Dementia researchers are leaving no stone unturned in the hunt for new treatments
by Dr Laura Phipps, Science Communications Manager, Alzheimer’s Research UK.
A major goal of dementia research is to find treatments that will benefit the millions of people around the world living with the condition. At this week’s Alzheimer’s Association International Conference we’ve heard results from a number of clinical trials – research studies designed to test whether potential treatments are safe and effective. Diseases like Alzheimer’s are extremely complex, involving multiple biological systems. To tackle these diseases we need to see research into a range of therapeutic approaches, giving us the best chance of finding effective treatments sooner. Here are some examples of how researchers who spoke at this week’s conference are taking up the challenge.
Taking aim at amyloid
Solanezumab isn’t the only anti-amyloid treatment in the development pipeline.
Many potential drugs for Alzheimer’s target amyloid – a hallmark protein of the disease that is thought to cause the nerve cell damage that leads to the symptoms of dementia. On Wednesday we heard about a promising treatment in testing called solanezumab, but this isn’t the only anti-amyloid treatment in the development pipeline.
Adacunamab hit the headlines in March, when researchers announced promising results from an early phase clinical trial. While solanezumab mops up amyloid to stop it doing further damage, adacunamab tags amyloid so it can be cleared by the brain’s immune system. This week, researchers discussed further findings from studies in people with mild Alzheimer’s.
They found that aducanumab reduced amyloid in the brain and slowed down the decline in memory and thinking skills. While the effects were small, this is promising progress and the drug is now entering phase III trials – the final stage of testing in a larger number of people. However, the research team also shared insight into side effects.
When developing any new drug, there is always a careful balance to strike between how effective it is at treating a disease and whether any side effects are too severe to allow patients to continue with the therapy.
With aducanumab, there was leakage of fluid from the blood into the brain, which led to symptoms such as headaches. Before going further, the team needs to investigate the reasons for these side effects and refine the dose.
While these side effects are a disappointment, investigating the underlying biology will yield new insights into the way the drug works. Similar changes occurred in a UK based trial and researchers at the University of Southampton are now working to unravel the reasons for negative side effects.
Boosting chemical messengers
Aducanumab and solanezumab aim to reduce the damage to nerve cells caused by the build-up of amyloid. Current Alzheimer’s treatments, on the other hand, work by reducing the levels of a protein which breaks-down an important chemical messenger in the brain. This results in more of the messenger, allowing nerve cells to communicate more effectively and temporarily helping with symptoms like memory loss.
On Wednesday, we heard from researchers who have developed a drug called RVT-101, which is designed to work alongside these current treatments and, in a different but complimentary way, further increase the levels of the same chemical messenger and provide more benefit to people living with the disease. They showed that people with Alzheimer’s who were given this new drug alongside their existing treatment, had better memory thinking skills and were better able to go about daily activities then people who only received the existing treatment. This drug will now go forward into a phase III clinical trial.
Alleviating behavioural symptoms
Memory loss and thinking difficulties aren’t the only symptoms of dementia. Finding treatments that can alleviate symptoms such as agitation and aggression is also incredibly important, not only for those with dementia but for those around them.
In the past, anti-psychotic drugs were used more widely to deal with such symptoms, however work in 2009 supported by Alzheimer’s Research UK revealed the risks of long-term use of these drugs. We heard from researchers who are trying to find alternative approaches to improve these behavioural symptoms of dementia using both drug and non-drug approaches. One team reported findings using a combination of two compounds – one an active ingredient in cough medicines and the second used to treat irregular heartbeat.
This combination, known as AVP-923, is currently used to treat episodes of uncontrollable crying or laughing that result from a number of brain conditions. However, this new 10-week study in people with Alzheimer’s disease, set out to control aggression and agitation. The team found that those taking AVP-923 showed fewer behavioural symptoms than those on placebo. The researchers will now trial this combination in a larger and longer study.
We have recently funded a trial at the University of Cambridge, testing the ‘happy hormone’ Oxytocin in people with frontotemporal dementia. Oxytocin has been linked to social bonding and feelings of empathy. The Cambridge-based team wants to find out whether the hormone can help increase empathy and social awareness in people with FTD, helping them with their behavioural symptoms.
When we hear the term ‘clinical trials’ most people think of tests of new drugs. However, clinical trials can also be used to test other interventions such as lifestyle changes, talking therapies, and training schemes. Yesterday we heard from researchers who are using clinical trials to explore whether exercise could help people with dementia.
While we have known for some time that exercise can reduce the risk of developing dementia, yesterday’s findings suggested that regular aerobic exercise could also help people who have already developed memory and thinking problems. Researchers presented evidence indicating that regular exercise may:
- Alleviate symptoms like depression and anxiety in people with Alzheimer’s
- Be associated with reduced levels of the hallmark Alzheimer’s protein tau in people with mild memory and thinking problems
- Improve memory and thinking in people who had some blood vessel damage in the brain.
All of these potential treatments are promising but need to be tested further before we can say for sure that they will benefit people with Alzheimer’s or other forms of dementia. Clinical trials can’t take place without your help – researchers need 1000’s of volunteers to help develop these treatments. If you’d like to learn more about taking part in research and sign-up to take part, visit Join Dementia Research or call our Dementia Research Infoline on 0300 111 5 111.