Welcome to the Golden Era of Rejuvenation Science

Startups and academics are making notable progress in tackling the aging process. Will they succeed?

HSBC x Wired Consulting | Frontiers Biotech | AntiAging 2

Imagine a world where we can slow down, stall, or perhaps even reverse, our biological clocks. Where a 22-year-old can look and feel that way for longer and a 65-year-old can return their mind and body to that age once again. Scientists believe that this is no longer a preposterous suggestion.

Right now, we are in the midst of a golden age of longevity research. Huge sums have recently poured into this space, most conspicuously from Silicon Valley billionaires. Alongside traditional players such as pharmaceutical companies and research institutions, an array of headline-grabbing startups have emerged, and a notable anti-aging industry is coalescing. In 2022, an estimated $5.2bn was invested into 130 longevity companies; the market is forecast to be worth $44.2bn annually by 2030.

“Our understanding of aging has come of age,” says Professor Dame Linda Partridge, founding Director of the Max Planck Institute for Biology of Ageing in Cologne, and a Professorial Fellow at the UCL Institute of Healthy Ageing. “We can target its mechanisms to keep healthy as we get older, and it’s now one of the hottest topics in pharma.”

Among humanity’s great successes is the extension of human life. In 1900, the average life expectancy was 32 years, but now it’s more than 70. We’ve achieved this through technologies such as seat belts and life jackets, but also vaccines and medicines that enable us to avoid and treat infectious and chronic diseases.

But in doing so we’ve highlighted how much our bodies degrade over time. The symptoms of age include brittle bones and weak muscles, as well as the increased risk of diseases such as dementia and cancer.

“So what’s increasing—and it really is a problem—is a period of disability, ill health, outright disease, and multimorbidity in late life, and it’s something that we need to tackle,” says Partridge. “We need to squash that period of bad things happening at the end of life so people stay functional, healthy, and happy for longer.”

To this end, scientists have been investigating how to control aging, and specifically whether we can address not only its symptoms, but its causes. There was little hope until 1993, when scientists discovered that you can extend a worm’s lifespan by disabling a single gene. The worms appeared to be healthy until the end, meaning their aging had been slowed rather than their lives simply extended.

Out of this work came a realization of “how plastic, how malleable, the aging process is,” says Partridge. Its impact was to trigger a flurry of research into the cellular processes that cause aging in humans and various methods that could be used to tackle them.

“I think what has changed has been a real molecular, cellular, and mechanical understanding of the underlying processes that are affected by the things that we all know about, like diet and exercise,” says Partridge. “We might be able to manipulate them in other ways, with drugs or with cell technology.”

One discovery has been that the biological clock in cells can be turned back. By adding a cocktail of four proteins, typical human adult cells can be converted into youthful stem cells, which look and act like those in a newly formed embryo. In 2022, scientists used this approach to rewind the biological clock of human skin cells by around 30 years, according to molecular measures.

Still, we’re a long way off being able to use this on humans. According to Partridge, cellular rejuvenation might theoretically be useful for treating certain diseases, but before it can ever be used to wind back a human’s biological clock it must be shown not to be harmful. “The process needs to be very safe if a lot of people are going to undertake it,” she says. And that’s assuming the therapy can actually be administered in practice.

That’s why Partridge believes we may have more immediate success with another major strand of current longevity research: Identifying existing drugs that can also be used to target the causes of aging. New computational techniques that encompass molecular simulations, genomics, and machine learning are proving powerful in helping prioritize drug-repurposing candidates.

Take the cancer drug dasatinib, for instance, which when administered with quercetin, a molecule found in colorful fruit and vegetables, has been shown to stimulate apoptosis. This is the process whereby the body clears out “senescent” cells, which are cells that have stopped dividing. Senescent cells seem to promote the onset of age-related diseases and there’s evidence that removing them can slow the aging process. Of the current wave of anti-aging startups, many of those that are not focused on cellular reprogramming are looking at developing treatments that target senescent cells.

Or consider rapamycin, an immunosuppressant drug that has demonstrated a secondary ability to increase life expectancy. The drug targets the body’s nutrient-sensing systems, causing them to believe it is in starvation mode and activating the life-extending processes that help humans survive on few calories.

“Drug repurposing is a real opportunity at the moment, and there is a lot of work going on,” Partridge says. “Existing drugs that target things that we know go wrong during aging can often be used at much lower doses with benefits to health.”

But we need to know more about how these drugs affect humans, and that’s challenging. It would require enlisting a lot of people to take low doses of rapamycin, say, for a long period—and then tracking multiple outputs because there are so many things that can go wrong during aging. This process would be extremely expensive.

If truly effective anti-aging treatments emerge, they are going to face numerous ethical and social questions. One common concern is that unless we can ensure they’re made available to all, they will accentuate the wealth divide.

Yet if we do make them widely available, they will accelerate population growth to the detriment of the global ecosystem. Some therefore feel they shouldn’t be available to anyone.

For now, that's a conundrum for down the road. “What the science of aging is telling us is that if you target mechanisms of aging, then you can target multiple things that go wrong with aging simultaneously,” she says. “We may know that in principle, but now it’s about proving it in practice.”