The Department of Health and Human Services, through the National Institutes of Health's Advanced Research Projects Agency for Health (ARPA-H), is announcing a Proposers’ Day for the Computational ADME Tox AnaLYsis for Safer Therapeutics (CATALYST) program, scheduled for October 29, 2024, in Cincinnati, OH. This initiative aims to engage the scientific community in developing AI/ML-enabled in silico human physiology modeling platforms to reduce reliance on animal studies in drug safety assessments, ultimately enhancing drug efficacy predictions and expediting the drug approval process. The CATALYST program is structured in two phases, focusing on technology development and regulatory demonstration, and participation in the Proposers' Day is encouraged for those interested in collaboration, although it is not mandatory for proposal submissions. Interested parties should register for the event and can reach out to CATALYST@arpa-h.gov for further information.