Therapeutic reversal of cellular senescence: A systematic review of senolytics, senomorphics and anti-ageing therapies in human clinical trials.

Cellular senescence, a key feature of ageing, involves irreversible cell cycle arrest and the secretion of pro-inflammatory senescence-associated secretory phenotype (SASP) factors, which contribute to tissue degeneration and age-related diseases. Targeting senescent cells with senolytics, senomorphics and anti-ageing therapies marks a major shift in translational geroscience, with the potential to delay or reverse age-related conditions. A systematic review and narrative synthesis was conducted in accordance with PRISMA 2020 guidelines. Eligible human clinical studies evaluating pharmacological interventions targeting cellular senescence were included, comprising randomized and nonrandomized clinical trials and pilot studies reporting clinical, functional or senescence-associated outcomes. Data on study characteristics, interventions, efficacy, safety and senescence-associated biomarkers were extracted and synthesized qualitatively. Six completed clinical studies were included in the evidence synthesis, with one additional ongoing clinical trial identified separately. Senolytic interventions, particularly dasatinib plus quercetin, showed preliminary improvements in selected functional outcomes and reductions in senescence-associated biomarkers, while senomorphic and mTOR-targeting interventions demonstrated effects on selected tissue and immune-related outcomes. Reported adverse events were generally mild or manageable, but small sample sizes and short follow-up limited assessment of uncommon and long-term safety risks. Current evidence suggests that pharmacological targeting of cellular senescence is feasible and may produce measurable biological and functional effects in humans, but evidence remains insufficient to establish clinical efficacy or long-term safety. Senolytic and senomorphic strategies should therefore be considered investigational rather than established therapies. Larger, adequately powered randomized trials with standardized senescence biomarkers, clinically meaningful outcomes, longer follow-up and systematic safety assessment are needed.