What is the breakthrough Alzheimer's drug and when can it be accessed?

The first effective treatment for Alzheimer's could be available in the UK in a few years - ITV News Health Editor Emily Morgan reports

Doctors say they're at the "beginning of the end" in the search for effective Alzheimer's treatments, as a new drug shows it can slow symptoms.

This new drug, named Lecanemab, has recently undergone a series of clinical trials and shown that it can slow down the decline memory and mental agility in Alzheimer's patients.

Professor Nick Fox, director of the Dementia Research Centre, said: “I believe it confirms a new era of disease modification for Alzheimer’s disease.

“An era that comes after more that 20 years of hard work on anti-amyloid immunotherapies – by many many people – and many disappointments along the way.”

Here's what you need to know about the breakthrough drug.

What is this new Alzheimer's drug?

Lecanemab is designed to target and clear amyloid – one of the proteins that builds up in the brains of people with Alzheimer’s.

This has been found to slow decline in patients’ memory and thinking.Phased through three clinical trials, the results have been reported by Eisai, a Tokyo-based pharmaceutical company that has partnered with US biotech firm Biogen to develop lecanemab.

Eisai reported initial results in September from a trial on 1,795 participants with early Alzheimer’s disease.

Scientists found that, after 18 months, the drug slowed the disease progression by 27% compared with patients taking the placebo.

Experts are hailing it as long-awaited proof that Alzheimer’s disease can be treated.

Why is it significant?

Work into studying amyloid theory has been ongoing for a number of decades, and some experts believe this recent study represents "the beginning of the end".

Professor John Hardy, group leader at the UK Dementia Research Institute at University College London, said: “This trial is an important first step, and I truly believe it represents the beginning of the end.

“The amyloid theory has been around for 30 years so this has been a long time coming.

"It’s fantastic to receive this confirmation that we’ve been on the right track all along, as these results convincingly demonstrate, for the first time, the link between removing amyloid and slowing the progress of Alzheimer’s disease.

“The first step is the hardest, and we now know exactly what we need to do to develop effective drugs. It’s exciting to think that future work will build on this, and we will soon have life-changing treatments to tackle this disease.”

When will it be available?

Experts have warned that UK officials have a lot to do in order to deliver the drug, even if it gets regulatory approval.

Currently there are two methods to see if there is amyloid on the brain, either a scan of the brain or a biomarker test which is done through lumbar puncture.

It is thought that the use of blood testing to check for dementia isn't too far in the distant future - but current dementia services must rely on tests that are expensive and can have long waiting lists.

Private patients and those living near to big dementia services can access these diagnostic tests, but the vast majority of the public cannot, experts said.

They warned that unless there are big changes in diagnostic services, people could become ineligible for lecanemab treatment while on the waiting list for diagnosis because it can only be given to patients with mild disease – if their disease progresses to a moderate stage while on the waiting list, they will no longer be eligible for treatment.

Are there any side effects?

As with any new treatment or drug, side effects are a possibility and experts have stressed that more work still needed to be done to investigate them.

“The trial results have shown us that there is a risk of side effects, including brain bleeds in a small number of cases,” Professor Hardy said.

“This doesn’t mean the drug can’t be administered, but that will be important to have rigorous safety monitoring in place for people receiving Lecanemab, and further trials to fully understand and mitigate this risk.”

Are there quicker ways to diagnose Alzheimer's?

A separate study has identified a molecule in urine that can reveal early-stage Alzheimer’s disease.

The research suggests the finding could pave the way for an inexpensive and convenient test for the disease.

In other words, it may be possible that a simple urine test to analyse formic acid – a sensitive urinary biomarker – could reveal if someone has early-stage Alzheimer’s disease.

'It'd be like winning the lottery' - How promising new drug could bring hope to the 900,000 people in the UK with Alzheimer's

What exactly is Alzheimer's?

Alzheimer's disease is the most common cause of dementia in the UK, and its exact cause is not fully understood. Dementia is the name for a group of symptoms associated with an ongoing decline of brain functioning. It can affect memory, thinking skills and other mental abilities.

Symptoms are generally divided into three main stages.

In the early stages, where the main symptom is memory lapses, there are often signs of mood changes, such as increasing anxiety or agitation, or periods of confusion.

In the middle-stage, memory problems will get worse. Someone with the condition may find it increasingly difficult to remember the names of people they know and may struggle to recognise their family and friends.

And in later stages of Alzheimer's disease, the symptoms become increasingly severe and can be distressing for the person with the condition, as well as their carers, friends and family.

Hallucinations and delusions may come and go over the course of the illness, but can get worse as the condition progresses.

Sometimes people with Alzheimer's disease can be violent, demanding and suspicious of those around them.

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