The Integrated Approaches to Testing and Assessment (IATA) Case Studies Project allows countries to share and explore the use of novel methodologies in Integrated Approaches to Testing and Assessment within a regulatory context.

One new case that illustrates an assessment workflow based on various types of non-animal test methods was published in 2021. In addition, an updated document that includes considerations of using methods in IATA was also published following the 6^th case study review cycle. Since the project was launched in 2015, a total of 24 case studies and six considerations documents have now been finalised.

What are IATA? 

IATA are pragmatic, science-based approaches for chemical hazard characterisation that rely on an integrated analysis of existing information coupled with the generation of new information using testing strategies.

IATA follow an iterative approach to answer a defined question in a specific regulatory context, taking into account the acceptable level of uncertainty associated with the decision context. There is a range of IATA - from more flexible, non-formalised judgment based approaches (e.g. grouping and read-across) to more structured, prescriptive, rule based approaches [e.g. Integrated Testing Strategy (ITS)].

IATA can include a combination of methods and can be informed by integrating results from one or many methodological approaches [(Q)SAR, read-across, in chemico, in vitro, ex vivo, in vivo] or omic technologies (e.g. toxicogenomics).

Why we use AOPs for IATA?

IATA can include a combination of methods and can be informed by integrating results from one or many methodological approaches [(Q)SAR, read-across, in chemico, in vitro, ex vivo, in vivo] or omic technologies (e.g. toxicogenomics).

Many testing approaches do not result in a mechanistic understanding of the induced toxicity. This is particularly the case with non-animal testing approaches and understanding the relationship between what is tested and the apical toxicity endpoint being predicted. This is one of the reasons why results from novel approaches are not yet widely and consistently used for regulatory decision-making.

An objective and systematic framework is needed to characterise the individual biological and toxicological relevance of novel methods in predicting an adverse effect. The same framework could inform their potential use in combination with other tools and methods to benefit from an integrated approach. The Adverse Outcome Pathway (AOP) concept can be applied as a framework to develop IATA.

Why IATA?

Current regulatory toxicity testing and assessment approaches remain to a large extent based on a checklist of in vivo tests, conducted in accordance with standardised test guidelines or protocols such as OECD Test Guidelines.

While this approach has evolved over the past half century, it is unlikely to efficiently meet legislative mandates that require increased numbers of chemical assessments to be undertaken without a concomitant increase in the use of animals and resources.

New approaches are necessary to close the gap between the number of chemicals in use and the number assessed to date.

IATA based on the AOP concept

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Guidance Document on the Use of the Adverse Outcome Pathways in developing IATA

The objective of this guidance document is to:

• Provide a framework for developing and using integrated approaches for testing and assessment (IATA),
• Describe how IATA can be based on the Adverse Outcome Pathway (AOP concept),
• Provide examples on how AOPs can be used in the development of IATA.

RELATED OECD PROJECTS

• OECD Quantitative Structure-Activity Relationships Project including QSAR Toolbox Cooperative Chemicals Assessment Programme (CoCAP)
• Adverse Outcome Pathways (AOP) including AOP Knowledge Base and Tools
• Test Guidelines Programme

RELATED OECD DOCUMENTS

• IATA Case studies and Consideration documents 
• Overview of Concepts and Available Guidance related to Integrated Approaches to Testing and Assessment (IATA)
• Reporting of Defined Approaches to be Used within Integrated Approaches to Testing and Assessment
• Guidance Document on the Reporting of Defined Approaches and Individual Information Sources to be Used within Integrated Approaches to Testing and Assessment (IATA) for Skin Sensitisation
• Guidance Document for the Use of Adverse Outcome Pathways in Developing Integrated Approaches to Testing and Assessment (IATA)
• Guidance on Grouping of Chemicals 
• Guidance Document on the Characterisation, Validation and Reporting of PBK Models for regulatory purposes
• Guiding Principles and Key Elements for Establishing a Weight of Evidence for Chemical Assessment

Please refer to a list and short description of the mapped guidance documents of the Overview document if you are interested in other organisations or government related documents.

• Strongest aspects of case study
• Uncertainty of case study
• Areas for further development of guidance
• Possibility of the use of case study in other regulatory context

In every review cycle, the approved case studies are published with a considerations document capturing leanings and lessons from the review experience.

Case Studies on Integrated Approaches for Testing and Assessment (IATA)

• Guidance Document on the Reporting of Defined Approaches to be Used within Integrated Approaches to Testing and Assessment

• Guidance Document on the Reporting of Defined Approaches and Individual Information Sources to be Used within Integrated Approaches to Testing and Assessment (IATA) for Skin Sensitisation, Annex 1 and Annex 2 

• BACKGROUND:
  Since IATA related deliverables have been published from different projects, having an opportunity to share the experiences in IATA related projects was thought to be helpful in advancing IATA related work at OECD.
• OBJECTIVE:
  To exchange information on experiences in IATA related activities and to provide opportunity to identify synergies and areas for collaboration between OECD IATA working groups.
• WEBINAR:
  Presented overview of OECD IATA related definitions, overview of current IATA guidance and overviews of 11 OECD IATA related projects.