Study Reveals Limited Efficacy of GLP-1 Drug in Parkinson's Treatment

A recent clinical trial has found that exenatide, a GLP-1 drug, offers little to no benefit for individuals suffering from Parkinson's disease. This research, conducted by a team from University College London and published in The Lancet, aimed to assess whether exenatide could positively influence movement, symptoms, or brain imaging in these patients.

The study represents the largest and longest investigation of exenatide's effects on Parkinson's disease to date. Conducted over 96 weeks, it involved 194 participants from six research hospitals across the UK, including major cities such as London, Oxford, and Edinburgh. Participants were randomly assigned to receive either weekly exenatide injections or a placebo, with neither the participants nor the researchers knowing who received which treatment.

Upon completion of the trial, researchers reported no significant advantages for those receiving exenatide compared to the placebo group. Evaluations of patient movements, self-reported symptom severity, and imaging studies yielded no discernible benefits from the medication.

Professor Thomas Foltynie, the lead author of the study, acknowledged the disappointment that these findings would bring to patients and the broader research community focused on Parkinson's disease. The anticipation surrounding the trial's results stemmed from previous smaller studies that had suggested potential benefits of exenatide for Parkinson's patients.

GLP-1 drugs, including exenatide and newer agents like semaglutide (Wegovy and Ozempic), have gained popularity for their potential health benefits, including weight loss and management of type 2 diabetes. Unlike newer drugs, exenatide and others in its class have shown the ability to cross the blood-brain barrier, leading to earlier studies that suggested they might offer therapeutic benefits for neurological conditions.

Despite the negative results, Professor Foltynie noted that it is still unclear whether a specific subgroup of Parkinson's patients might benefit from exenatide. The research team plans to further analyze the data to determine if certain factors, such as abnormal blood test results indicating 'pre-diabetes,' might predict a better response to the medication. They also aim to investigate whether these factors were more prevalent in earlier studies that reported positive outcomes.

The trial was conducted at the UCL Queen Square Institute of Neurology and the UCLH National Hospital for Neurology and Neurosurgery. The high retention rate of participants and confirmed compliance with the medication through blood tests adds credibility to the results of this comprehensive trial.

For more detailed information, refer to the full study published in The Lancet.