Partial Epigenetic Reprogramming as a Strategy for Biological Aging Reversal: Preclinical Evidence, Mechanistic Framework, and the Transition to First-in-Human Clinical Trials

Biological aging has long been regarded as an immutable hallmark of living systems. However, recent breakthroughs in epigenetic science are fundamentally challenging this assumption. This review examines the theoretical foundations and experimental evidence supporting partial epigenetic reprogramming as a viable strategy to reverse cellular aging phenotypes while preserving cell identity. Central to this emerging framework is David Sinclair’s Information Theory of Aging, which proposes that the gradual degradation of epigenetic information—rather than the mere accumulation of genomic mutations—is the primary driver of organismal aging. Preclinical studies employing subsets of Shinya Yamanaka factors (OCT4, SOX2, KLF4; collectively referred to as OSK) have demonstrated remarkable outcomes, including: Restoration of youthful gene expression profiles, Reversal of epigenetic clock measurements by up to 75% of accumulated biological age markers, and Functional rejuvenation such as vision recovery, enhanced wound healing, and restored metabolic parameters in both murine and non-human primate models. Building upon this foundational work, Life Biosciences received U.S. Food and Drug Administration Investigational New Drug (IND) clearance in January 2026 for ER-100, the first gene therapy based on partial epigenetic reprogramming to advance into human clinical trials. The Phase 1 study targets open-angle glaucoma and non-arteritic anterior ischemic optic neuropathy (NAION), with primary endpoints emphasizing safety and tolerability. This review situates these developments within the broader landscape of longevity research, addresses the methodological limitations and ethical implications inherent to reprogramming-based interventions, and outlines prospective trajectories for the evolving field of age reversal biotechnology.