performance standards

34. 13
Serious eye damage/eye irritation:
 BCOP, ICE, HET-CAM; FL, CM
Genotoxicity:
 Micronucleus assay
New
Test Method
Similar
Test Method
Modification of
validated /
approved /
established
Test Method
Established but
non-validated
Test Method
Prospective
Validation
Study
Performance
Standards-based
validation study
Retrospective
Validation
Study
Transfer
test to EURL-
ECVAM and
optimisation if
needed
Update based
on Performance
Standards
ECVAM Validation
Processes
Characteristics
 Prospective multi-
laboratory ring trial
 Validation in reference
to Performance Standards
 Pre-defined Reference
Chemicals
 Normally external studies
 Evaluation based
on existing data
 Typically no testing
 Perhaps several SOPs,
PMs available
Skin corrosion:
 EpiSkin™ SCT, TER
Skin irritation:
 EpiSkin™ SIT, EpiDerm™ SIT
Serious eye damage/eye irritation :
 EpiOcular™ EIT; STE
Skin sensitisation:
 DPRA, h-CLAT, U-SENS;
KeratinoSens
Skin corrosion:
 Epiderm™ SCT; epiCS®;
SkinEthic™ RHE SCT
Skin irritation
 SkinEthic™ RHE SIT;
updated EpiDerm™ SIT
Skin sensitisation
 LuSens
EXAMPLES
Test Method
Types
OECD TG 430
OECD TG 431
OECD TG 431
OECD TG 439
OECD TG 439
OECD TG 492 OECD TG 491
OECD TGs 437, 438, 460
OECD TG 442C, 442E
OECD TG 442D
OECD TG 487

35. 14
Overview
1. JRC/EURL ECVAM introduction
2. The definition and principles of validation
3. Novel concepts in the validation of alternative methods
4. Lessons learned (scientific and non-scientific issues)

36. 15
The modern safety assessment toolbox
DATA
INTEGRATION
PREDICT SAFETY
Exposure modelling
Cheminformatics &
QSAR modelling
Cell cultures
3D tissues
Organ-on-a-chip
High content
imaging
'OMICS
HTS

37. 16
The principles and process of validation
• PRINCIPLES are universal and valid
• PROCESS is adaptable depending on purpose (validation
towards universal acceptance vs. for specific use context)
• One size doesn’t fit all. Process needs to be fit for purpose!

38. 17
Overview
1. JRC/EURL ECVAM introduction
2. The definition and principles of validation
3. Novel concepts in the validation of alternative methods
4. Lessons learned (scientific and non-scientific issues)

39. 18
Workshops on validation
How to evolve
validation
practices?
How to develop
the concept of
standards?
JRC-Ispra, 23-24 October 2018
BfR-IRVM - Berlin, 2017, 2018
How to establish
relevance without
animal data?
How to evaluate
reliability without ring
trials?

40. 19
How to assess RELEVANCE of single methods
TIME and COST constraints
Poor/unknown quality of REFERENCE DATA
Too high focus on "GOLD STANDARD" and PREDICTIVE
CAPACITY
Poor CHEMICALS SELECTION introducing bias
Lab specific SOPs that hinder transferability
Lessons learned: scientific issues

41. 20
Restrained by REGULATORY REQUIREMENTS
ENGAGEMENT with stakeholders at every step
Tackling INTELLECTUAL PROPERTY (ensuring commercial
availability & avoiding abuse of monopolies)
Lack of TRANSPARENCY of protected elements
GLP IMPLEMENTATION of protected elements and
cloud-based computerised systems
Lessons learned: non-scientific issues

42. 21
Final thoughts
• Validation will remain one of the cornerstones of a successful toxicological
(r)evolution
• Validation needs to keep pace with rapid scientific progress, e.g. DAs,
computational models, Organ-on-Chip
• Important to maintaining scientific integrity, credibility and usefulness while
making process more efficient
• Frame validation as a process to characterise and reduce uncertainty rather than
a ring trial to demonstrate "toxicological equivalence"

43. 22
Keep in touch
https://ec.europa.eu/jrc/en/eurl/ecvam
@EU_ScienceHub #ECVAM
News from EURL ECVAM
You can find me at valerie.zuang@ec.europa.eu