REPROGRAM: REsilience PROmotion with GeRoprotectors: AssessMent of biological effect. Rationale and protocol for a trial of biological effect.

The REPROGRAM trial is a randomized study designed to assess whether a three-week course of the geroprotectors Metformin, Fisetin, or Spermidin can reduce senescent cells and reverse other hallmarks of ageing in 60 healthy adults aged 70 and older.

The Gist

Imagine your body is like a high-performance car. When you're young, the engine runs smoothly, the tires grip the road perfectly, and if you hit a bump (like a cold, a fall, or surgery), the car bounces back quickly. This ability to bounce back is called resilience.

As we get older, the car starts to show wear and tear. The engine gets sluggish, the suspension gets stiff, and a small bump might leave the car shaking for days. Scientists call this "aging," and they've identified specific parts of the engine that are breaking down, like rusted gears or clogged filters. These are called the "Hallmarks of Aging."

The REPROGRAM trial is a new experiment trying to figure out if we can use special "mechanic's tools" (drugs) to fix these specific parts of the engine and make the car resilient again, even in older people.

The Three "Mechanic's Tools" (The Interventions)

The researchers are testing three different substances that have shown promise in fixing aging engines in mice and lab dishes. They are giving these to 60 healthy people over the age of 70. Think of the participants as three different garages, each trying a different tool:

1. Metformin (The Fuel Optimizer): This is a common diabetes drug. Imagine it as a tune-up for the car's fuel system. It helps the body use energy more efficiently and stops the engine from overheating (inflammation).
2. Fisetin (The Rust Remover): Found in strawberries and apples, this is like a specialized cleaner that targets "rusty" cells (senescent cells) that have stopped working but won't die, clogging up the engine. Fisetin helps clear them out.
3. Spermidine (The Self-Cleaning System): Found in foods like wheat germ and cheese, this acts like a self-cleaning cycle for the car. It helps the body recycle old, broken parts and replace them with fresh ones (a process called autophagy).

The Experiment: A "Surgical Window"

Usually, doctors give medicine for years to see if it works. But this trial is different. It's like a test drive.

• The Duration: The participants take one of these three tools for just three weeks.
• The Goal: They aren't waiting to see if the car lasts 10 more years. They want to see if, after just three weeks, the engine starts to run better.
• The Check-Up: Before the test drive, the researchers take a deep look at the engine. They take small samples of fat tissue (like checking the oil), blood, and even a stool sample (to check the exhaust system/microbiome). They do this again after the three weeks to see if the "rust" is gone, the "fuel" is burning cleaner, and the "self-cleaning" system is working.

Why Do This?

Right now, we know these tools work in mice, but we don't know exactly how they work in humans or which ones are best for which people.

• The Big Question: Can we actually reverse the "rust" and "wear and tear" in a human body in just a few weeks?
• The Future: If this works, doctors could use these tools as "pre-habilitation." Imagine before an older person has major surgery, they take one of these tools for a month to "tune up" their engine. This would help them recover faster and avoid complications, just like a well-tuned car handles a bumpy road better.

The Rules of the Road

• Who is driving? Healthy people over 70.
• Is there a placebo? No. Everyone gets one of the three real tools because the goal is to see how the biology changes, not just if they feel better.
• Safety First: The team is watching closely. If a tool causes a problem (like a check-engine light), they stop immediately.
• The Team: This is a big team effort involving doctors, scientists, and experts from universities in Birmingham and London, funded by a major health organization (Wellcome Leap).

The Bottom Line

The REPROGRAM trial is like a high-tech diagnostic session for the human body. It's trying to prove that aging isn't just an inevitable decline, but a mechanical process that can be tweaked and improved with the right tools. If they find the right combination, it could change how we help older adults stay strong, recover from illness, and live their best lives.

Technical Summary

Based on the provided preprint, here is a detailed technical summary of the REPROGRAM trial protocol.

1. Problem Statement

Ageing is characterized by a decline in physiological resilience, defined as the ability to maintain homeostasis when facing stressors such as infection, surgery, or falls. This reduced resilience is driven by the "hallmarks of ageing" (e.g., cellular senescence, mitochondrial dysfunction, chronic inflammation, and stem cell exhaustion).

While geroprotectors (drugs proposed to slow ageing and extend healthspan) have shown promise in animal models, there is a critical lack of robust pharmacodynamic and pharmacokinetic data in healthy older humans. Specifically:

• It is unclear if these agents can reverse specific biological pathways in vivo within a clinically relevant timeframe.
• There is insufficient evidence on which patient subgroups benefit most, hindering the development of stratified medicine approaches for ageing.
• Previous clinical trials have yielded conflicting or disappointing results regarding functional outcomes, necessitating a focus on deep biological phenotyping to understand mechanisms of action.

2. Methodology

The REPROGRAM trial is a Phase IIa, single-site, open-label, randomized controlled trial designed to mimic a "surgical window of opportunity" (a short-term intervention to assess biological impact).

• Study Population: 60 healthy volunteers (30 male, 30 female) aged ≥70 years.
• Intervention Arms: Participants are stratified by sex and randomized into three arms (n=20 per arm):
  1. Metformin MR: 1500mg once daily (after a 1-week titration from 500mg).
  2. Fisetin: 100mg once daily.
  3. Spermidine: 15mg once daily.
  • Duration: 3 weeks of treatment.
• Study Setting: University Hospitals Birmingham NHS Foundation Trust, UK.
• Data Collection Timeline:
  • Visit 1: Consent, clinical assessment, blood draw (baseline).
  • Visit 2 (1 week later): Adipose tissue biopsy, stool collection, randomization, intervention start.
  • Visit 3 (3 weeks post-intervention): Adipose tissue biopsy, stool collection, blood draw, adherence check.
• Primary Outcome: Change in the number of senescent cells in abdominal adipose tissue, measured by SA-β-GAL (Senescence-associated beta-galactosidase) staining, adjusted for baseline.
• Secondary & Exploratory Outcomes: A comprehensive multi-omics assessment including:
  • Senescence: Transcriptomics (SenMayo analysis) of adipose tissue.
  • Epigenetics: DNA methylation clocks (epigenetic age) in blood and adipose.
  • Immunology: Immune cell frequencies, immunosenescence features (IMM-AGE score), and mTOR signaling via spectral flow cytometry.
  • Metabolism: Autophagic flux, mitochondrial function (Seahorse respirometry), and nutrient sensing.
  • Inflammation: Cytokine profiling (ELISA/multiplex).
  • Stem Cells: Adipose-derived stem cell exhaustion.
  • Microbiome: Stool metagenomics.
  • Neurology: Neural oscillatory signatures via EEG.
• Statistical Analysis:
  • Primary analysis uses a Per-Protocol approach (paired t-tests/Wilcoxon signed-rank tests) for participants completing the intervention with paired samples.
  • Intention-to-Treat analysis will also be conducted.
  • Advanced machine learning (Canonical Correlation Analysis, LASSO, Elastic Net) will be used to identify baseline predictors of biological response and link findings to the concurrent REBOUND cohort study (cancer surgery patients).

3. Key Contributions

• Mechanistic Focus: Unlike many geroprotector trials that focus solely on clinical endpoints (e.g., gait speed, mortality), this trial prioritizes biological endpoints to determine if and how these drugs modify the hallmarks of ageing in humans.
• Multi-Modal Phenotyping: The study integrates deep clinical phenotyping (frailty, sarcopenia, cognitive assessment) with high-dimensional biological data (transcriptomics, metabolomics, epigenetics, microbiome).
• Stratified Medicine Framework: By correlating baseline biological markers with intervention responses, the study aims to identify biomarkers that predict who will respond to specific geroprotectors, paving the way for personalized anti-ageing therapies.
• Synergy with REBOUND: The trial is designed to complement the REBOUND cohort study, allowing researchers to test if biological pathways identified as drivers of impaired resilience in cancer patients can be ameliorated by geroprotectors in healthy older adults.
• Safety & Dosing Strategy: The protocol utilizes established, safe dosing regimens derived from previous literature and includes a titration period for Metformin to minimize adverse events.

4. Results

• Status: As this is a protocol paper (preprint), no results are yet available.
• Timeline: Recruitment began in September 2025, with data collection expected to conclude by July 2026 and results anticipated by October 2026.
• Sample Size Justification: The sample size (60 participants) is calculated to detect a 5% mean difference in SA-β-GAL with 80% power, based on data from previous senolytic trials.

5. Significance

The REPROGRAM trial addresses a critical gap in geroscience: the translation of animal model findings to human biology.

• Scientific Impact: If successful, it will provide the first robust evidence of whether short-term geroprotector administration can reverse specific hallmarks of ageing (particularly senescence) in healthy older humans.
• Clinical Translation: The findings will inform the design of future, larger-scale trials targeting frailty and resilience. It aims to move the field from "one-size-fits-all" interventions to precision geroscience, where treatments are targeted based on an individual's specific biological age and pathway vulnerabilities.
• Public Health: By identifying agents that improve resilience, the study could lead to prehabilitation strategies for older adults facing major stressors (like surgery), potentially reducing post-operative complications and improving healthspan.

Note: This document is a preprint (medRxiv) and has not yet undergone peer review. The trial is registered with ISRCTN (ISRCTN47919839) and funded by the Wellcome Leap Dynamic Resilience programme.