Drug donanemab seen as turning point in dementia fight

Results out today confirm that the drug donanemab, hailed as a turning point in the fight against Alzheimer's, slows cognitive decline by about a third.

Mike Colley, who is 80, is one of only a few dozen patients in the UK to take part in the global trial, now published in the journal JAMA.

He gets an infusion each month at a clinic in London and says he is "one of the luckiest people you'll ever meet".

The antibody treatment helps in the early stages of the disease.

It works in Alzheimer's disease, not in other types of dementia, such as vascular dementia.

That is because it is designed to clear away one of the key features of Alzheimer's disease - a substance called amyloid that builds up in the spaces between brain cells.

Mike and his family noticed he was having problems with memory and decision-making, not long before he started on the trial.

His son, Mark, said it was very hard to watch at the beginning: "Seeing him struggle with processing information and solving problems was very hard. But I think the decline is reaching a plateau now."

Speaking exclusively to the BBC, Mike, who is from Kent, said: "I feel more confident every day."

Donanemab, made by Eli Lilly, works in the same way as lecanemab - developed by companies Eisai and Biogen - which created headlines around the world when it was proven to slow the disease.

Although extremely promising, these drugs are not cures or risk-free treatments.

Brain swelling was a common side-effect in up to a third of patients in the donanemab trial. For most, this resolved without causing symptoms. However, two volunteers, and possibly a third, died as a result of dangerous swelling in the brain.

Another antibody Alzheimer's drug, called aducanumab, was recently rejected by European regulators over safety concerns and a lack of evidence that it was effective enough for patients.

In the donanemab trial, researchers examined 1,736 people aged 60 to 85 with early-stage Alzheimer's.

Half of them received a monthly infusion of the treatment and the other half were given a dummy drug, also known as a placebo, over 18 months.

Amyloid is just one part of the complex picture of Alzheimer's, and it is unclear if the treatment will continue to make more difference over a longer period, experts caution.

The drug's effects may be modest, but the results provide further confirmation that removing amyloid from the brain may change the course of Alzheimer's, and help people affected by this devastating disease if they're treated at the right time, they say.

Prof Giles Hardingham from the UK Dementia Research Institute, said: "It is terrific to see these results published in full today. We have waited a long time for Alzheimer's treatments, so it's really encouraging to see tangible progress continuing to gather pace in the field. We're on the edge of exciting and significant change in the landscape of treatment for people affected by - or at risk of -dementia."

Dr Susan Kohlhaas, from Alzheimer's Research UK, said: "Today's announcement marks another milestone. Thanks to decades of research, the outlook for dementia and its impact on people and society is finally changing, and we're entering a new era where Alzheimer's disease could become treatable."

Mike Colley turned 80 in April. At his birthday party, he surprised his family by singing My Way in front of 40 guests.

He told BBC News: "That's the confidence I have now. I'd never have done that even 12 months ago."

His son Mark added: "I never thought I would see my dad so full of life again. It was an incredible moment."

Dr Emer MacSweeney, consultant neuroradiologist and medical director at Re:Cognition Health, led the trials of donanemab in the UK.

She said: "This is really significant and one of the biggest breakthroughs."

The Alzheimer's Society said: "This is truly a turning point in the fight against Alzheimer's and science is proving that it is possible to slow down the disease."

Around 720,000 people in the UK might potentially benefit from these emerging new Alzheimer's disease treatments if they're approved for use, but the Alzheimer's Society said the NHS is "simply not ready to deliver them".

Kate Lee, a spokeswoman for the charity, said: "Timely, accurate diagnosis is key, and currently only 2% of people in England and Wales receive their diagnosis through the specialist investigations needed to be eligible for these treatments.

"Alongside this, these emerging Alzheimer's disease drugs require regular infusions and monitoring, and the NHS is not yet equipped to do this at scale."

Lecanemab costs around $27,500 (£21,000) in the US, where it is licensed.

It is not clear how much Donanemab may cost and how long it might take to get approval in the UK, but Alzheimer's experts said having two drugs would help promote competition on price.

The UK's drug's watchdog NICE says it has already started work on its appraisal of donanemab for treating mild cognitive impairment or mild dementia caused by Alzheimer's disease.

"Our aim is to produce recommendations on its use in the NHS as close as possible to it receiving its UK licence," said a spokesperson.