Results from a one-year, phase 2 clinical trial of the Type 2 diabetes drug lixisenatide suggest that the treatment may slow the progression of motor (or movement) symptoms in Parkinson’s disease.
The LixiPark trial took place in France, led by Professors Olivier Rascol and Wassilios Meissner at the University Hospital of Toulouse and University Hospital of Bordeaux, and involved 156 people with early-stage Parkinson’s across 21 research centres of the French NS-Park network.
It was co-funded by Cure Parkinson’s in the UK, the Van Andel Institute in Michigan, USA, and the French Ministry of Health, with the study’s results published in this month’s New England Journal of Medicine.
In the research trial, which took place over one year, participants were treated with either lixisenatide — a diabetes medicine that helps manage blood sugar levels — or a placebo in addition to their usual Parkinson’s medication. The results of the randomized, double-blinded study showed that the progression of motor symptoms in those receiving the lixisenatide treatment slowed, while motor symptoms in participants receiving the placebo continued to progress.
The difference between the two groups was statistically significant, indicating that lixisenatide may be able to delay the progression of motor symptoms in people with Parkinson’s. The findings were consistent at the end of the 12-month treatment period and two months after treatment stopped.
What is lixisenatide?
Lixisenatide belongs to a group of medicines called GLP-1R agonists approved for the treatment of Type 2 diabetes. Lixisenatide mimics the action of a gut hormone which is released when we eat food, helping the body to make more insulin and slowing down digestion so it takes longer for the body to absorb sugar.
Importantly, the LixiPark trial is actually the second trial using a GLP-1R agonist to slow the progression of Parkinson’s motor symptoms: after a promising Phase 2 trial back in 2017, Cure Parkinson’s are currently finishing a Phase 3 trial of the diabetes drug exenatide in the UK, with results expected this summer. This most recent lixisenatide trial, however, was done on a much larger scale.
There is also a known link between Parkinson’s and Type 2 diabetes, with research suggesting that people with Type 2 diabetes have a higher risk of developing Parkinson’s, and those that do develop Parkinson’s often experience a more rapid progression of their symptoms. Elsewhere, research shows that people with diabetes who are treated with GLP-1R agonists have a reduced risk of developing Parkinson’s.
Next steps
Despite these promising results, there are currently no GLP-1R agonists — lixisenatide included — approved for the treatment of Parkinson’s. Further testing is needed, likely a Phase 3 trial, as well as further study on other GLP-1R agonists, including the outcome of the current Phase 3 exenatide trial.
There may well be a mountain still to climb, but LixiPark trial leaders Wassilios Meissner and Olivier Rascol are hopeful, saying in a joint statement:
“For 30 years, we have been trying to understand how to slow the decline associated with Parkinson’s disease over time. In this context, the positive results of the Lixipark phase 2 trial showing less progression of motor symptoms of Parkinson’s disease over a year constitute a significant step forward in the future management of the disease. We look forward to confirming these encouraging results in the future, in order to translate such findings into clinical practice.”
Find out more about the lixisenatide trial on the Cure Parkinson’s website
