Greening, David W.

ABSTRACT 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.

ABSTRACT The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell‐released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV‐associated functional activities. Finally, a checklist is provided with summaries of key points.