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Mind the Gaps: Prioritizing Activities to Meet Regulatory Needs for Acute Systemic Lethality

October 30-31, 2019
Porter Neuroscience Research Center
National Institutes of Health
Bethesda, Maryland, USA

Presentations from the workshop will be available on this page by December 2.

Final agenda (October 29)

Acute systemic toxicity tests are the most commonly performed type of safety test worldwide. Participants in this workshop considered approaches available to assess acute lethality associated with chemicals and chemical mixtures, with the purpose of designing comprehensive strategies to predict toxicity while avoiding animal tests. The specific areas for discussion included:

  • Defining how to calculate the LD50 of a chemical mixture/formulated product
  • Identifying gaps where model (or assay) development or optimization is needed
  • Understanding regulatory needs for model (or assay) outputs
  • Pinpointing the types of mechanistic information that would be useful
  • Establishing the feasibility of using artificial intelligence in model development

Group discussions focused on issues specific to particular classes of chemicals, mechanisms of acute toxicity, prioritization of activities, and recommending next steps. Follow-up actions include an analysis of variability in the in vivo test to establish confidence in toxicity predictions, a comprehensive assessment of an additivity equation for predicting mixtures toxicity, and exploring the addition of biological and mechanistic information to complement in silico predictions.

The workshop was organized by NICEATM and the Physicians Committee for Responsible Medicine.