Until Labs

Sep 26, 2025

Join the club for FREE to access the whole archive and other member benefits . Until Labs raises $58M to push boundaries of cryopreservation Startup scaled cryopreservation from neural slices to large-animal organs, eyeing human trials 23-Sep-2025 Key points from article : San Francisco–based cryonics startup Until Labs, co-founded by Laura Deming and Hunter Davis, has raised $58 million in Series A funding, bringing its total to over $100 million. The company, formerly known as Cradle, is building technology for reversible cryopreservation—the ability to safely pause and restart biological systems. Its immediate goal is to transform organ transplantation by dramatically extending the short window of time in which donated organs remain viable. Currently, donor hearts, lungs, and livers must be transplanted within 4–12 hours, while kidneys last little more than a day. These constraints force urgent logistics, leave many patients waiting in hospitals, and cause thousands of usable organs to be discarded each year. Until Labs is tackling this challenge by developing perfusion systems, new cryoprotective molecules, and rapid rewarming tools that could preserve organs for far longer periods without loss of function. The company reports progress from small tissue samples to large-animal organs and is refining protocols to maintain organ quality after thawing. While organ preservation is the near-term focus, the startup’s ambitions reach further: whole-body reversible cryopreservation. Early work has shown restored electrical activity in thawed rodent neural tissue, and the roadmap includes human organ trials, cryopreserved animal models, and eventually the possibility of pausing and restarting whole organisms. Such advances could reshape transplant medicine, neuroscience research, drug development, and even open the door to medical hibernation or preserving terminally ill patients until future therapies exist. For now, Until’s founders emphasize the practical impact—ensuring that every viable donor organ can reach the patient who needs it. Yet the infrastructure they are building points to a future where medicine might not only extend human life but also temporarily suspend biological time itself. Latest blog posts: