David Sinclair plans oral SL-100 trials in XPrize’s $101M age-reversal contest

David Sinclair is taking his age-reversal pitch from social media and animal labs into human trials, and he’s doing it inside a money-on-the-table competition. MIT Technology Review reports that Sinclair plans to use an oral “reprogramming” drug mixture, code-named SL-100, with volunteers as part of XPrize Foundation’s $101 million Healthspan Competition. The competition is structured around proving “restoration” to an earlier apparent age, judged through improvements in immune, cognitive, and muscle function. The grand prize goes to any team able to demonstrate a 10-year (or greater) relative improvement after one year of treatment.

Sinclair, reached by phone, confirmed he plans to give an oral agent to seek “evidence for age restoration in humans.” Importantly, the stakes are not vague. XPrize is not paying for vibes; it is paying for measurable changes over a defined timeframe, and it is trying to force the field to answer a question that regulators, scientists, and payers all wrestle with: if a medicine changes how people age, what evidence actually counts. Sinclair’s stated goal is whole-body effect, not a single organ. He frames the approach as “epigenetically restore the animal and eventually the person,” and he says his lab is doing extensive animal studies with the oral agent and is preparing to compete.

That matters because reprogramming has been heating up from multiple angles, and different approaches imply different risk profiles. Sinclair’s strategy is “chemical reprogramming,” which uses drugs to mimic the effects of embryonic genes discovered about 20 years ago, when researchers found powerful genes can turn adult cells into stem cell-like cells. The assumed biology involves resetting molecular controls on DNA, called epigenetic marks, which help determine a cell’s overall metabolism and identity. In theory, if you can shift those marks across the body, you can move beyond symptom treatment toward rejuvenation.

Other players are trying, and they may shape investor expectations about speed and feasibility. Sinclair’s own company, Life Biosciences, recently made news by winning approval to launch an initial human trial using a set of powerful reprogramming genes. That test is a complex gene therapy and is limited to patients’ eyes, where it could treat conditions like glaucoma. Sinclair’s XPrize plan is bolder because it targets what he suggests is the more practical route for systemic outcomes: swallow a chemical agent that travels through the bloodstream to reach most or all cells.

Still, the scientific and safety debate around chemical reprogramming is not theoretical. Some experts expressed caution, saying the chemical process used in labs is extremely harsh and not even particularly effective. Sergiy Velychko, founder of Soxogen, said chemicals are used in very high concentrations for cell reprogramming. This is the tradeoff teams bet on: if you can find the right dose, formulation, and sequence of compounds, you may get a body-wide effect. If you cannot, you risk toxicity without meaningful reversal.

Sinclair declined to describe the exact makeup of SL-100, calling its contents “highly, highly confidential.” But he has previously published lab studies of “epigenetic age-reversal cocktails” that mixed powerful chemicals with known supplements and commercially available medicines. In that earlier patent filing, he described ingredients including the supplement forskolin, the antidepressant tranylcypromine, and an experimental chemical, laduviglusib. The key operational advantage here is that using existing drugs and supplements potentially makes components easier to translate into human testing, since doctors can prescribe many approved medicines for unusual objectives.

Sinclair’s XPrize team is not the only one building a bridge from reprogramming concept to clinical trial mechanics. James Clement, head of Betterhumans, said he is “running clinical trials” of an oral reprogramming cocktail for Sinclair’s XPrize team. Meanwhile, the competition’s organizer is attempting to solve a measurement problem that has stalled progress across anti-aging medicine. Jamie Justice, a doctor and executive director for the contest, says the judging panel is picking 10 finalists from 65 teams exploring health foods, lifestyle interventions, digital trackers, and drug compounds. Sinclair’s team was a late entrant, but Justice said that like all teams it would be required to move into wider human tests starting this year, and it would still have to reach a winning bar that is “incredibly hard to even get to one winner,” since if two teams are equivalent they split the award. The contest is bankrolled by Saudi Arabia’s Hevolution Foundation, and it is led by executive chairman Peter Diamandis, an active promoter of longevity research.

This isn’t happening in isolation. The race to harness reprogramming is also speeding outside XPrize. On June 2, NewLimit, founded by crypto billionaire Brian Armstrong, said it raised an additional $435 million from investors including Peter Thiel’s Founders Fund to support “age reprogramming.” NewLimit says it is working toward delivering genetic reprogramming instructions to the liver to treat diseases of that organ. That’s a different modality, but the market implication is the same: capital is flowing toward rejuvenation, and teams that can produce credible outcome data will set the direction for what gets funded next.

Second-order, board-level consequence: the field’s credibility depends on measurement and safety, not just biology. Sinclair has been criticized by other scientists for unproven rejuvenation claims, including his past resignation as president of the Academy for Health and Lifespan Research after claiming a supplement developed by a company his brother runs had “reversed” the age of dogs, a claim that drew enough skepticism that one scientist called it a “lie.” Part of the challenge is that scientists still disagree on how to measure aging, and they also lack a reliable age-reversal measurement framework. Justice’s point is that standardized measures of aging are a central purpose of the competition. If XPrize can force agreement on what counts as meaningful improvement for immune, cognitive, and muscle function, and then tie that to long-term, regulator-friendly evidence standards, it could change how future rejuvenation products move through clinical development.

For executives and investors watching this space, the strategic stake is straightforward: Sinclair’s SL-100 plan is a high-visibility bet that oral chemical reprogramming can be made safe enough, measurable enough, and durable enough to clear a one-year bar tied to relative “10-year” improvement. Even if the science remains contested, the competition format pressures teams to produce data quickly and in a standardized way, which could reshape the timeline for when rejuvenation claims stop being marketing and start being evidence.