Exenatide found to have positive effect on mood

Further analysis of the results from a recent clinical trial of the type 2 diabetes drug exenatide in people with Parkinson's has revealed encouraging signs of a positive effect on mood.

Results from this phase 2 clinical trial of exenatide were published in August 2017. The initial analysis showed positive signs that exenatide may slow the progression of Parkinson's, but the researchers found the treatment had no significant effects on non-motor symptoms and quality of life. 

However, this latest analysis, which focused only on symptoms related to mood, suggests that exenatide may improve mood, apathy and emotional-wellbeing when compared to a placebo treatment.

What is exenatide?

Exenatide has been used since 2005 to treat type 2 diabetes. It works by targeting glucagon-like peptide-1 (GLP-1) receptors in the pancreas, which causes insulin to be released. 

GLP-1 receptors are also found in the brain, and lab-based experiments have suggested that activating them can boost the function of dopamine connections, have anti-inflammatory properties, improve energy production, and switch on cell survival signals.

Previous clinical trials of exenatide have reported promising results. Participants who received the drug in the latest phase 2 clinical trial had improvements in their movement symptoms compared to the placebo group. And this effect remained 12 months after the treatment ended.

The initial analysis of the effects of exenatide looked at its effects on all non-motor aspects of Parkinson's and overall quality of life. As it did not look at particular symptoms individually, these potential effects on mood were not seen. 

The latest analysis highlights improvements in various measures of mood at the end of the 48 week treatment period. However, the effects on mood were no longer present 12 weeks after treatment ended.

Claire Bale, Head of Research Communications and Engagement, comments:

''Further analysis of the results from the most recent trial offers hope that exenatide could help to improve mood and wellbeing for people affected by Parkinson's.

''These findings are very encouraging and now need to be confirmed in larger, longer-term studies.

''This secondary analysis also highlights how important it is that all the potential benefits of new treatments for Parkinson's are fully explored in clinical trials – not just the effects on the typical movement problems. Non-motor aspects are very common in the condition and can have a huge impact on quality of life, so it's vital that they are taken into account when we are assessing the benefits of new treatments.''