Hyped-up Alzheimer’s drug: too early to tell if this really is a breakthrough

An early trial of an Alzheimer’s drug suggests it may benefit patients in the earliest stages of the disease.

The drug, an antibody called aducanumab, can break down the amyloid protein that builds up in abnormal amounts in the brains of patients with Alzheimer’s, according to a study published in Nature.

The study was small, following only 165 people, and aimed merely to assess the safety of the treatment.

An ‘exploratory analysis’ of the data appeared to show the drug slowed mental decline. Two larger trials, of 2,700 people in 20 countries, are being planned.

The drug is not without side effects. The patients who received the highest dose showed higher rates of brain swelling.

Alfred Sandrock, senior author of the paper, said: ‘We are pretty certain of the fact that the antibody reduces the amyloid plaques and in some ways gets rid of the majority of it.

‘That’s important because if we really want to treat Alzheimer’s at even the very earliest stages, then we felt it was important for our antibody to remove the plaque that’s already there.’

Instant analysis
You could be forgiven for inferring that a full-on cure has been found for Alzheimer’s disease after reading press coverage on this study. However, there is very little mention of the drawbacks: for example, 40 out of the 165 people given the drug dropped out for reasons including side effects such as headaches. This is almost a quarter of what is already a small number of subjects.

There is no denying that this drug may well prove to be safe and useful in the treatment of Alzheimer’s disease, and further trials are now being carried out. But this can’t yet be hailed as a breakthrough. As Dr Tara Spires-Jones, of the Centre for Cognitive and Neural Systems at the University of Edinburgh, told the BBC: ‘I am cautiously optimistic about this treatment, but trying not to get too excited because many drugs make it through this early stage of testing then go on to fail in larger trials.’
MB
Research score: 2/5