A new drug, lecanemab, has been hailed as a momentous breakthrough in the fight against Alzheimer's disease, becoming the first treatment to slow the destruction of the brain. The research, published in the New England Journal of Medicine, ends decades of failure and signals a new era of drugs for the most common form of dementia.
The antibody therapy works by clearing sticky amyloid plaques from the brain, a hallmark of Alzheimer's. In a trial of 1,795 volunteers with early-stage Alzheimer's, fortnightly infusions of lecanemab slowed cognitive decline by around a quarter over 18 months. However, the effect is modest, with patients on the drug scoring 0.45 points better on an 18-point symptom scale.
Experts describe the results as historic but caution that the drug is not a cure. 'It's a small effect, but even though it is not dramatic, I would take it,' said Prof Tara Spires-Jones of the University of Edinburgh. The drug also carries risks, including brain bleeds in 17% of participants and brain swelling in 13%, leading to 7% stopping treatment.
Regulators in the US are assessing lecanemab for approval, with the developers, Eisai and Biogen, planning to seek approval in other countries next year. David Essam, 78, from Kent, who took part in the trial, said: 'If somebody can slow it down and eventually stop it all together that would be brilliant.'
With over 55 million people worldwide living with Alzheimer's, projected to exceed 139 million by 2050, the drug offers hope. Dr Susan Kohlhaas of Alzheimer's Research UK called it 'a little bit of a foothold' for future treatments. The impact on daily life remains debated, but researchers believe it could provide an extra 19 months of independent living, though longer trials are needed.
