Longevity Startups Have a Conundrum: Can They Sell Longevity Drugs?

In many ways, these are the best of times for Silicon Valley’s buzziest crop of longevity startups and their pursuit of drugs that can reverse aging.

NewLimit, a cell reprogramming company co-founded in 2022 by Coinbase CEO Brian Armstrong, announced earlier this month that it had raised another $435 million and plans to start testing a drug in humans next year. In all, it has collected over $630 million in funding.

Retro Biosciences, a startup launched in 2022 with $180 million from OpenAI’s Sam Altman, announced last month it too has raised more money and now has a $1.8 billion valuation. Retro, which is trying to restore cells and their activities that decline with aging, started testing its first drug in people last year.

Life Biosciences, a cell reprogramming company founded in 2017 whose investors include Joe Lonsdale’s 8VC, raised $80 million earlier this year, enough to complete the early phase of a clinical trial for its first drug. The company said this week it has dosed its first patient.

And yet despite these milestones, when I asked the CEOs of these companies if they are running trials for longevity drugs, each of them responded: Not yet.

In reality, these longevity startups face a delicate balancing act when talking about longevity drugs. On the one hand, investors and future customers are enticed by the idea that a drug might one day restore all the cells in their body to their former youthful glory. And yet, there’s also no getting around the stigma still attached to the word “longevity,” which is often accompanied by talk of living to 150 and has attracted influencers selling an array of unproven but supposedly life-extending products.

Even more challenging, the Food and Drug Administration does not consider aging a disease. So these startups are in a delicate position: They need revenue to fund their quests to develop anti-aging treatments, but for the time being, they have to pitch the potential value of their earliest drugs in more straightforward terms, describing how they treat specific diseases, not aging itself.

The first patient that was dosed in the Life Biosciences trial this week has glaucoma, an eye condition that is more common as people age and that can lead to vision loss. “We believe this is the most expedient and most efficient way to bring our products to market,” said Jerry McLaughlin, the company’s CEO.

Retro Biosciences is developing a drug intended to restore aging cells’ ability to clear out toxic proteins that accumulate and can cause cognitive decline. The company, which has so far enrolled healthy volunteers in the trial, intends to treat Alzheimer’s disease. To commercialize the drug, the company just has to prove it makes a difference in a disease whose risks increase during aging, not that it stymies aging itself.

“It’s a lot harder to measure the outcome of drugs that slow aging,” said Joe Betts-LaCroix, CEO and co-founder of Retro.

NewLimit, for its part, hopes to start testing its drug in people with fatty liver disease first, followed by patients with more severe alcohol-associated liver disease. As people get older, proteins that are supposed to only be found inside liver cells start to leak into the bloodstream. If NewLimit can show the drug is safe and effective, the population of people eligible to use it is likely to expand and eventually might include “everyone over 60,” said Jacob Kimmel, NewLimit’s president and co-founder.

Even though NewLimit’s premise is that its drug is making old cells younger, Kimmel said he is hesitant to describe what the company is doing as “reversing aging,” long considered a holy grail among the Silicon Valley tech elite.

“The framing I like better is that we’re restoring youthful function,” Kimmel said. “We’re not trying to make—atom for atom—the old cell exactly like the young one. We’re trying to fix the parts that are really critical.”

After talking to the CEOs, it struck me that the biggest challenge to truly developing longevity drugs remains unsolved: how to measure whether a drug is extending someone’s lifespan without having to wait 40 years to prove it works.

Regulators, academics and entrepreneurs are working on the problem. Last month, the Reagan-Udall Foundation for the FDA hosted a conference focused on accelerating the development of gerotherapeutics, a fancy name for longevity drugs. There, an official from the Advanced Research Projects Agency for Health—a federal agency created in 2022 to fund high-risk research—spoke about a $144 million effort that will include developing and testing new ways to measure if a drug is slowing down aging.

“Nobody has defined yet what the bar for success is in a longevity trial,” said Martin Borch Jensen, co-founder and chief scientific officer of Gordian Biotechnology.

Jensen told me he considers Gordian “a longevity company.” Still, Gordian’s first drug under development is to treat osteoarthritis, not aging, Jensen said.

Finding a way to accurately predict someone’s longevity is also on the mind of Kristen Fortney, CEO and co-founder of BioAge Labs. BioAge recently announced it had completed an early human trial for a drug that blocks the inflammation-causing protein NLRP3 in people who are obese and at high risk for cardiovascular disease.

Fortney said NLRP3 protein levels also rise in healthy people as they age. Recent research by BioAge and other companies indicates that people who are otherwise healthy but have higher amounts of NLRP3 at middle age don’t live as long as people in the same age group with lower amounts. To me, the protein sounded like a promising future candidate to predict longevity.

Maybe so, but for now at least, longevity trials remain confounding. “We are still figuring it out as a field,” Fortney said.