XenoSTART is the preclinical research division of the START network dedicated to advancing translational oncology. XenoSTART develops and maintains one of the world’s most comprehensive collections of patient-derived xenograft (PDX) models, representing a wide range of cancer types and disease stages. Each model is clinically annotated with detailed treatment histories, genomic and histologic characterization, and in vivo drug sensitivity data, enabling researchers to bridge the gap between bench and bedside. Through its close integration with START’s global network of early-phase clinical trial sites, XenoSTART offers unique access to fresh patient tumor tissue, rapid model development, and clinically relevant insights that accelerate drug discovery and development.