BBC Panorama captures the promise and challenges of new Alzheimer’s treatments


By Alzheimer's Research UK | Monday 12 February 2024

Monday’s BBC Panorama episode – “Alzheimer’s: A Turning Point?” – focused on the potential arrival of two new breakthrough treatments for Alzheimer’s disease, lecanemab and donanemab. In the past two years, both drugs have been shown to slow down the progression of the early stages of the disease – which is the most common form of dementia.

The documentary follows the BBC’s Medical Editor, Fergus Walsh, as he meets people with Alzheimer’s who have been taking the drugs by participating in clinical trials. Neither drug currently has a licence to be prescribed in the UK outside of these trials, but decisions on this are expected in the coming months.

Dawn, who’s 62 and from Hampshire, is currently taking donanemab. On the show, she explained that she is hopeful the drug will help her. “If it slows it down, then I’ll be able to function as I’d like to and do some of the things I’d still like to do” she said.

Fergus also spoke to Consultant Neurologist Dr Cath Mummery, Head of Clinical Trials at the Dementia Research Centre at University College London, and who spoke at Alzheimer’s Research UK’s 2023 Clinical Conference. Although the effects of these drugs are modest – they appear to slow cognitive decline by between about a quarter and a third over 18 months Dr Mummery said this would make a meaningful difference to individual patients, giving them “about five months at a higher function.”

Also on the programme, Alzheimer’s Research UK’s Executive Director of Research & Partnerships, Dr Susan Kohlhaas, raised our concerns that the NHS is not yet ready to roll out the drugs, should they be approved. To be eligible for either drug, people would have to be in the early stages of Alzheimer’s and have had a PET scan or lumbar puncture to confirm high levels of amyloid – the hallmark protein of Alzheimer’s – in their brain. But currently, only 2% of people with dementia receive either of these “gold standard” methods of diagnosis. “This is a major issue that we need to start addressing now.” she said.

If these drugs are approved, the NHS faces logistical and financial hurdles in making sure they can be delivered quickly to people who are eligible. Dr Kohlhaas called for “a clear plan from the NHS about how they’re going to scale up services,” as well as sustained investment to make the dementia diagnosis pathway fit for now and fit for the future.

If you’ve watched the programme, or read about it in the news, we understand that you might have some questions. Below you’ll hopefully find the answers you need, but if not, please contact our Dementia Research Infoline on 0300 111 5 111 or email

How are these treatments different to what is currently available?

Current drugs like donepezil (Aricept) and memantine (Ebixa or Axura) are known as ‘symptomatic’ treatments – they allow our brain cells to communicate better so can counteract the damage caused by diseases like Alzheimer’s, but don’t target the underlying disease itself.  Although these treatments can make a big difference to somebody’s quality of life, they can’t slow or stop the underlying damage getting worse, and their benefits usually only last for around a year. By directly targeting amyloid, lecanemab and donanemab slow down the disease, and will hopefully allow people to live independently for longer.

Who will be eligible for lecanemab and donanemab?

These drugs have so far only shown effectiveness in people in the early stages of Alzheimer’s disease. People included in the trials had either a condition called ‘mild cognitive impairment’, or mild Alzheimer’s disease, that had been confirmed by a test of their spinal fluid, or a PET brain scan that showed a build-up of amyloid in their brain. Many experts suspect they would be unlikely to work in later stages of the disease, although this hasn’t been tested in trials yet.

Is it true that tens of thousands of people could miss out on treatment because the NHS isn’t ready?

Yes, we estimate that tens of thousands of people could miss out on treatment because – as things stand – they won’t be able to access the diagnostic tests that could tell if they are suitable for the treatments. The diagnostic tests, a PET brain scan or a lumbar puncture to collect spinal fluid, are currently offered to fewer than 2% of people in the UK seeking a dementia diagnosis. Insight from clinicians across the UK suggests the current set-up would be able to diagnose and treat around 2,000 patients a year. However, this contrasts with recent estimates by clinicians that around 30,000 patients a year could be clinically suitable for these treatments if they’re approved.  This means that unless NHS diagnostic capacity is significantly increased, around 28,000 people could miss out on treatment. We would stress these are estimates based on what we currently anticipate, but the gap between current capacity and future demand is significant.

What are the side effects of these treatments?

These treatments come with a potential side effect called ARIA (which stands for ‘amyloid related imaging abnormalities’). These are changes to brain structure, swelling (ARIA-E) and bleeds (ARIA-H) seen on MRI brain scans, which – for some – can be serious.

Roughly 1 in 8 people who received lecanemab were found to develop ARIA, however most (80%) of the people who developed ARIA did not have symptoms, and overall, less than 1 in 30 had any symptoms like as headaches or confusion. 12.6% and 17.3% of people receiving lecanemab in trials developed ARIA-E and ARIA-H, respectively.

In those patients receiving donanemab, brain swelling (ARIA-E) was seen on the scans of one in four participants, with one in 20 experiencing symptoms, and less than two in every 100 participants experienced serious brain swelling after taking donanemab. 31% of the participants developed bleeds (ARIA-H), compared to 14% of those who received the placebo.

How are these treatments given?

Lecanemab requires an infusion every two weeks, while donanemab requires infusions every month – meaning that people would need to get to a hospital or specialist centre to receive treatment. People receiving these treatments will also need to be closely monitored for any side effects, and this means having regular MRI brain scans.

When could lecanemab and donanemab become available?

Alzheimer’s Research UK hopes that the first regulatory decision by the will be made in the first half of 2024. If they are approved, they will still need to be assessed for cost-effectiveness by NICE, and we anticipate these drugs won’t be available in the NHS before the end of 2024 at the very earliest – and we don’t know how widely available they will be. Our video explains how a drug moves from clinical trials into routine use.

Can I take part in research for new treatments?

Yes, we need people with a diagnosis of dementia to get involved, and to take part in trials of new treatments and diagnosis methods. Progress made with lecanemab and donanemab wouldn’t have been possible without people taking part in research studies, and there are plenty of opportunities to take part in current research studies. People without dementia can take part in research too, anyone over the age of 18 living in the UK can sign up for dementia research and be matched with studies they are suitable for. You can find out more about taking part and register here: Take part in dementia research – Alzheimer’s Research UK (


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  1. Paula Stanton on 20th February 2024 at 7:21 pm

    This sounds amazing, I am waiting for my dad to have the tests ,he has got a ct scan booked then await for an appointment in the memory clinic, so any break through is a big achievement.

  2. Alan Nicholson on 20th February 2024 at 7:49 pm

    If these new treatments are approved in the UK will my wife be able to obtain them privately in advance of NICE approval.

    • Alzheimer's Research UK on 21st February 2024 at 1:55 pm

      Hi Alan, thanks for your comment. In theory, yes – if the MHRA approve the drug, lecanemab will become available for private medical services to offer as soon as stock reaches in the UK. However, we’re not sure yet which services will offer lecanemab, and how long it will take them to set up clinics and train staff to deliver it.

  3. Pippa on 22nd February 2024 at 8:27 pm

    Hi my nan had dementia and she sadly passed away on 15th October 2023 how does dementia happen.

  4. Wendy Gittens on 27th February 2024 at 9:13 am

    I see there is mention that these new drugs would give individuals who take them about 5 months of higher function, does this mean that after this time they will start to decline and the effects of the drugs will no longer be effective in slowing the decline?

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