Researchers have published the first human evidence that a class of antiretroviral drugs, already approved by the U.S. Food and Drug Administration for HIV treatment, can measurably reduce biological age in healthy adults. The findings, reported in an open-access study, represent a significant step toward repurposing existing medicines as anti-aging therapies.

The study focused on retrotransposons, ancient viral remnants embedded in human DNA that account for nearly half the genome. In youth, these sequences remain dormant, suppressed by epigenetic controls. With age, those controls erode, allowing retrotransposons to reactivate. The resulting molecular activity mimics a viral infection, triggering chronic inflammation and contributing to tissue degeneration, hallmarks of biological aging.

Investigators evaluated two FDA-approved nucleoside reverse transcriptase inhibitor (NRTI) regimens in healthy volunteers aged 18 to 50, administered over 12 weeks. Participants taking a combination of emtricitabine and tenofovir alafenamide (FTC/TAF) showed significant reductions across multiple DNA methylation-based aging clocks, including a 6.33-year decrease in PhenoAge and a meaningful drop in DunedinPACE, a measure of the rate of biological aging. Epigenetic markers of inflammation, including IL-6 and C-reactive protein proxies, also declined. A second regimen, emtricitabine combined with tenofovir disoproxil fumarate (FTC/TDF), produced no significant changes in the same measures.

The divergence between the two drug combinations points to the importance of cellular pharmacology in determining anti-aging efficacy. TAF, the newer formulation, is known to achieve higher intracellular concentrations at lower doses, which researchers suggest may account for its superior effect on epigenetic aging measures.

The authors call for prospective, placebo-controlled trials to validate the findings and to directly measure transposable element activity alongside clinical and epigenetic endpoints. If confirmed, NRTI-based therapies could represent a new class of gerotherapeutics; medicines targeting the mechanisms of aging itself rather than individual diseases.