Ozempic, used for diabetes, is being tested for slowing Alzheimer’s progression due to its anti-inflammatory effects.
Studies show semaglutide may reduce Alzheimer’s risk by up to 70% in Type 2 diabetes patients.
Experts caution about risks for frail elderly patients, but highlight potential cost benefits of repurposing existing drugs.
Ozempic could help patients with advanced Alzheimer’s disease, scientists believe.
Trials are under way examining the impact of semaglutide – marketed as Ozempic for the treatment of diabetes, and Wegovy for weight loss – in slowing the progression of dementia.
The injections have already been found to protect against a number of diseases, cutting the risk of heart attacks and cancer.
Experts believe the role of the medication in reducing inflammation in the body is key, as this is common to many conditions, including Alzheimer’s and Parkinson’s disease.
International studies tracking 3680 patients with early Alzheimer’s disease will report next year.
However, there is already much excitement because evidence from patients taking Ozempic for Type 2 diabetes suggests a lowered risk of dementia and fewer symptoms among those who do develop Alzheimer’s disease.
One US study of more than one million people with Type 2 diabetes found those put on semaglutide had up to a 70% reduced risk of being diagnosed with Alzheimer’s disease over the next three years.
Type 2 diabetes is already known to increase the risk of dementia, causing metabolic dysfunction in the brain.
At a discussion hosted by Alzheimer’s Disease International, experts said the class of medication, known as GLP-1 agonists, could hold out hope for patients in later stages of the disease.
Jeff Cummings, a professor of brain science and health, said: “Let’s start with the more advanced patients, I think we have to develop drugs for more advanced patients.
“Every patient who has early disease is eventually going on to have late disease, and so we have to find a way of trying to slow that progression into later stage disease. But once they’re there, we have to be able to help them more than we are now.
“But we think drugs like semaglutide, for example, medication that you would take to affect the brain metabolism, or the way the brain works, could have application in later-stage patients, even though, for now, it’s being tested in early-stage patients.”
Cummings, from the Chambers-Grundy Centre for Transformative Neuroscience at the University of Nevada, said drugs that were first developed for mild disease were often later found to work in late-stage disease.
He said: “In donepezil – this is a drug that’s been around for a very long time – it was first developed in mild to moderate Alzheimer’s disease and succeeded, and then it was tested in severe Alzheimer’s disease and succeeded.
“So that’s a common pathway to start with one population. And if it works there, let’s see whether we can treat another part of the population.”
‘Toolkit of treatments’
The potential role of the drugs in combating Alzheimer’s has caused interest, not least because they are significantly cheaper than other drugs.
However, there are particular risks in using GLP treatment in elderly frail populations, particularly those with dementia, given that the drugs reduce appetite, and can cause muscle loss, increasing the danger of falls.
Jacqui Hanley, head of research funding at Alzheimer’s Research UK, said: “It is encouraging to see large studies exploring whether drugs already licensed could be repurposed as a dementia treatment. As these drugs have already been shown to be safe for use, this could potentially speed up the process of testing in clinical trials, as well as being significantly cheaper.
“We know that roughly a third of drugs in clinical trials for Alzheimer’s are treatments used for other conditions. If we are to cure dementia, we must develop a toolkit of treatments that tackle different aspects of the disease and can be used in combination. Research into repurposing drugs may help us do just that.”
The first two drugs to slow the progression of Alzheimer’s have been licensed for use in Britain. However, the National Institute for Health and Care Excellence has refused to fund either lecanemab or donanemab, claiming they do not constitute good value for money.