XPRIZE Healthspan Executive Director Jamie Justice on judging therapeutics, scaling interventions and navigating regulation.
Twenty teams have reached the final stage of XPRIZE Healthspan, the seven-year, $101 million competition seeking therapeutics capable of restoring muscle, cognitive and immune function lost through age-related decline. Ten have also secured $1 million Milestone 2 awards; from 2026 to 2029, the finalists will move into clinical trials lasting up to one year, testing approaches that range from repurposed drugs and stem cell therapies to genetic interventions, mitochondrial therapeutics and extracellular vesicles.
For XPRIZE, however, selecting promising science is only part of the problem. Therapies must ultimately demonstrate not only efficacy and safety, but the potential to be manufactured, delivered and scaled at a realistic cost; meanwhile, interventions developed across different modalities and jurisdictions must be assessed against sufficiently consistent measures to make comparison meaningful.
Longevity.Technology: Proving that a healthspan intervention works is one problem; deciding what medicine should do with it afterwards may prove another entirely. Geroscience increasingly asks whether intervening in the biology of aging can alter multiple trajectories of age-related decline, yet drug development and regulation remain largely organized around individual diseases – aging itself, despite being the principal risk factor for many of them, is not formally recognized as a therapeutic indication. XPRIZE Healthspan therefore finds itself conducting an intriguing experiment within the experiment: its finalists are competing against common measures of muscle, cognitive and immune function, but a successful intervention could generate evidence for a therapeutic proposition that does not fit particularly neatly within the regulatory architecture waiting for it. XPRIZE cannot solve that problem by fiat, nor should a prize competition determine regulatory policy; it can, however, help generate the standardized human evidence needed to move the conversation forward. To discuss how radically different therapeutics can be judged on common ground and whether the evidence generated by XPRIZE could help shape future regulatory pathways for healthspan interventions, we sat down with Dr Jamie Justice, Executive Director of XPRIZE Healthspan.
The clever bit is only the beginning
The finalist field is scientifically eclectic by design, but XPRIZE is not simply looking for the most technically adventurous intervention. A therapy capable of shifting functional aging in a tightly controlled cohort is one proposition; producing it affordably, delivering it beyond specialist centers and scaling it across populations is quite another.
Justice says that tension between biological ambition and practical deployment is already part of the assessment.
“When judges are evaluating teams, they’re looking at the whole picture, including efficacy, safety, and whether a solution can realistically be manufactured and scaled at a cost that makes sense,” she told us. “Ultimately, the strongest solutions will be those that demonstrate meaningful efficacy while also showing the potential for broad accessibility and global scale.”
Those considerations are not being deferred until a winner emerges. Scientific rationale, scalability, accessibility and readiness for clinical trials all informed the selection of the current finalist cohort; Justice says they will remain central as trials proceed through 2029.
That matters particularly in healthspan, where the addressable population is potentially vast. An intervention that can technically modify aging biology but cannot plausibly escape a rarefied clinical setting may represent impressive science; it is rather less convincing as an answer to population aging.
Comparing apples, oranges and extracellular vesicles
Scale, however, is only useful if efficacy can be established convincingly – and comparing such radically different therapeutic approaches presents a methodological headache of its own. A repurposed drug combination and an extracellular vesicle therapy may both be chasing improved healthspan, but they certainly do not arrive at the starting line carrying identical scientific baggage.
XPRIZE’s answer is to standardize as much of the measurement infrastructure as possible. The University of Utah Data Coordinating Center will oversee centralized data management, while UC San Diego’s Stein Institute for Research on Aging will coordinate centralized laboratory testing, biomarker analysis and biospecimen storage.
“All teams use centralized resources, including a data coordinating center, central labs, and biomarkers, which help ensure consistency in how data are collected, analyzed, and compared across the competition,” Justice explained.
There is another variable that cannot simply be centralized away. Trials are being conducted internationally, meaning teams remain subject to different regulatory and ethical regimes; XPRIZE therefore has to create scientific commonality without pretending that the jurisdictions surrounding the studies are themselves uniform.
“While teams conduct their trials under the regulatory and ethics requirements of their local jurisdictions, all must also meet the competition’s standardized scientific and operational requirements,” said Justice. “This combination of centralized infrastructure and common outcome measures ensures that improvements in muscle, cognition, and immune function are evaluated as consistently and fairly as possible across every finalist.”
And then there is regulation
Standardizing evidence within a competition is one challenge; translating that evidence into a regulatory framework for healthspan therapeutics opens a considerably larger one.
XPRIZE does not set regulatory policy, and the finalist trials will operate according to local requirements for human-subject safety and monitoring. But Justice says the organization is engaging with the broader debate over how gerotherapeutics might eventually navigate regulatory pathways – including through recent discussions at the Reagan-Udall Foundation.
“That conversation explored frameworks while also addressing a critical gap: aging is the primary driver of many major chronic diseases, yet it remains largely absent from formal regulatory recognition as a therapeutic target,” she told us.
It is a familiar wrinkle for geroscience, but one that becomes increasingly difficult to treat as theoretical as interventions move into human testing. The question is not necessarily whether aging should simply be reclassified as a disease; it is how evidence that an intervention meaningfully improves several dimensions of age-related function might ultimately be translated into indications, endpoints and clinical adoption.
Justice is careful about where XPRIZE’s remit ends.
“While XPRIZE does not establish regulatory policy, the competition is designed to generate the kind of rigorous, standardized clinical evidence that regulators, researchers, and industry need to advance the field,” she said. “By demonstrating whether interventions can meaningfully improve muscle, cognitive, and immune function using common endpoints, the Finals aim to help lay the scientific foundation for future regulatory pathways and broader clinical adoption of healthspan-extending therapeutics.”
Evidence first, architecture later
That leaves XPRIZE in an interesting position. It cannot create a regulatory destination for gerotherapeutics, but it can attempt to make the evidence arriving at regulators’ doors considerably harder to dismiss – standardized, human and centered on function rather than theoretical rejuvenation.
For a field that has spent years debating how aging should be recognized, measured and treated, that distinction matters. First build the evidence; then see whether the architecture around it has to move.
