Healthy middle-aged Britons to be offered Alzheimer's drug in trial aiming to prevent dementia

Middle-aged people with no memory problems will be prescribed an Alzheimer’s drug in a trial aiming to prevent dementia.The first participants in Europe will be screened in Britain from Monday, with more than 15 UK centres expected to take part in the global study.Previous research on patients with Alzheimer’s suggested the treatment could clear toxic brain plaques after just three monthly infusions.Now scientists will test whether giving the drug, called trontinemab, before symptoms appear can stop Alzheimer’s developing in the first place.If it proves successful it has the potential to transform how the disease is treated.Ultimately, people at high risk could be prescribed drugs preventively in mid-life, in an approach experts have compared to ‘statins for the brain’.The launch comes as the Daily Mail and Alzheimer's Society have partnered in a drive to defeat dementia, which claims 76,000 lives a year as Britain’s biggest killer.The Defeating Dementia campaign aims to raise awareness of the disease, in an effort to increase early diagnosis, boost research and improve care. Previous research on patients with Alzheimer’s suggested the treatment could clear toxic brain plaques after just three monthly infusions.Professor Ramin Nilforooshan, chief investigator for the PrevenTron trial, said the study marked a fundamental shift from waiting for memory problems to emerge to trying to prevent them in the first place.He said: ‘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.’Surrey and Borders Partnership NHS Foundation Trust is the first site in Europe and the third in the world to open the trial and will lead recruitment in Britain.More than 15 UK hospitals and clinics are expected to take part.Around 1,600 healthy adults aged between 55 and 80 will be recruited internationally for the trial, which will last four to six years.Professor Nilforooshan said Alzheimer’s pathology was thought to begin five to 10 years before people typically sought treatment for memory problems.Potential participants will first undergo memory tests to establish that they have no significant cognitive problems.They will then be given a blood test measuring p-tau217, a protein that can reveal biological signs of Alzheimer’s before symptoms emerge.Those whose levels are elevated and fall within the range required by the trial will undergo further investigations, including MRI and PET scans, before being enrolled.Participants will be randomly assigned to receive either trontinemab or a placebo, with researchers following them for between four and six years to discover whether the drug can prevent or delay memory and thinking problems.Professor Nilforooshan told the Telegraph: ‘I’m not saying this trial is magic. It’s an investigational medicine. We need to wait and see: will it work or not?’Trontinemab, developed by Swiss pharmaceutical company Roche, has been designed to enter the brain more efficiently than existing Alzheimer’s drugs.The drug attacks amyloid, the sticky protein which accumulates in the brain and is associated with the development of Alzheimer’s disease.The clearance appears substantially faster than with lecanemab and donanemab, the first drugs proven to slow the progression of Alzheimer’s disease, which typically take more than a year to remove similar levels of amyloid.Trials of lecanemab and donanemab found the drugs slowed cognitive decline by 27 per cent and 35 per cent respectively in patients who already had symptoms.Both have been licensed in Britain but rejected for routine NHS use after officials ruled they were not cost-effective.Researchers will initially approach people who previously attended memory clinics but were discharged after testing found their memory was intact.People can also approach the Surrey research team directly, with participants accepted from across the country.Almost one million people in the UK are living with dementia, with the total forecast to reach 1.4 million by 2040.