Alzheimer's 'wonder drug' could delay disease for three years - 90% of brain damage vanished in new trial

A 'wonder drug' that can stave off Alzheimer's disease could delay the life-ruining symptoms for up to three years, striking new data shows.Previous trials of donanemab have found that the benefits, which occur in 35 per cent of patients, only last for around four to seven months. But a new study presented at the Alzheimer's Association International Conference (AAIC) in London showed it not only postponed memory and thinking problems, but also protected against damage associated with the disease.The treatment - delivered via infusion - has been licensed for use in the UK since 2024 but has not been made available on the NHS.Health watchdog the National Institute for Health and Care Excellence (NICE) deemed its benefits 'too small' to justify the cost.There have also been serious concerns about the side effects of the drug, which can cause severe brain bleeding.Three deaths related to this complication have been reported in participants who took part in previous clinical trials of the drug. The fatality rate was less than two in a thousand of the participants who took part in the trial. The drug appeared to protect against dementia for three years Everyone experiences dementia differently. Use this checklist to help you make a note of your symptoms before you talk to your GP.But the new findings, presented at the could strengthen the argument that donanemab is good value for money. The new research followed 1,200 dementia patients, roughly half of which were treated with donanemab for 18 months.Scientists compared their results with a matched group of similar patients who had not received the drug, assessing them using a dementia rating scale that tests memory and thinking.At the end of the 18 months, there was a significant difference between patients who had been given donanemab and those who hadn't. After three years, the gap between the two groups had doubled.The researchers also noted that the drug appeared to suppress tau, a protein found naturally in the brain, that is linked to Alzheimer's. It normally helps brain cells function properly, but decades of research has found levels of tau tend to increase in those diagnosed with the disease.Scientists can identify higher levels of tau by looking for a compounds in the blood called p-tau217.After 17 months of treatment, levels of p-tau217 fell significantly, yet continued to rise in the patients who were not given the drug.Additionally, brain scans showed that the level of harmful amyloid plaques - the second hallmark of Alzheimer's - had reduced by 90 per cent in those with mild cognitive impairment. Hilary Evans-Newton, the chief executive of Alzheimer's Research UK, noted that the findings suggest that the benefits of donanemab 'can continue for years after treatment ends'.'This strengthens the growing evidence for both the medicines already licensed in the UK, donanemab and lecanemab, that they can slow the progression of Alzheimer's disease over the longer term, and have greater benefit when started early in the course of the disease,' she said.Dr Richard Oakley, Associate Director of Research and Innovation at Alzheimer's Society said: 'Donanemab became the second treatment approved in the UK to tackle early Alzheimer's disease but as yet is not available through the NHS.'Over time, as evidence grows, new safety findings and delivery methods could be grounds for future hope.'But, the reality is that even if donanemab was made available on the NHS tomorrow, our healthcare system isn't ready to deliver it. At any one time, a third of people with dementia in the UK do not have a diagnosis, and services aren't equipped with the staff and tools needed to diagnose more people at pace and monitor people on new treatments were they available.''We need to see urgent investment in preparing health systems for delivering new treatments, coupled with clear national targets on early and on accurate diagnosis to ensure the right people can access the right treatments at the time when they're most effective.'We also need to see studies within the NHS using donanemab and lecanemab to understand more about how these treatments can be most effectively delivered and monitored.'There are an estimated one million people in the UK living with dementia - of which Alzheimer's is the most common type - and by 2040 that figure is expected to climb to 1.4 million. In April, a major review found that donanemab may offer only limited benefits for patients. Researchers from the Cochrane Collaboration reviewed 17 trials involving more than 20,000 patients taking drugs designed to remove amyloid protein from the brain.They concluded that while the treatments can slow the progression of Alzheimer's disease, the effect is 'well below' what would be needed for patients to notice a clear benefit.The drug was also linked to risks, including brain swelling and bleeding - although it is claimed that experts have been working to make the drug 'more tolerable'. Donanemab requires regular infusions - every two to four weeks - with private treatment costing tens of thousands of pounds a year.