Semaglutide slows epigenetic aging in a randomized trial of HIV-associated lipohypertrophy

Glucagon-like peptide-1 (GLP-1) receptor agonists have attracted interest as gerotherapeutics, yet clinical-trial evidence for their effects on biological aging is lacking. We report a post hoc exploratory epigenetic age analysis of a 32-week, randomized, double-blind, placebo-controlled phase 2b trial (NCT04019197) of semaglutide in adults with human immunodeficiency virus (HIV)-associated lipohypertrophy (semaglutide n = 45; placebo n = 39). The parent trial's primary endpoint was change in visceral adipose tissue, with secondary cardiometabolic and body-composition endpoints; epigenetic aging was not pre-specified. To address this gap, we profiled peripheral-blood DNA methylation (DNAm) at baseline and week 32 to assess semaglutide versus placebo on first-, second-, and third-generation epigenetic aging measures. In adjusted analyses, semaglutide reduced epigenetic aging across multiple second- and third-generation clocks, including PhenoAge ( - 4.9 years/year, p = 0.004), PCGrimAge ( - 3.1, p = 0.007), GrimAge V2 ( - 2.3, p = 0.009), OMICmAge ( - 2.2, p = 0.009), RetroAge ( - 2.2, p = 0.030), and DunedinPACE ( - 0.09 units, 9% slower, p = 0.01). Systems-based clocks showed parallel reductions in inflammation, brain, and heart aging measures. The post hoc design, modest sample size, HIV-specific cohort, and 32-week follow-up limit generalizability. Prospective trials are needed to determine whether GLP-1 receptor agonists can be repurposed as gerotherapeutics.