Brain cells under a microscope

Update on GDNF trial: analysis underway


The groundbreaking GDNF trial is nearing completion and in-depth analysis of the data is underway.

Initial data, released on 7 July 2016, suggests the treatment is safe but that there was no significant difference between participants who received GDNF compared to those who received a placebo (dummy) drug.

These initial findings appear disappointing but the full results and analysis may yet reveal positive insights.

What is GDNF?

GDNF (or glial cell line-derived neurotrophic factor) is a special protein that is naturally produced inside the brain and supports the survival of many types of brain cells – including the cells lost in Parkinson's.

We will be working to share the results of the trial as quickly as we can
Dr Alan Whone, Principal Investigator in the GDNF study

In total, 41 people with Parkinson's are taking part in the clinical trial in Bristol which is divided into two phases.

The first phase was a 9-month double blind trial. 35 participants received either GDNF or a placebo drug and neither researchers nor participants knew which one they were getting at the time.

Now this phase is complete, researchers can measure the difference the drug makes to Parkinson's. The second phase, where all participants receive GDNF, is currently underway.

The trial aims to establish whether treatment with GDNF has the potential to slow, stop or reverse the course of the condition.

When and how will results be announced?

Dr Alan Whone, Principal Investigator for the study commented:

"It's important to stress that there is a huge amount of careful analysis required to understand the results of this extremely complex clinical trial.

"This further analysis will be our focus for the next few months and could reveal positive insights despite the topline negative result.

"In addition, all participants are currently in a longer term extension study which may reveal that it takes longer than 9 months to see the benefits of GDNF.

"We will be working to share the results of the trial as quickly as we can."

How can I keep up to date?

Dr Arthur Roach, Director of Research at Parkinson's UK said,

"The GDNF trial is one of the most important studies ever funded by Parkinson's UK, with support from The Cure Parkinson's Trust, and we're delighted that the results are coming soon.

"We'll be working closely with the research team to ensure that when the full results are published we can provide in-depth information as soon as possible."