Module 2: How to Customize the Screening Funnel for Safety Assessment
Recorded On: 02/19/2026
Clinical stage attrition is detrimental to patients and expensive for the pharmaceutical industry. In the past decade, effort has been made to develop, define, and implement a drug discovery toxicology paradigm to deliver the best development candidates by failing early and cheap unfavorable compounds. The drug discovery process involves a multistep toxicology screening funnel that filters potential drug candidates through increasingly complex and costly stages—starting with thousands of compounds and narrowing down to one approved drug. It begins with in silico (computer-based) screening to predict activity and toxicity, followed by in vitro (cell-based) high-throughput assays for basic toxic effects. Compounds that pass move on to more advanced in vitro testing. In the later preclinical stage, in vivo (animal) testing and safety pharmacology evaluate effects on organ systems. This funnel approach improves cost and time efficiency, allows for early risk identification, optimizes resources, and integrates various testing methods to build a comprehensive safety profile for drug candidates.
Key:
Complete
Next
Failed
Available
LockedYvonne Will, PhD, ATS
SCIENTIA-Consultants LLC
Dr. Yvonne Will is an independent consultant specializing in nonclinical drug safety, discovery toxicology, and the strategic application of new approach methodologies (NAMs) to support decision-making and regulatory readiness in drug development. Through her consulting practice, SCIENTIA-Consultants LLC, she advises biotechnology and pharmaceutical companies on predictive safety strategies, mechanistic toxicology, and fit-for-purpose nonclinical programs from early discovery through IND/CTA-enabling stages.
Dr. Will brings more than two decades of experience in global pharmaceutical R&D, having previously held senior leadership roles including Vice President of Nonclinical Drug Safety and Toxicology at Crinetics Pharmaceuticals, Global Science and Technology Lead for Drug Safety at Pfizer, and senior positions in predictive and investigative toxicology at Janssen (Johnson & Johnson). Across these roles, she has led multidisciplinary teams, shaped nonclinical safety strategy, and advanced the integration of human-relevant in vitro and mechanistic models into discovery and development workflows.
Her scientific expertise spans mitochondrial toxicity, liver safety, cardiovascular risk assessment, mechanistic toxicology, and the design of tiered screening funnels that integrate NAMs within a regulatory-aligned weight-of-evidence framework. Dr. Will is widely recognized for her thought leadership in modernizing toxicology and bridging the gap between cutting-edge science and regulatory expectations.
Dr. Will is actively engaged in the toxicology community and has served in leadership roles within the Society of Toxicology, including as President of the Drug Discovery Specialty Section. She has contributed extensively to the scientific literature and serves on editorial boards for journals focused on applied and translational toxicology.
She holds a PhD and MS in Biochemistry and Biophysics from Oregon State University and a BS from the University of Bonn.