Healthy middle-aged people who are considered at increased risk of developing Alzheimer’s disease are set to receive an experimental drug as part of an international trial aimed at preventing dementia before symptoms appear.
The trial, being conducted with the involvement of an NHS trust, will recruit around 1,600 people aged between 55 and 80 from different parts of the world.
The first European participants are due to undergo screening on Monday through the Surrey and Borders Partnership NHS Foundation Trust.
Potential participants from across the UK will first be assessed to confirm that they have no existing memory problems. Those who meet the initial requirements will then undergo blood testing for p-tau217, a biomarker associated with cognitive decline and Alzheimer’s disease.
Previous research has suggested that people with the highest levels of p-tau217 have an estimated 78% likelihood of developing cognitive impairment within 10 years. Studies have also found that blood tests measuring the biomarker can detect Alzheimer’s disease with up to 95% accuracy.
The phase III study, known as the PrevenTRON trial, will examine whether trontinemab can prevent dementia from developing in people who have elevated p-tau217 levels and meet the other eligibility requirements.
Developed by Swiss pharmaceutical company Roche, trontinemab works by targeting amyloid plaques, toxic proteins that accumulate in the brain and contribute to the damage and eventual death of brain cells.
The drug has generated interest following early research suggesting it cleared amyloid plaques in nine out of 10 people with early-stage Alzheimer’s disease or mild cognitive impairment within 28 weeks.
Prof Ramin Nilforooshan, consultant psychiatrist and chief investigator of the PrevenTRON trial, said the research reflects a growing shift towards preventing Alzheimer’s rather than waiting until symptoms develop.
“For decades, research has focused on treating Alzheimer’s disease after symptoms appear. PrevenTRON addresses a different question, whether we can act earlier, before symptoms begin.”
He said research and trials such as PrevenTRON could potentially benefit millions of people affected by Alzheimer’s disease.
However, Nilforooshan stressed that trontinemab remains an experimental treatment and that the trial will determine whether it can actually prevent the condition.
“I’m not saying this trial is magic. It’s an investigational medicine. We need to wait and see: will it work or not?” he said.
At least 15 hospitals and clinics across the UK are expected to participate in the study by the end of the year, with recruitment being led by the Surrey and Borders Partnership trust.
The trial is expected to run for between four and six years. Participants will be randomly divided into groups receiving either trontinemab or a placebo and will be monitored throughout the study for signs of dementia.
Alzheimer’s disease is believed to begin developing in the brain years before people normally seek medical help for memory-related symptoms, with the underlying changes potentially occurring up to a decade earlier.
The condition is estimated to affect about one in 14 people aged over 65 and one in six people over the age of 80.
