Alzheimer's Prevention: Viagra and Shingles Vaccine Show Promise in University of Exeter Study

University of Exeter Leads Charge in Alzheimer's Drug Repurposing Research

A groundbreaking study from the University of Exeter has pinpointed three everyday medications with surprising potential to combat Alzheimer's disease, spotlighting the shingles vaccine Zostavax as the top candidate. Published in Alzheimer's Research & Therapy on November 18, 2025, this research represents a pivotal moment in drug repurposing efforts. Led by Professor Clive Ballard and Dr. Anne Corbett from the College of Medicine and Health, the work harnesses an international panel of dementia experts to evaluate 80 existing drugs, fast-tracking solutions for a condition affecting nearly one million people in the UK.

Alzheimer's disease, the most common form of dementia characterized by progressive memory loss, cognitive decline, and neuron damage due to amyloid-beta plaques and tau tangles, remains the UK's leading cause of death. With projections estimating 1.4 million cases by 2040, the urgency for accessible preventives cannot be overstated. This University of Exeter-led initiative underscores higher education's role in translating lab insights into real-world health gains, offering hope through familiar treatments already proven safe.

The Delphi Consensus Method: Rigorous Science Behind the Selections

The study's methodology, a Delphi consensus process, involved 21 to 23 global experts from academia, clinics, and pharma iteratively ranking candidates anonymously. Drugs were assessed on biological relevance to Alzheimer's pathology—like inflammation, vascular issues, and protein aggregation—preclinical efficacy from cell and animal models, human observational data, and safety for older adults.

Starting with 80 nominations, systematic reviews narrowed to eight shortlists, with consensus requiring median scores and statistical separation. A lay advisory group of caregivers provided patient-centered input, prioritizing ease of use. This structured approach ensures robust, unbiased prioritization, exemplifying advanced research methodologies at institutions like the University of Exeter.

Shingles Vaccine Zostavax Tops List for Alzheimer's Prevention

Zostavax, the live attenuated herpes zoster vaccine administered in up to two doses, emerged as the most promising repurposed agent. Herpes zoster (shingles), caused by varicella-zoster virus reactivation, links to neuroinflammation potentially accelerating dementia. Vaccination modulates immunity, boosting antiviral cytokines and curbing pathogen-driven brain changes.

Epidemiological evidence is compelling: Studies across UK, Canada, and Australia involving nearly 941,000 participants show 16-20% reduced dementia risk post-vaccination. A Welsh natural experiment reported 20% fewer new diagnoses, while recombinant versions like Shingrix show 17% lower onset. Safe with mild side effects like injection-site pain, Zostavax suits widespread use. University of Exeter plans a large UK trial via the PROTECT platform, tracking thousands longitudinally for brain health markers.

• Reduces shingles reactivation risk by over 50% in older adults.
• Population-level data supports preventive potential independent of virus.
• Cost-effective: Free on NHS for eligible over-70s.

Dr. Anne Corbett notes, "Drug repurposing turns today's medicines into tomorrow's dementia shields," highlighting accelerated timelines versus de novo development.

Sildenafil (Viagra): Boosting Brain Blood Flow Against Alzheimer's

Sildenafil, a phosphodiesterase-5 (PDE5) inhibitor best known as Viagra for erectile dysfunction, ranked second. It enhances cyclic GMP levels, dilating blood vessels to improve cerebral perfusion—crucial as vascular dysfunction contributes to 20-40% of dementia cases.

Preclinical studies in AD mouse models (APP/PS1, Tg2576) demonstrate neurite outgrowth, tau dephosphorylation, amyloid-beta reduction, and cognitive rescue. Human data: Cleveland Clinic analysis of millions found 50% lower Alzheimer's risk; Oxford trials confirmed better CO2-induced blood flow responses. Mechanisms include neuroprotection against oxidative stress and mitochondrial dysfunction.

In iPSC-derived neurons from AD patients, sildenafil lowered neurotoxic tau. Observational studies link frequent use to halved AD incidence, though RCTs are needed. Safe profile, oral dosing, positions it for Phase II/III trials.

For UK academics exploring neurodegeneration, this opens avenues in vascular neuroscience, aligning with Exeter's REACH Centre for Ageing and Cognitive Health research.

Riluzole: From Motor Neurone Disease to Alzheimer's Neuroprotection

Riluzole, approved for amyotrophic lateral sclerosis (ALS or motor neurone disease), inhibits glutamate release, mitigating excitotoxicity—a process where excess glutamate overstimulates neurons, leading to death in Alzheimer's.

Animal models show BDNF upregulation, glucose metabolism normalization, and tau/amyloid plaque reduction. A small Phase IIa trial hinted at cognitive stabilization. Safety requires renal monitoring but is tolerable long-term.

• Restores synaptic function in AD models.
• Modulates GABA/glutamatergic balance.
• Synergistic potential with vascular agents like sildenafil.

Stakeholder consultations ranked it third, valuing its neurodegeneration track record.

University of Exeter's Dementia Research Ecosystem

The University of Exeter anchors this work through world-class facilities like the REACH Centre, NIHR Exeter Biomedical Research Centre, and PROTECT study—monitoring 50,000+ participants for brain ageing insights. Funded over £15 million by NIHR, these hubs pioneer biomarkers, prevention, and care innovations.

Professors Ballard and Corbett's leadership exemplifies interdisciplinary collaboration, blending pharmacology, epidemiology, and patient voices. Exeter's output positions UK higher education as a dementia research powerhouse, attracting global talent. Recent feats include remote finger-prick Alzheimer's testing breakthroughs in January 2026.

Explore research jobs at leading UK universities like Exeter to contribute to such transformative studies.

UK Alzheimer's Landscape: Statistics and Societal Impact

Dementia claims 76,000+ UK lives yearly, surpassing cancer or heart disease, with £42 billion annual costs by 2024 projections. One in three born today faces lifetime risk; prevalence hits 1 in 14 over 65, 1 in 6 over 80. Disparities affect disadvantaged groups higher.

Repurposing addresses gaps: New drugs like lecanemab slow progression modestly but cost billions and take 15 years. Existing agents bypass this, promising equitable access via NHS.

Stakeholders—from Alzheimer's Society funders to caregivers—champion this, akin to aspirin's cardiovascular pivot.

Challenges in Drug Repurposing and Path to Clinical Trials

While promising, limitations persist: Observational biases, preclinical-to-human translation gaps, optimal dosing/timing unknowns. Zostavax needs RCT confirmation; sildenafil mixed epidemiology requires powering.

Exeter's PROTECT platform enables pragmatic trials: Annual online assessments track cognition, lifestyle, genetics in vast cohorts. NIHR HealthTech Centre advances diagnostics.

Regulatory hurdles demand Phase II safety/efficacy proofs before NHS integration.

Actionable Insights: Prevention Strategies Today

Beyond drugs:

• Get shingles vaccine if eligible (70+ or immunocompromised).
• Manage vascular risks: Exercise, Mediterranean diet, blood pressure control.
• Cognitive engagement: Learning, socialising via university lifelong programs.
• Monitor via GP; early biomarkers emerging from Exeter.

Integrate with lifestyle: Omega-3s link to lower risk per recent studies.

Careers in Dementia Research: Opportunities at UK Universities

This study fuels demand for experts in pharmacology, epidemiology, neuroscience. Exeter's ecosystem offers postdoctoral, lecturer positions in dementia prevention.

UK higher ed invests heavily: NIHR grants, Alzheimer's Society Centres of Excellence. Skills: Delphi analysis, trial design, bioinformatics.

Postdoc jobs, lecturer jobs, UK university roles abound. Platforms like Rate My Professor highlight leaders like Ballard.

Photo by Michał Parzuchowski on Unsplash

Future Outlook: Transforming Alzheimer's Prevention

Exeter's blueprint could redefine care: Population vaccination slashing incidence, repurposed pills stalling progression. Combined with AI diagnostics, gene therapies, a multi-pronged assault looms.

Global implications: Faster approvals via established safety accelerate worldwide adoption. UK academia drives this, fostering innovation hubs.

For engagement, explore higher ed jobs, university jobs, career advice. Share via comments below.