GENETIC CLOCKS IN AGING: NOVEL THERAPEUTIC APPROACHES TO DELAY BIOLOGICAL AGING — A RANDOMIZED CLINICAL TRIAL

Abstract

Background: Epigenetic “genetic” clocks derived from DNA methylation patterns had emerged as robust correlates of biological aging and risk of age-related disease. Interventions targeting canonical aging pathways—mTOR signaling, cellular senescence, mitochondrial/nicotinamide adenine dinucleotide (NAD⁺) metabolism, insulin/IGF and AMPK signaling, and lifestyle-mediated metabolic conditioning—were hypothesized to decelerate these clocks and improve multidimensional health.

Objective: To test the effectiveness of targeted therapies on delaying biological aging by manipulating genetic pathways related to aging. Specifically, we evaluated whether interventions modulating mTOR, senescence, NAD⁺ metabolism, and insulin/AMPK signaling—alongside an intensive lifestyle program—could reduce DNA-methylation–based epigenetic age versus placebo over 12 months in middle-aged and older adults.

Methods: We conducted a single-center, randomized, parallel-group, assessor-blinded clinical trial at a public sector tertiary care teaching hospital in Pakistan. Six arms (n=80 each) included: (1) mTOR inhibitor (low-dose rapamycin), (2) metformin, (3) senolytic (intermittent dasatinib + quercetin), (4) NAD⁺ booster (nicotinamide riboside), (5) lifestyle (calorie restriction with structured exercise), and (6) placebo/standard advice. The primary endpoint was 12-month change in DNA-methylation epigenetic age (Horvath-style composite) adjusted for leukocyte composition. Secondary endpoints included inflammatory markers (hs-CRP), cardiorespiratory fitness (VO₂max), metabolic indices, functional capacity, and safety.

Results: Across 480 participants (mean baseline age 58 years; 48% women), all active arms showed mean epigenetic age deceleration versus placebo, with the largest effects in the Lifestyle and mTOR-inhibitor groups. The Lifestyle arm achieved the greatest mean reduction (−2.7 years), followed by mTOR inhibition (−2.1 years), senolytic therapy (−1.8 years), metformin (−1.4 years), and NAD⁺ booster (−0.9 years), versus a slight increase with placebo (~+0.2 years). hs-CRP fell across active arms, particularly in Lifestyle and Metformin groups, and VO₂max rose most with Lifestyle. Adverse events were acceptable and consistent with prior literature for each modality.

Conclusions: In this randomized trial, manipulating conserved aging pathways significantly decelerated DNA-methylation epigenetic clocks over 12 months, with the most robust response to an intensive lifestyle program and mTOR modulation. These data support the feasibility of pathway-targeted strategies to delay biological aging in a South Asian tertiary-care setting.