Semaglutide Slows Epigenetic Aging in First Randomized Trial, Nature Communications Study of HIV Patients Finds
A UC San Diego-led trial found semaglutide significantly slowed multiple epigenetic aging clocks over 32 weeks in adults with HIV-associated lipohypertrophy, per a Nature Communications study.
Editor's Note ·
- Correction:
- The article quotes Michael Corley as saying, "the key point is that this is the first randomized, placebo-controlled clinical evidence that a GLP-1 receptor agonist may slow the biological processes associated with aging in humans," and attributes this to Technology Networks. Corley made this statement to Medical News Today, not to Technology Networks. The quote is accurate; the source attribution was wrong.
Overview
Semaglutide, the GLP-1 receptor agonist sold as Ozempic and Wegovy, slowed several molecular markers of biological aging in a 32-week randomized, placebo-controlled trial of adults with HIV-associated lipohypertrophy, according to a study published in Nature Communications on May 19, 2026. The paper’s authors describe the analysis as the first clinical-trial evidence that semaglutide modulates validated epigenetic biomarkers of aging, a result the research team is treating as an early signal rather than proof the drug extends life.
The work was led by Michael Corley, PhD, associate professor at UC San Diego School of Medicine and the Stein Institute for Research on Aging, alongside co-authors from TruDiagnostic, Weill Cornell Medicine, University Hospitals Cleveland Medical Center, Case Western Reserve University, and the Medical University of South Carolina, according to the study’s listing on PubMed Central.
What We Know
The underlying trial originally enrolled 108 adults with HIV-associated lipohypertrophy — abnormal fat accumulation that can occur in people living with HIV — and randomized them to weekly semaglutide injections or placebo, according to UC San Diego Today. Researchers later ran a post hoc analysis on paired blood samples from 84 of those participants — 45 who received semaglutide and 39 who received placebo — comparing DNA methylation patterns at the start of the trial and again after 32 weeks, according to Nature Communications.
After adjusting for sex, body mass index, and inflammation markers, the semaglutide group showed significant slowing across several epigenetic clocks — tools that estimate biological age from DNA methylation patterns — compared with placebo. PhenoAge dropped by 4.9 years per year of follow-up (p = 0.004), PCGrimAge by 3.1 years (p = 0.007), and GrimAge V2 by 2.3 years (p = 0.009), while the DunedinPACE clock, which measures the pace of aging rather than a fixed age, slowed by about 9 percent (p = 0.01), according to Nature Communications. Two additional measures, the multi-omic OMICmAge clock and the transposable-element-focused RetroAge clock, also showed significant decreases, while a separate Intrinsic Capacity clock designed to capture resilience showed no significant change, according to the PubMed Central-hosted version of the study.
Corley said the results should be read cautiously. “We are not saying that semaglutide reverses aging or makes people younger. What we are seeing is a signal that it may slow some of the biological processes associated with aging,” he said, according to UC San Diego Today. He added that “many of the biological processes we study in HIV are also central to aging in the general population,” according to the same release.
Corley told Technology Networks that “the key point is that this is the first randomized, placebo-controlled clinical evidence that a GLP-1 receptor agonist may slow the biological processes associated with aging in humans.”
Corley also described the HIV-associated lipohypertrophy population studied in the trial. “Biologically, that population appears to be, on average, around five years older,” he told KPBS. Participants on semaglutide, he said, “were living 32 weeks in a condition that was more optimal for their body, in terms of some of these biomarkers of aging.”
What We Don’t Know
The study’s authors caution that the analysis was a post hoc exploratory look at existing samples rather than a trial originally designed to test aging outcomes, and that its “post hoc design, modest sample size, HIV-specific cohort, and 32-week follow-up limit generalizability,” according to Nature Communications. Whether similar effects would appear in people without HIV, or in those without obesity or diabetes diagnoses, remains untested, according to KPBS.
It is also unclear whether the epigenetic changes persist after treatment stops. “The question is, if they went off those medications, would that snap back?” Corley said, according to KPBS. None of the epigenetic clock changes reported in the trial have yet been linked to measurable clinical outcomes such as disease incidence or lifespan, and the research team says larger, longer trials are needed before the findings could inform how semaglutide is prescribed or discussed as a potential gerotherapeutic.