Extracellular Vesicles as Enabling Biomarkers for New Approach Methodologies to Support the US Food and Drug Administration Modernization Act 3.0.

The FDA Modernization Act 3.0 represents a pivotal shift in biomedical research by formally removing the requirement for animal testing and enabling regulatory acceptance of New Approach Methodologies (NAMs). This transition creates an urgent need for robust, human-relevant biomarkers that can anchor NAM-generated data within regulatory decision-making, particularly for first-in-human studies. Extracellular vesicles (EVs), owing to their biological stability, accessibility and rich molecular cargo, may be well positioned to fulfil this role. EVs reflect dynamic cellular states and intercellular communication, making them mechanistically informative readouts of pharmacology, toxicity, immune modulation and disease biology across human-derived model systems. This Perspective outlines how EV-based biomarkers can support the qualification, standardization, and regulatory acceptance of NAMs, with particular emphasis on ex vivo platforms such as organoids, microtissue systems, organ-on-chip devices and perfused tissue slices. We highlight the advantages of EVs for longitudinal, non-destructive sampling, representation of human variability, and integration with quantitative systems pharmacology and physiologically based pharmacokinetic models. Finally, we discuss the scientific, operational and regulatory challenges that must be addressed and argue that coordinated leadership from the International Society for Extracellular Vesicles (ISEV) is essential. The convergence of regulatory reform and EV science presents a timely call to action to establish EVs as foundational biomarkers in next-generation, human-centric drug development.