International Clinical Study: 1,600 People Tested to Prevent Alzheimer's Before Symptoms Appear

A new large-scale international clinical study is investigating a different approach to current Alzheimer's treatments: intervening before memory symptoms appear. Approximately 1,600 people aged between 55 and 80, with no visible symptoms, will be assessed starting Monday to identify a biomarker associated with an increased risk of cognitive decline and Alzheimer's, according to The Guardian.

The study is coordinated by Surrey and Borders Partnership NHS Foundation Trust, with the first European participants being tested from Monday. Those included will first be assessed to confirm they have no memory problems, then given a blood test to measure levels of a protein called p-tau217 – a biomarker capable of anticipating cognitive decline and the development of Alzheimer's disease.

Previous research has shown that people with the highest levels of p-tau217 have an estimated 78% risk of developing cognitive impairment within the next 10 years. Other studies have indicated that this type of blood test can identify Alzheimer's with an accuracy of up to 95%.

A drug tested before symptoms appear

The study, called PrevenTRON, is in phase III and will examine whether administering the drug trontinemab to people with elevated p-tau217 levels can prevent the onset of dementia. Trontinemab, developed by Swiss company Roche, targets amyloid plaques – toxic accumulations of proteins in the brain that damage nerve cells and, over time, destroy them.

The drug was considered promising after initial research showed that, within 28 weeks, it cleared amyloid plaques in nine out of ten people in the early stages of Alzheimer's or with mild cognitive impairment.

Professor Ramin Nilforooshan, consultant psychiatrist and principal investigator of the PrevenTRON study, explained the shift in research direction: "For decades, research has focused on treating Alzheimer's disease after symptoms appear. PrevenTRON asks a different question: can we intervene earlier, before symptoms emerge?"

However, he stressed that the treatment remains experimental: "I'm not saying this study is something magical. It's an experimental drug. We need to wait and see: will it work or not?" Nilforooshan told The Telegraph.

The study will run for up to six years

At least 15 hospitals and clinics across the United Kingdom are set to join the study by the end of the year, with recruitment being coordinated by Surrey and Borders Partnership. The research is estimated to last between four and six years.

Participants will be randomly divided into two groups: some will receive trontinemab, whilst others will receive a placebo. Researchers will then monitor them to see whether and how quickly signs of dementia emerge.

According to specialists, the pathological processes specific to Alzheimer's disease can begin in the brain up to 10 years before a person typically seeks medical help for memory problems. The disease currently affects approximately one in 14 people aged over 65, and one in six aged over 80.

Those interested in taking part in the assessment can contact the Surrey and Borders Partnership research team.