Tom Isaacs, late President and Co-founder of The Cure Parkinson's Trust undergoes infusion of GDNF

For over a decade The Cure Parkinson’s Trust (CPT) has supported the development of research of GDNF (Glial Derived Neurotrophic Factor) as a treatment for Parkinson's. The full results of this pioneering trial are published in Brain and Journal of Parkinson's Disease. 

**The BBC broadcast: 'The Parkinson's Drug Trial: A Miracle Cure?' on 28th February 2019 - following nine participants through their GDNF trial journey, one of whom was CPT's co-founder Tom Isaacs who died unexpectedly in May 2017.


GDNF is a small protein that supports the survival of brain neurons. There are many types of neurotrophic factors in the brain and GDNF is one of these.

Early studies in animal models of Parkinson’s found that GDNF revived dying dopamine neurons (the cells classically affected in Parkinson’s)(1)

Given the results of initial studies with GDNF (and other neurotrophic factors), clinical studies/trials were set up to test if similar effects would be seen in humans, notably a trial(2) led by Professor Steven Gill at Frenchay Hospital, Bristol in 2002. The results of this and other follow-up studies had positive outcomes but overall results of a larger subsequent trial in 2004 were inconsistent with earlier trials, and left questions about the potential of GDNF.

Some experts believed that the different procedures used to pump GDNF into the brain affected the results of certain studies. The Cure Parkinson’s Trust, keen to progress the potential of GDNF for people with Parkinson’s, funded the development of a pioneering 'convection enhanced delivery’ mechanism (CED) to deliver the large GDNF molecule with pin-point accuracy into the mid-brain.

CPT, led by late President and Co-founder Tom Isaacs, supported the development of the recent GDNF trial from the novel pin-point precision delivery mechanism to the recent Bristol study (2017) to test whether GDNF would show any potential benefit as a disease modifying treatment for Parkinson’s.

This trial took place in Bristol under the leadership of Professor Steven Gill and Consultant Neurologist Alan Whone. The Bristol trial participants had the CED mechanism carefully placed into their brains connected to a small port behind the ear. The trial was lengthy and involved three stages:

1) a placebo controlled pilot study of 6 people.
2) a nine-month placebo controlled clinical trial involving 36 people plus the 6 pilot study people.
3) a nine-month open label extension, where all people received GDNF.

Note: By the end of all parts of the study, the placebo group had received GDNF for only nine months, whereas those on GDNF for the first nine months received GDNF for a total of 18 months. Those on the pilot study received GDNF beyond 18 months.

The nine participants GDNF journeys were featured in the BBC documentary: 'The Parkinson's Drug Trial: A Miracle Cure?' including CPT's late co-founder Tom Isaacs.

This innovative trial would not have been possible without the commitment of the incredible participants, and the trial has seen excellent collaboration between the inspirational teams at Southmead Hospital Bristol, MedGenesis, Renishaw, Michael J Fox Foundation, Parkinson's UK and The Cure Parkinson's Trust along with many other generous supporters.

Research Update - 

'Nerve Growth Factors and Parkinson's'



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