Yuancheng (Ryan) Lu, 34, a geneticist at the Whitehead Institute in Cambridge, Massachusetts, has developed an age-reversal technique called reprogramming to repair optic nerves. In 2018, while earning his Ph. D. at Harvard Medical School, he used this method to restore vision in blind mice by injecting their cells with a gene therapy that returned them to a youthful state.

Sixteen days later, the nerves were regrowing. This year, the treatment, now called ER-100, entered human clinical trials. On June 9, the startup Life Biosciences announced it had injected the therapy into a person with glaucoma.

Lu trimmed the reprogramming genes to just OSK, removing Myc to avoid cancer risks, and chose the eye for its accessibility. His 2020 Nature publication sparked an investment rush, with US tech billionaires backing companies like Altos Labs and New Limit. Lu's collaborator, longevity scientist David Sinclair, recalls seeing the first nerve-regrowth images and declaring, "I see the future." Despite the hype, Lu remains focused on lab work, searching for "the next generation of rejuvenation therapies" while the treatment's toxicity to many cell types remains a challenge.