EU regulator rejects Alzheimer's drug lecanemab

The European Medicines Agency (EMA) has refuse the license Alzheimer's treatment that slows cognitive decline.

The EMA said the benefits of lecanemab are not outweighed by the risk of serious side effects, particularly bleeding and swelling in the brain.

The UK medicines regulator, the MHRA, is still considering whether to license it, and a decision is expected soon. This drug was approved in the United States earlier this year.

In trials, lecanemab was shown to slow cognitive decline by nearly a quarter in patients in the early stages of Alzheimer's.

Alzheimer's researchers recommend trial results “as history” because no previous medicine had convincingly shown that the underlying mechanism of disease could be reduced.

Lecanemab works by removing a hard protein called amyloid, which builds up in the brains of Alzheimer's patients.

Even if a drug is to be approved in the UK, it will be up to health bodies – such as the National Institute for Health and Care Excellence (NICE) and the Scottish Medicines Consortium (SMC) – to decide whether the drug represents value. for money and should be recommended to patients.

Lecanemab costs around £20,000 per patient per year in the US.

The EMA said that although patients given lecanemab, whose name is Leqembi, delayed cognitive decline, the effects were small.

It said the most important safety concern was the frequent occurrence of amyloid-related imaging abnormalities (ARIA), which involve swelling and bleeding in the brain.

The EMA said: “Although most cases of ARIA in the main study were mild and did not involve symptoms, some patients had serious events, including severe bleeding in the brain that required hospitalization.”

Overall, it found the benefits of the treatment were insufficient to outweigh the risks.

Professor Tara Spiers-Jones, president of the British Neuroscience Association, said the EMA's decision would come as a “disappointment to many”.

But he said there are reasons to stay hopeful.

“Lecanemab has shown that it is possible to slow the progression of the disease, and the research is working. We now need to step up our efforts to find new and safer treatments,” said Prof Spiers-Jones.

Professor John Hardy, professor of neuroscience and team leader at the UK Institute for Dementia Research, University College London (UCL), said the decision could have unintended consequences.

“I'm sure now we'll see rich people with early stage Alzheimer's flying to the US or other places for treatment.”

BBC Panorama followed patients on lecanemab and another new drug, donanemab.

In the programme, which aired earlier this year, Prof Cath Mummery, a neurologist and head of clinical trials at the Dementia Research Center at UCL, said that although the benefits of the drugs were small, they represented a “transformation”.

He added: “I don't think they are false hopes. For the first time, we have drugs that show that you can reverse the course of Alzheimer's, and that is extraordinary.”

The Alzheimer's Society said that while it respected the drug's decision, it would be “really difficult news for people in Europe who may have been eligible for this drug”.

“Whatever decisions the regulators make, we're still in for an important and exciting time,” said Mark MacDonald, from the community.

“There are currently 164 active clinical trials for Alzheimer's disease, and we expect that more treatments will be submitted for MHRA approval in the future.”