Alzheimer’s: 3 Existing Drugs Show Promise for Treatment & Prevention
Researchers are exploring a potentially faster, safer and more affordable path toward treating or preventing Alzheimer’s disease by examining existing, approved medications for new applications. Instead of the lengthy and costly process of developing drugs from scratch, scientists are investigating whether medicines already used for other conditions could offer protection against the devastating effects of this disease.
The Search for Repurposed Treatments
Why Repurposing Matters
Dementia is the leading cause of death in the UK, currently affecting around one million people. The statistics are sobering: one in three people born today will likely develop dementia during their lifetime, and currently, there is no cure.
A study led by the University of Exeter and funded by Alzheimer’s Society, published in Alzheimer’s Research and Therapy, identified three promising candidates for repurposing. An international panel of 21 dementia specialists, including individuals affected by the disease, evaluated 80 existing medications to determine which held the most potential.
The Top Three Candidates
The panel selected three drugs for further research, each chosen because it targets biological processes linked to Alzheimer’s, has shown encouraging results in laboratory and animal studies, and is considered safe for older adults. These are:
- Shingles vaccine (Zostavax): Research suggests a possible connection between the shingles virus and dementia. The vaccine interacts with the immune system in a way that may help counter harmful changes associated with Alzheimer’s.
- Sildenafil (Viagra): Studies indicate it may protect nerve cells and reduce the buildup of tau, a protein that accumulates abnormally in Alzheimer’s. Mouse studies showed improved thinking and memory, potentially due to increased blood flow to the brain.
- Riluzole: Currently used to treat motor neurone disease, riluzole has shown improved cognitive performance and lowered tau levels in animal studies.
Shingles Vaccine Shows Promise
Among the three candidates, the shingles vaccine emerged as particularly promising. It requires only two doses and has a well-established safety record. Previous research suggests individuals who received the vaccine were approximately 16% less likely to develop dementia.
What’s Next?
Experts are now calling for clinical trials to determine whether these medications can truly benefit individuals with Alzheimer’s or those at risk of developing the disease. Researchers hope to launch a large UK clinical trial of the shingles vaccine, utilizing PROTECT – an online registry where volunteers provide annual health and lifestyle information and participate in brain health research.
Five additional medications – fingolimod, vortioxetine, microlithium, dasitinib, and cytisine – were shortlisted but did not meet the criteria to be designated as ‘priority candidates’ at this stage.
Frequently Asked Questions
What is drug repurposing?
Drug repurposing involves investigating whether existing medications, already approved for other conditions, could be used to treat or prevent Alzheimer’s disease.
Why is drug repurposing being considered for Alzheimer’s?
Creating new drugs can take a long time and cost a lot of money, with no guarantee of success. Repurposing existing drugs could be a faster, safer, and more affordable approach.
What were the three priority drugs identified in the study?
The three priority drugs are the shingles vaccine (Zostavax), sildenafil (Viagra), and riluzole, a medication used to treat motor neurone disease.
Given these initial findings, what role do you think collaborative research efforts, involving specialists and those directly affected by dementia, will play in accelerating the development of new treatments?