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ICCVAM Biennial Report 2018-2019

Biennial Progress Report 2018-2019 Interagency Coordinating Committee on the Validation of Alternative Methods

Collaborative Modeling Project for Androgen Receptor Activity (CoMPARA)

EPA established the worldwide CoMPARA consortium to develop computational approaches to screen chemicals for their potential androgenic activities. CoMPARA followed the approach used for CERAPP (Mansouri et al. 2016).

Regulatory requirements to screen chemicals for potential endocrine disrupting activity are being addressed via HTS approaches and computational modeling. CoMPARA (Mansouri et al. 2020) brought together scientists from 25 international groups, who contributed 91 predictive QSAR models to predict androgen receptor binding, agonist, and antagonist activity. Models were evaluated using literature data extracted from different sources and curated for quality. To overcome the limitations of single-model approaches, CoMPARA predictions were combined into consensus models that provided averaged predictive accuracy of approximately 80% for the evaluation set. These consensus models have been implemented into the free and open-source OPERA application to enable new chemicals of interest to be screened. The entire EPA DSSTox (Distributed Structure-Searchable Toxicity) database of ~750,000 chemicals was virtually screened. Predicted androgen receptor activities have been made available on the EPA CompTox Chemicals dashboard and in the Integrated Chemical Environment.