Here’s what you’ll learn when you read this story:

• Modern glaucoma treatments can only preserve a patient’s current level of vision, offering no hope of restoration.
• A new Phase 1 clinical trial is using gene therapy that could turn back the clock on aging cells and, possibly, regenerate the optic nerve.
• The world-first trial also comes with dangers—especially the possibility of the proliferation of cancerous cells.

As we age, so do our cells. But some scientists are wondering if we actually need to accept this inevitable entropy.

On June 9, Life Biosciences—a Boston-based biotech startup—conducted the world’s first gene therapy designed to treat optic neuropathies (damage/disease to the optic nerve that transmits all visual data to the brain) on a living patient. The treatment specifically targets open-angle glaucoma (OAG), the most common form of the disease, which clogs the drainage system of the eye and damages the optic nerve.

This Phase 1 clinical trial of the drug, which is known as ER-100, targets three genes—OCT4, SOX2 and KLF4 (OSK)—that are known to reprogram adult cells into more stem-like cell states. As Nature notes, previous animal studies have shown partial success, but such a technology is fraught with danger. Specifically, the treatment brings with it the possibility of the proliferation of cancerous cells. But while the eye is an immensely important organ, it’s not critical to staying alive, which makes it a good target for the first-ever treatment.

“Our research has suggested that aging is driven in large part by the loss of epigenetic information, not irreversible damage,” David Sinclair, a professor of genetics at Harvard Medical School and co-founder of Life Biosciences, said in a press statement. “This clinical study represents the first opportunity to test whether restoring that information can ameliorate human disease.”

Back in December of 2020, Sinclair and his team published findings in the journal Nature showing that it was possible to reprogram some cells in mice. The work built on a method that was previously explored in 2016 at the Salk Institute for Biological Studies in California, which identified a means to slow the cellular age of mice by manipulating these genes. But the treatments came with a major downside: If the genes were expressed in extra copies, or if they were expressed for too long, the mice could develop tumors.

In that 2020 study, Sinclair worked to develop a safer method by removing one of the genes associated with tumor growth and using a virus to ferry the desired genes to the target cells directly. The stated goal at the end of the study was to one day introduce the therapy to humans, though experts at the time noted that the treatment would likely need considerable refinement to be deemed truly safe.

Now, the world is about to find out if those refinements worked.

“Our preclinical studies have demonstrated that controlled OSK expression can reset epigenetic patterns associated with healthy cellular function, improve tissue performance, and restore visual function in animal models,” Sharon Rosenzweig‑Lipson, chief scientific officer at Life Biosciences, said in a press statement. “Advancing ER‑100 into the clinic is an important step toward translating epigenetic restoration into a new class of medicines for age-related diseases.”

Today’s modern glaucoma treatments can’t restore—or even improve—vision for the millions of adults struggling with the disease. But if scientists can find a way to turn back the cellular clock, that may no longer be the case.