Dementia researchers are leaving no stone unturned in the hunt for new treatments
July saw a hum of excitement in the mainstream media over the promise held out by Solanezumab in the treatment of dementia. Blogging for Alzheimer’s Research UK, Dr Laura Phipps from Science News outlines the other avenues of study in the battle against dementia. 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 last month’s Alzheimer’s Association International Conference delegates heard results from a number of clinical trials, covering a range of therapeutic approaches. Here are some examples of how researchers who spoke at the conference are taking up the challenge.
Many potential drugs for Alzheimer’s target amyloid – the hallmark protein of the disease that is thought to cause the nerve cell damage that leads to the symptoms of dementia. Whereas delegates heard about the promising treatment in testing solanezumab, this isn’t the only anti-amyloid treatment in the development pipeline.
Adacanumab 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, adacanumab tags amyloid so it can be cleared by the brain’s immune system. At the conference, 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.
There was leakage of fluid from the blood into the brain, which led to symptoms such as headaches. The team will be investigating these side effects with a view to refining the dose.
While the 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 undermines the effective working of neurons in the brain.
The conference featured researchers who have developed a drug called RVT-101, which is designed to work alongside these current treatments and, in a different but complementary way, further increasing the effectiveness of the neurons. 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 than people who only received the existing treatment. This drug will now go forward into a phase III clinical trial.
Alleviating behavioural symptoms
Finding treatments that can alleviate AD symptoms such as agitation and aggression is 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. Researchers are trying to find alternative approaches to alleviate 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.
Alzheimers Research UK recently funded a trial at the University of Cambridge, testing the Oxytocin in people with frontotemporal dementia. 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.
The conference also included 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, findings suggest 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; and improve memory and thinking in people who had some blood vessel damage in the brain.
To refer volunteers to studies into dementia, visit Join Dementia Research or call the Dementia Research Infoline on 0300 111 5 111.
Adapted for the BGS Newsletter and re-published with the kind permission of Alzheimer’s Research UK