Healthy middle-aged Britons will be offered an Alzheimer's drug in a new trial that seeks to prevent dementia before symptoms emerge. The first participants in Europe will be screened in Britain beginning Monday, with over 15 UK centers expected to join the global study. This approach marks a significant shift from treating the disease after its onset to intervening preventively.
The trial, named PrevenTron, will test the drug trontinemab, developed by Swiss pharmaceutical company Roche. Previous research indicated that trontinemab could clear toxic brain plaques in Alzheimer's patients after just three monthly infusions. Scientists will now investigate whether administering the drug before symptoms appear can stop the disease from developing altogether.
Professor Ramin Nilforooshan, chief investigator for the trial, described the study as a fundamental change in Alzheimer's research. "For decades, research has focused on treating Alzheimer's disease after symptoms appear," Nilforooshan said. "PrevenTron addresses a different question – whether we can act earlier, before symptoms begin."
Surrey and Borders Partnership NHS Foundation Trust is the first site in Europe to open the trial and will lead recruitment in Britain. Approximately 1,600 healthy adults aged between 55 and 80 will be recruited globally for the study, which is expected to last four to six years. Researchers estimate that Alzheimer's pathology can begin five to 10 years before individuals typically seek treatment for memory problems.
Potential participants will undergo memory tests to confirm they have no significant cognitive issues. They will then receive a blood test to measure p-tau217, a protein linked to Alzheimer's biological signs. Those with elevated levels will undergo further scans, including MRI and PET, before enrollment. Participants will be randomly assigned to receive either trontinemab or a placebo.
Trontinemab is designed to enter the brain more efficiently than existing Alzheimer's drugs and targets amyloid, a protein that accumulates in the brain and is associated with Alzheimer's development. Early results suggest it clears amyloid substantially faster than lecanemab and donanemab, two drugs that have shown success in slowing cognitive decline in patients with existing symptoms. While lecanemab and donanemab have been licensed in Britain, they were not approved for routine NHS use due to cost-effectiveness concerns.
Researchers will initially contact individuals who previously attended memory clinics but were found to have intact memory upon testing. The public can also contact the Surrey research team directly, with participants accepted from across the UK.
The trial launches amidst a broader effort to combat dementia in the UK. The Daily Mail and Alzheimer's Society have partnered on a campaign to defeat dementia, aiming to raise awareness, improve early diagnosis, and boost research and care. Dementia currently affects nearly one million people in the UK, a figure projected to reach 1.4 million by 2040.