'Encouraging' Alzheimer's tests tame brain disease in mice

About 55 million people worldwide suffer from dementia, with Alzheimer's disease the most common type. Getty Images

Alzheimer's researchers have found a "very encouraging" way of taming brain disease in mice, which could point the way to halting dementia.

Scientists in Germany said brain cells typical of Alzheimer's looked healthy again after the mice were given a protein drug in the lab.

The drug "completely suppressed" the effects of a harmful molecule called amyloid beta, researchers at the Technical University of Munich said.

"We are still a long way from a therapy that can be used in humans, but the results in animal experiments are very encouraging," said one of the researchers, Benedikt Zott.

Health experts hope the protein "can halt the progression of the severe neurodegenerative disease at an early stage", the university said.

It said the treatment used on mice was a "promising, preventive therapeutic approach" in the fight against Alzheimer's.

However, it is "still unclear whether the effect can be achieved in human patients outside the laboratory".

Alzheimer's disease is the most common form of dementia, which affects about 55 million people worldwide, mostly aged 65 or older.

There is currently no cure, although drugs can treat symptoms such as memory problems and confusion.

New UK drug

Regulators in Britain approved an Alzheimer's drug on Thursday that they say "shows some evidence of efficacy in slowing progression of the disease".

The drug, lecanemab, is made by Japanese company Eisai and has been approved for people in the early stages of Alzheimer's.

It works by reducing clumps of the amyloid beta protein that can form in the brain, ushering in the effects of Alzheimer's.

Private patients

During the UK lecanemab trials, injections every two weeks led to "a statistically significant reduction in clinical decline" after 18 months.

The drug has been licensed for use in the UK but a separate announcement that the state-run National Health Service would not be providing it to patients has been criticised.

Alzheimer’s Research UK described the NHS announcements around lecanemab as “deeply disappointing” and warned it would be available only to those who could pay privately.

The National Institute for Health and Care Excellence (Nice) said the benefits of lecanemab were “just too small to justify the significant cost to the NHS”.

Patients who can afford the treatment will have to undergo genetic screening and will not be eligible if they have particular genes that could cause swelling or bleeding.

"We’re assured that, together with the conditions of the licence approval, the appropriate regulatory standards for this medicine have been met," said Julian Beach from the UK regulator.

A typical sign of Alzheimer's in its early stages is that the amyloid beta molecules make brain cells hyperactive, the German scientists said.

After the injections in mice, the "previously hyperactive brain cells could no longer be distinguished from healthy nerve cells".

Finding ways to detect Alzheimer's early, before the symptoms begin to show, is another major area of research.

A new Alzheimer's blood test was revealed in January, which scientists hope could be just as accurate and less onerous than "gold standard" tests involving scans or lumbar punctures.