The clinical trial, which enrolled 41 patients with Parkinson’s Disease, was funded by Parkinson’s UK with support from The Cure Parkinson’s Trust and in association with the North Bristol NHS Trust.
The investigational treatment was directly delivered into the brains of the enrolled 41 patients with Parkinson’s Disease. It was carried out using a convection enhanced delivery system (CED), which has a novel delivery mechanism, to administer a neurotrophic factor to the putamen, a region located deep inside the brain called the putamen.
Cure Parkinson’s Trust said that although the trial could not meet its primary end point, it has yielded some very interesting findings in the data. The brain imaging data from the trial indicates that GDNF was having an interesting effect in the brain which makes a case for further investigation.
GDNF trial principal investigator Alan Whone said: “The spatial and relative magnitude of the improvement in the brain scans is beyond anything seen previously in trials of surgically delivered growth-factor treatments for Parkinson’s. This represents some of the most compelling evidence yet that we may have a means to possibly reawaken and restore the dopamine brain cells that are gradually destroyed in Parkinson’s.”
The 41 participants in the Parkinson’s Disease trial went through robot-assisted surgery to have four tubes inserted into their brains through which GDNF was infused directly into the putamen.
The Cure Parkinson’s Trust said that by the end of the trial, most of the patients had meaningful clinical improvement although the evidence was considered to be inconclusive as the trial in its final stages was not a double blinded one without comparison group.
Furthermore, a number of patients felt that the treatment had beneficial effects. The study team reckons that further investigation of GDNF is needed to explore increased dose and delivery of the therapy over a longer period of time.
The Cure Parkinson’s Trust deputy CEO Helen Matthews said: “These results, particularly the brain scans show that GDNF, delivered with Convection Enhanced Delivery, has promise as a potential treatment to slow, stop or even reverse Parkinson’s.
“However, it is critical we now concentrate on how to best support moving GDNF forward, to understand if it can be a viable treatment to potentially regenerate dopamine cells and impact the lives of people living with Parkinson’s.”