Dementia Support Line
Researching new drugs for Alzheimer’s disease
For the first time, drugs that slow down memory and thinking decline in early Alzheimer’s disease have been approved by UK regulators. But research never stops. Here we explore the next wave of promising new drugs.
What drugs are there for people living with Alzheimer's disease?
Alzheimer’s disease causes the cells in the brain to get sick and eventually die, which leads to symptoms like memory loss.
Donepezil, memantine, rivastigmine and galantamine have long been used to manage symptoms of Alzheimer’s disease, Lewy body dementia, Parkinson's disease dementia, and mixed dementias.
However, these drugs do not slow down the progression of the disease. Recent clinical trials have shown this is possible with a class of drugs called ‘disease-modifying' treatments.
Two disease-modifying treatments have been approved for use in the UK, these are donanemab, and lecanemab. However, they are not available on the NHS.
Promising new Alzheimer’s drugs
There are also a number of breakthrough drugs which have recently finished or are coming to the end of their clinical trial. Click on the link to jump to content on each new Alzheimer's drug:
Semaglutide
Remternetug
Hydromethylthionine mesylate (HMTM)
Blarcamesine
Clinical trials for Alzheimer’s disease
Before a drug can be approved for use in the UK, or another country, it must be shown to be safe and effective. To do this, drug companies run rounds (or phases) of clinical trials to show how well a drug works and how safe it is.
Phase 1: This initial phase involves a small group of volunteers and aims to assess the drug's safety and appropriate dosage.
Phase 2: A larger group of participants, usually numbering in the hundreds, are involved in Phase 2 trials. This phase focuses on evaluating the drug's effectiveness, whilst continuing to monitor safety.
Phase 3: These large-scale trials often include hundreds or thousands of participants and are designed to confirm the drug's efficacy and safety in a diverse population.
If the Phase 3 trials are successful, the results are passed onto regulators, like the MHRA, who decide whether the drug should be approved for use.
The new drugs for Alzheimer’s disease listed below have recently finished or are coming to the end of the Phase 3 trials.
What is semaglutide?
Semaglutide is a medication primarily known for its use in managing type 2 diabetes and more recently, aiding in weight loss. It is made by Novo Nordisk and sold as a pill and marketed under the brand names Ozempic and Wegovy. Research into people taking drugs like semaglutide for diabetes showed that they had a reduced risk of developing dementia. This led to clinical trials to test the potential role of semaglutide in helping to treat Alzheimer's disease.
Semaglutide works by mimicking a natural hormone in the body that stimulates insulin production and reduces blood sugar levels. Scientists believe that this mechanism might also be beneficial for the brain. By improving insulin sensitivity and potentially interacting with receptors involved in learning and brain cell protection, semaglutide could potentially slow the progression of Alzheimer's disease.
What is remternetug?
Remternetug is a new drug from Eli Lilly, who also make donanemab. Like lecanemab and donanemab, remternetug is an immunotherapy drug that targets amyloid. It is also for people living with early-stage Alzheimer’s disease and has been described as a second-generation immunotherapy as it targets the same type of amyloid as donanemab but is hoped to perform better.
After initial safety tests, Eli Lilly began a larger-scale phase 3 trial of remternetug (called TRAILRUNNER-ALZ 1). This was set up to test the effectiveness and safety of remternetug in a larger group of people with mild Alzheimer’s disease. The trial is also comparing an injectable version of the drug with the intravenous drip method. This may provide a more practical way of taking the drug – that is similar to insulin pens used for diabetes.
This trial has finished collecting the data for its primary endpoint (the percentage of patients who had amyloid cleared), and the full trial is due to end in 2025.
Eli Lilly has also begun testing remternetug in two new trials – exploring its safety and effectiveness in early Alzheimer’s disease, and in people with Alzheimer’s disease-causing mutations.
What is hydromethylthionine mesylate (HMTM)?
Hydromethylthionine mesylate (HMTM) is a drug developed by TauRX, which is taken orally. It targets a protein called tau which builds up in the brains of people with Alzheimer’s disease.
The main trial, of HMTM didn’t show any difference from placebo in its effect on memory and thinking decline in people with Alzheimer’s disease. TauRX suggested that this may have been due to the unexpected effect of the placebo drug.
What is blarcamesine?
Blarcamensine is a drug made by a company called Anavex Life Sciences. Blarcamesine works by targeting brain receptors that help memory, learning, and protecting brain cells from damage in Alzheimer’s disease. Based on preclinical studies it may also promote nerve cell survival and prevent the formation of tau clumps.
Blarcamesine is being investigated for Alzheimer's disease, Parkinson’s disease and other brain disorders related to development.
Can these drugs be accessed in the UK now?
At this stage, only lecanemab and donanemab are available to patients in the UK outside of clinical trials. These two amyloid-targeting drugs have been approved for use in the UK but have not been recommended for use through the NHS and so are only available to people paying to access them privately.
Before other drugs also become available in the UK, their associated pharmaceutical companies must apply to the Medicines and Healthcare Products Regulatory Agency (MHRA) for approval. The MHRA will decide whether to approve these drugs and make them available for use. These decisions will consider both the safety and the effectiveness of each drug.
Could a new Alzheimer's disease drug become available on the NHS?
For a drug to be available on the NHS, it needs to be recommended by the National Institute for Health and Care Excellence (NICE). For this decision, NICE will consider how cost-effective a treatment is. We are waiting for final decisions from NICE about whether lecanemab and donanemab will be recommended for use on the NHS. However, draft guidance did not recommend these drugs as they did not meet the threshold required to be considered cost-effective.
Many different brain diseases cause dementia, with each disease affecting brain cells in different ways. Research must continue to uncover what is going wrong inside the brain. With this knowledge, researchers will develop new, innovative treatments to tackle every type of dementia.
Alzheimer’s Society is committed to continuing to invest in the best researchers who will go on to develop improved, targeted treatments that will someday benefit everyone living with dementia.
Recently lecanemab, marketed under the trade name Leqembi, was the first disease-modifying treatment approved for use in the UK for early Alzheimer’s disease. We are currently waiting for the final recommendation from NICE for lecanemab, though the draft recommendation is that it will not be made available on the NHS.
Lecanemab targets a protein called amyloid that builds up in the brains of people with Alzheimer’s disease. It is an immunotherapy, which means it uses the immune system of the brain to remove the amyloid protein. This has been shown to slow down the decline in memory and thinking skills of people with early Alzheimer’s disease.
Lecanemab is currently offered as an intravenous infusion – through a drip bag. However, an under-the-skin injectable version is being tested and has been approved for use in the US. It is not clear yet if the drug company will apply for this version to become available in the UK.
Read more about lecanemab here.
Donanemab (marketed as Kisunla), has also been approved for use in the UK.
It works in a similar way to lecanemab. We are also waiting to hear if donanemab will be made available on the NHS, through the draft recommendation suggests that that it also will not be.
Read more about donanemab here.