Research

What is donanemab?

The Medicines and Healthcare products Regulatory Agency (MHRA) has approved donanemab (marketed as Kisunla in the UK) as a treatment for some people with early-stage Alzheimer’s disease. The drug can slow down the decline in memory and thinking skills of people living with early Alzheimer’s disease.

NICE has now published a second version of its draft guidance, where its recommendation remains that donanemab not be provided through the NHS. NICE has extended its review and stakeholder consultation to invite further comments and to consider additional data. A final decision will be made as to whether donanemab can be provided through the NHS later this year. 

Another similar drug called lecanemab (marketed as Leqembi) has also been approved by the MHRA.  Similarly NICE has extended its review and stakeholder consultation of lecanemab and we also expect a final decision as to whether it will be provided through the NHS later this year. 

What is donanemab?

Donanemab (brand name Kisunla) is a disease-modifying drug, which means that it was developed to tackle the causes of Alzheimer’s disease rather than only relieving the symptoms.  

Donanemab is given to patients intravenously, which means into a vein through a drip bag. It is an immunotherapy drug developed by a pharmaceutical company called Eli Lilly. Immunotherapy drugs are already used in medicine for treating different diseases, like cancers. They tell the body’s immune system to attack foreign cells or proteins and get rid of them so they can’t cause any more problems.

In the case of donanemab, it teaches the immune cells to recognise and remove a protein called amyloid, which builds up in the brains of people with Alzheimer’s disease. In the trial three-quarters of the people taking donanemab had amyloid successfully cleared from their brains by the end of the trial.

The amyloid protein build-ups are thought to be toxic to brain cells, causing them to get sick and eventually die, leading to the symptoms of Alzheimer’s disease. The importance of this protein in the development of Alzheimer’s disease was discovered by Alzheimer’s Society-funded research led by Professor Sir John Hardy over thirty years ago. It laid the foundations for billions of pounds of investment into many drugs like donanemab, with 127 other drugs currently being tested in clinical trials.

Does donanemab work?

Donanemab slowed how fast memory and thinking get worse by more than 20%. The evidence from a trial called TRAILBLAZER ALZ2 showed that the earlier in the disease the treatment was given, the greater the benefit. This meant that there was more slowing in memory and thinking decline in people with fewer changes in their brains associated with Alzheimer’s disease at the start of the trial.

Also, after one year on donanemab, nearly half of the people taking it had no decline in memory and thinking skills.  

People taking donanemab had a 40% reduction in the decline of their ability to carry out daily activities, such as managing finances, driving and carrying out hobbies.  

These are exciting results, but we don’t fully know what this will mean in the long term for people who have taken donanemab as the trial only lasted 18 months.  

Also, 91.5% of the participants in the trial were from a white background, so we need more diversity in clinical trials to prove that these drug treatments will work for everyone with early Alzheimer’s disease. 

Is donanemab safe?

As well as testing the effectiveness of donanemab, clinical trials also tested the safety of the drug, by monitoring for bad side effects.

As with all drug treatments, there have been some side effects associated with donanemab.  

These included headaches, reactions to the intravenous drip, and swelling or microbleeds in the brain known to be related to amyloid.

The vast majority of side effects (82.4%) were either mild or were detected in tests but didn’t cause any symptoms.

Data from the main trial and its extension showed that altogether, 15% of participants had a serious side effect. 2.9% of people had a serious side effect related to ARIA, and the remaining 12.9% of people had a serious side effect related to something other than ARIA. 

Unfortunately, there were three deaths in the trial related to the treatment. 

How can I access donanemab?

After reviewing the data and evidence, the MHRA have concluded that donanemab is safe and beneficial to people with early Alzheimer’s disease and will be approved for use in the UK under the brand name Kisunla.  

Donanemab has only been approved for some people with early-stage Alzheimer’s disease, excluding:  

• People with moderate or late-stage Alzheimer’s disease  
• Those with other types of dementia such as dementia with Lewy bodies, vascular dementia or frontotemporal dementia  
• People who carry two copies of the APOE4 gene variant as these individuals are at a greater risk of side effects  

Donanemab may be available from some private health providers.  

To be eligible for donanemab treatment a person would need to be in the early stages of Alzheimer’s disease and have amyloid protein buildup present in their brain. This is shown using amyloid PET scans or testing of spinal fluid.

It is also likely people will need to have a genetic test to learn whether they have the APOE4 variant. 

Will donanemab be available on the NHS?

Whilst the MHRA has approved donanemab, draft guidance from NICE has not recommended it for use on the NHS at this stage.  

The National Institute for Health and Care Excellence (NICE) decide which medicines should be made available on the NHS.  NICE has decided to extend the review of donanemab to consider additional data. A decision final is expected later this year.  

What does this mean for the future and for people affected by dementia?

Research will beat dementia and today’s news about donanemab represents a vital milestone in that journey. It’s important to recognise that donanemab and lecanemab are first generation treatments, and in other conditions we have seen treatments become cheaper, safer and more effective as research continues. We hope to see similar progress in Alzheimer's disease in the months and years ahead.  

In other diseases like cancer, treatments have become more effective, safer and cheaper over time and we hope to see similar progress in dementia. With around 20 Alzheimer’s disease drugs in late-stage clinical trials, more drugs will be submitted for approval within the next few years.

In the meantime, we must not lose sight of the around one million people living with dementia in the UK now. A third of these people don’t have a diagnosis and can’t access the existing dementia treatments and interventions of today, nor confirm if they are eligible for the disease-modifying treatments of tomorrow.

We need to see significant government investment to bring about radical change so that everyone with dementia in the UK can get an early and accurate diagnosis. Without this, people won’t be able to access existing treatments and interventions to help manage their symptoms today or be ready for the disease slowing treatments of tomorrow.

These changes will take time, so healthcare systems must start preparing now to ensure that everyone with dementia can access an early and accurate diagnosis and the treatment and care that should come with it. 

How can you get involved in dementia research?

Alzheimer’s Society is a partner in a service called Join Dementia Research (JDR). The service allows anyone over the age of 18 to register their interest in participating in dementia research; however, researchers are particularly keen to hear from those with a diagnosis of dementia/ or MCI and those that care/support them to register.

If you would like to hear more about this service then please contact our Join Dementia Research helpdesk by calling 0333 150 3456 and asking for the Join Dementia Research helpdesk or emailing us directly at: joindementiaresearch@alzheimers.org.uk.

 We will update this page as new information becomes available. Last updated: 6 March 2025