The era of the "100-year life" has effectively arrived, but staying healthy into old age remains an unsolved challenge. While average human lifespans have risen, age-related diseases such as dementia, sarcopenia, vision loss, osteoporosis, and cardiovascular disease place enormous burdens on individual lives and national finances alike. This is why rapidly aging countries around the world are asking whether aging itself can be treated. Earlier research focused on slowing individual diseases one by one, but recent global interest has moved a step further — toward the possibility of so-called "reverse aging," restoring already aged cells and tissues to a younger state.
Reverse-aging research began with the "Yamanaka factors." Professor Shinya Yamanaka of Kyoto University won the 2012 Nobel Prize in Physiology or Medicine for showing that "adult cells" with fixed roles in the body could be returned to a state similar to early-stage "embryonic stem cells" by introducing specific genes. He demonstrated that even cells with designated functions, such as skin cells, could be turned into induced pluripotent stem cells capable of differentiating into multiple tissues again when injected with particular genes. The key gene combination used is known as the "Yamanaka factors."
But fully rewinding a cell's clock proved difficult to translate directly into therapy. Once a cell loses its original identity and reverts to a stem-cell state, the risk of unexpected proliferation or tumor formation rises. Animal experiments have raised concerns that excessive activation of the Yamanaka factors can disrupt tissue structure and cause organ dysfunction.
The scientific community has since shifted its attention to "partial reprogramming," which rewinds cells only partway rather than all the way back to stem cells. Partial reprogramming activates the Yamanaka factors for only a short time or within a limited scope, reversing age-related changes without stripping cells of their original function. For example, rather than turning skin cells back into embryonic stem cells, the aim is to keep them as skin cells while making them behave like younger, more resilient ones.
The first field to approach the clinical threshold is the eye. In January, U.S. biotech firm Life Biosciences received Investigational New Drug clearance from the U.S. Food and Drug Administration for "ER-100," a partial epigenetic reprogramming therapy targeting optic nerve diseases. The Phase 1 trial will assess safety, tolerability, and potential improvements in visual function in patients with glaucoma and non-arteritic anterior ischemic optic neuropathy. Last month, the company secured an $80 million Series D round, accelerating both the ER-100 trial and the development of follow-on candidates. Reverse-aging technology is moving beyond the laboratory into a competitive race to develop human therapeutics.
The brain is another key target of reverse-aging research. Cognitive decline disorders such as Alzheimer's disease represent one of the heaviest burdens of an aging society. Once damaged, brain cells are hard to restore, and aging neurons lead to declines in memory, motor function, and emotional regulation. Researchers now view brain aging as involving not simply a reduction in cell numbers but also changes in gene expression and epigenetic regulation. A team led by Professor Johannes Gräff at the Brain Mind Institute of Switzerland's École Polytechnique Fédérale de Lausanne (EPFL) published a study this year in the journal Neuron applying partial reprogramming to "engram cells," the neuronal populations that store memory. The team used a gene therapy strategy to activate three Yamanaka factors — OCT4, SOX2, and KLF4 — in a brief and controlled manner. In aged mice and Alzheimer's model mice, some aging- and disease-related cellular features were alleviated, and learning and memory improved. The findings have raised hopes that technology capable of restoring youthful gene expression patterns while preserving cell identity could become a new approach to treating neurodegenerative diseases.
Skin is a field where reverse-aging research could gain broad public traction. Skin aging manifests visibly as wrinkles, loss of elasticity, and slower wound healing. A notable example is a 2022 study published in the journal eLife by researchers Diljeet Gill and Wolf Reik of the UK's Babraham Institute. The team exposed human skin fibroblasts obtained from middle-aged donors to Yamanaka factors for only about 13 days. The result: the cells retained their original function while their epigenetic age was rolled back by roughly 30 years. Skin reverse-aging research is not merely cosmetic technology; it has strong potential to expand into regenerative medicine aimed at restoring the recovery capacity of tissues weakened by aging.
Global companies are moving quickly. Altos Labs, launched in 2022 with the goals of cellular rejuvenation and disease recovery, has secured roughly $3 billion in initial funding. The backing reportedly includes participation from world-class researchers such as Professor Yamanaka and Juan Carlos Izpisúa Belmonte. Rather than defining aging itself as a single disease, Altos Labs is focused on restoring the recovery capacity of cells and tissues weakened by aging to address a range of age-related conditions.
In South Korea, efforts to broaden the foundation for reverse-aging research are also underway. The Korea Research Institute of Bioscience and Biotechnology (KRIBB) established an Aging Research Institute last year and is ramping up work on aging diagnostics, biological clocks, and reverse-aging therapeutics. Oh Doo-byung, head of KRIBB's Aging Research Institute, said, "Aging research isn't simply about extending lifespan — it's about enhancing resilience in later life and increasing the time people live in good health." He added, "We need full-cycle aging research that connects basic studies at the cellular level all the way through to clinical studies in humans."
