Researchers from the University College London have successfully shown better movement test results by patients with Parkinson’s when treated with an approved diabetes drug as compared to patients who received a placebo. The benefit persisted even when the drug had not been taken for 12 weeks, suggesting it might be helping to slow the progression of the disease.
Parkinson’s disease is a progressive neurological condition affecting the central nervous system. There is currently no cure for the condition, but now research has found one drug could cause dramatic improvements to patients.
“This is a very promising finding, as the drug holds potential to affect the course of the disease itself, and not merely the symptoms,” said senior study author Tom Foltynie, from University College London’s Institute of Neurology.
“With existing treatments, we can relieve most of the symptoms [of Parkinson’s] for some years, but the disease continues to worsen,” he said in a university news release. “This is the strongest evidence we have so far that a drug could do more than provide symptom relief for Parkinson’s disease.”
In the study, 60 people with Parkinson’s received either a weekly injection of exenatide or an inactive placebo for 48 weeks, along with their regular
medications. Exenatide, derived from Gila monster saliva, is a glucagon-like peptide-1 (GLP-1) agonist. It treats Type 2 diabetes by mimicking the hormone GLP-1, which triggers insulin secretion.At the end of that period, those who took the diabetes drug scored four points higher on a 132-point scale of agility, speech and tremors than those who took the placebo.
However, the study did not determine conclusively whether the drug modified the disease itself, a question which the team intends to answer through further research.
The UCL team is looking to pinpoint just how exenatide works in Parkinson’s, where the loss of dopamine-producing brain cells leads to motor symptoms, such as impaired coordination and muscle stiffness. Previous research has shown that exenatide boosts motor function in animals and that stimulating GLP receptors in the brain can improve dopamine connections.
“While we are optimistic about the results of our trial, there is more investigation to be done, and it will be a number of years before a new treatment could be approved and ready for use. We also hope to learn why exenatide appears to work better for some patients than for others,” said the study’s first author, Dilan Athauda, MRCP, a clinical researcher at UCL.
“I think it is a really exciting step forward,” said Dr Heather Mortiboys, an expert in neurodegenerative diseases at the University of Sheffield, pointing out that the use of repurposed drugs could expedite treatment compared with developing treatments from scratch.
David Dexter, deputy director of research at Parkinson’s UK, said the study was encouraging. “The small benefits seen in this study are particularly promising because only a low level of the drug injected actually reached the brain,” he said. “This suggests that finding treatments that work in a similar way, but are better able to cross from the bloodstream into the brain, may be even more effective.’
