A drug commonly used for treating diabetes may reverse symptoms of late-stage Alzheimer's disease and is now in the process of entering a major clinical trial.

Researchers from Lancaster University in the UK conducted a study revealing that the drug, liraglutide, may reverse memory loss in the late stages of Alzheimer's, as well as prevent the build-up of toxic plaques on the brain that contribute to symptoms of the disorder.

Liraglutide is from a class of drugs known as GLP-1 (Glucagon-like peptide-1) analogue. The drug is prescribed to those suffering from diabetes and is used to stimulate insulin production.

But the study, published in the journal Neuropharmacology, shows that the drug can also pass through the blood-brain barrier and protect brain cells.

The researchers tested the drug on the brains of 14 month-old mice who were suffering from late stage Alzheimer's disease. Liraglutide was injected into the mice over a 2-month period.

Significant improvement in mouse model

During this period, the mice demonstrated a significantly better performance on object recognition tests, and their brains showed a 30% reduction in the build-up of toxic plaques.

Professor Christian Hölscher, of the University of Lancaster and lead study author, told Medical News Today exactly how the drugs work:

"Liraglutide activates receptors on neurons that set a growth-factor type of signaling cascade in motion.

This means that the cell repair of neurons is improved, the energy metabolism is normalized, and synapses are kept functional. Oxidative stress is reduced, and growth and replacement of neurons is improved. The brain is much better placed to cope with stress and toxic influences."

Prof. Hölscher said that their findings from the mouse model showed that the key biomarkers of the disease, such as aggregation of beta-amyloid to form plaques in the brain, memory impairments, loss of synapses, loss of synaptic activity, and the development of a chronic inflammation response in the brain were much reduced.

"This is most encouraging. If similar effects are found in patients with Alzheimer's disease, we should see clear improvements," he added.

Drug could be a 'landmark discovery'

The first clinical trial of Liraglutide in patients with Alzheimer's disease, partly funded by the Alzheimer's Society as a part of its Drug Discovery program, is underway.

Dr. Paul Edison of Imperial College London will lead the trial, and he will begin recruiting patients over the next few weeks.

"It will test how they will progress when compared to a control group that receives a placebo. This will give us the first impression of how effective it is in humans," Prof. Hölscher explained.

"The trial measures neuronal activity in the brains of Alzheimer's patients and can give us a good idea of how good it is in protecting the brain from neurodegeneration."

Dr. Doug Brown, director of research and development at the Alzheimer's society, commented that their focus on repurposing existing drugs as dementia treatments is an exciting way of bringing new treatments closer.

"This exciting study suggests that one of these drugs can reverse the biological causes of Alzheimer's even in the late stages and demonstrates we're on the right track," he added.

Prof. Hölscher told Medical News Today that if this drug shows the same protection of neurons in the brain that it shows in mouse models of Alzheimer's, then they will have created the first treatment for patients that protects neuronal function and activity, memory, and synaptic numbers, while reducing amyloid plaques and the inflammation response in the brain.

He continued:

"This would be a landmark discovery. People would be able to continue to lead an independent life, perhaps even continue to work. Let's hope that we will see a robust improvement in this trial."

Medical News Today recently reported that people living in wealthier countries may be at higher risk of developing Alzheimer's due to significantly reduced contact with bacteria and viruses.