Shingles Vaccine and Viagra Show Promise as Alzheimer's Treatments

A groundbreaking study has identified three existing medications that could be repurposed to combat Alzheimer's disease, potentially offering a faster and more affordable path to treatment than developing new drugs from scratch. With dementia affecting one million people in the UK and one in three people born today expected to develop it, finding effective treatments is increasingly urgent.

Researchers from the University of Exeter led an international panel of 21 dementia specialists who evaluated 80 existing medications. They identified three priority candidates: Zostavax (shingles vaccine), sildenafil (Viagra), and riluzole (motor neurone disease medication). Each drug targets biological processes linked to Alzheimer's and has shown encouraging results in laboratory and animal studies.

The shingles vaccine emerged as the strongest candidate, requiring only two doses and having an established safety record. Previous research indicates vaccinated individuals were 16% less likely to develop dementia, possibly due to immune system interactions that counter harmful changes associated with Alzheimer's. Viagra showed promise for protecting nerve cells and reducing tau protein accumulation, while also improving blood flow to the brain in mouse studies.

Drug repurposing offers significant advantages over traditional drug development, which typically takes 10-15 years and costs billions with no guarantee of success. Since these medications are already approved and widely used, they could potentially reach patients much faster if clinical trials prove successful. Researchers are now calling for large-scale human trials to determine whether these promising laboratory findings translate into real-world benefits for people with or at risk of developing Alzheimer's disease.