From 2013-16 a group of 42 people with Parkinson’s were recruited on to an innovative & ground breaking clinical trial in Bristol, England.

The GDNF trial showed remarkable improvements in participants’ brain scans, but failed to meet the required end points and the trial ceased.

The GDNF Participant Group was formed when the trial ended – the volunteers from the trial were determined that the efficacy of GDNF should be further investigated and given another opportunity based on their personal experiences of improved symptoms.

This website charts the GDNF Participants’ Journey through the years since and their determination to have this particular Neurotrophic factor revisited scientifically.

We are now raising awareness and funds for further investigation into GDNF and other neurotrophic factors, that are also showing real promise.

We invite you to explore our website, read our stories, and form your own opinion.

GDNF Participant Group - Logo

The GDNF Participant Unifying Challenge

In support of Neurotrophic Factors 4,200 miles to walk, run or cycle – an amazing 7,683 miles completed! For a gallery of participants click here 🙂

During the first half of September 2021 teams across the UK will run, walk, ride, and probably crawl the 4,200 miles representing the 42 participants of the original GDNF trial.

Many of the 42 individuals who participated in the Bristol GDNF clinical trial will undertake a unifying challenge in 2021 to highlight and support the future of neurotrophic factor therapies.

Each team will include participants themselves, their families, their friends and other supporters who, like the participants, believe in the future of neurotrophic factors.

The Challenge will bring people and organisations together, to raise awareness of and urgency for the need for a cure and put people affected by Parkinson’s truly at the centre of trial design.

The Challenge will also raise funds to progress research and trials into the beneficial effects of neurotrophic factors, increasingly seen by science as having the potential for a cure.

There’s still a few final figures to come in but the total is way over the challenge we set at 7,683 miles.

Read the press release

What can you do?

1. Join our Challenge

Join an existing team or form one of your own. View the map & find your local team. Find us on location & join us for some exercise. Use social media to help spread the word. Contact us if you would like more information or wish to take part.

2. Make a donation

Make a donation to individual teams or a global donation to Virgin Money, supporting Funding Neuro, Parkinson’s UK or Cure Parkinson’s. These charities have committed to further research into Neurotrophic Factors as potential solutions for Parkinson’s.

3. Sign our Petition

Urgency is required if we are to provide a cure for Parkinson’s. We are asking the government to invest more in order to save money and lives in the longer term. Their budget towards research is shrinking and was down again last year and yet the figures for people being diagnosed are increasing rapidly. It is time to galvanise our community and combine our voices so we can be heard.

4. Become a PD Avenger

We are a global alliance of people with Parkinson’s, our partners and friends, standing together demanding change in how the disease is seen and treated.

We add urgency to research, wellness and advocacy by uniting people and organizations to the cause of ending Parkinson’s.

The Parkinson’s Drug Trial: A Miracle Cure?

Filmed over six years, 42 people with Parkinson’s take part in a groundbreaking medical trial. Can the results give hope to 10 million Parkinson’s sufferers worldwide?

This is our story, hopefully you’ve seen it, it’s not currently available on the BBC iPlayer but there are some clips available on the iPlayer and other clips on YouTube.

We found the results truly life changing.

Have a look through the clips and see the story for yourself. Hopefully it will help you understand why we’re so excited, why we’re working so hard, why we’re willing to push so far to get this drug and delivery system back into a treatment and even a cure for Parkinson’s.

Read more about the documentary here.

Darren and Jayne Calder - Founder of Raise a Million for GDNF
“It changed my life… then they took it away”

I am Darren Calder and I have Parkinson’s.

Diagnosed back in 2005, they say life begins at 40…. it was certainly the start of a whole new meaning of life for me.

In 2013 I took hold of the reins to guide my destiny and became a participant of a drug trial, documented on the BBC 2 show ‘The Parkinson’s Drug Trial: A Miracle Cure?’

GDNF is a protein which was under clinical trial for the treatment of Parkinson’s. Following the ground-breaking Phase 2 trial, I am raising funds for further investigation into this promising treatment which could lead to the next Phase trial.

I have developed this website to help keep the GDNF story alive because I have complete belief in its efficacy, to convey the importance of taking part in clinical drugs trials and to raise the profiles of those incredible people who are proud to say we are “The GDNF Believers”.

Read more of Darren’s story here…

Darren Calder and his support team, friends, and family

This is a picture of me with my family and friends, all fantastic supporters of my cause, words can’t express my appreciation and my good fortune of having such a loving group around me.

Darren Signature

Help us reach our goal, help us find a cure.

We are holding events throughout the year to reach a combined target of £1 Million, raised by the participants of the Phase 2 study. There are three charities actively involved whose work stands out and our aim is to support their efforts by raising the profile of neurotrophic factors, and fundraising on their behalf.

The Cure Parkinson’s Trust (CPT) has one goal – to cure Parkinson’s. CPT funds innovative and promising research which is dedicated to finding new treatments that can slow, stop or reverse Parkinson’s.

New technology that we support allows drugs to get to where they need to be in the brain. With it we are able to bring hope for the first time to sufferers of serious conditions like Parkinson’s or brain tumours. With your help we can pioneer new treatments and accelerate cures.

We are Parkinson’s UK. Powered by people. Funded by you. Improving life for everyone affected by Parkinson’s. Together we’ll find a cure.

Latest News


GDNF! What Happened To Me by Andy Rollin

Andy was diagnosed with Parkinson’s at the age of 47, but surely that is something that old people get? 5 years later he had a once in a lifetime chance to participate in ground breaking clinical trial to see if something called GDNF could slow, stop or reverse his Parkinson’s.

Read more…

Ending Parkinson’s Disease Book

A Prescription for Action by Ray Dorsey, Todd Sherer, Michael S. Okun, Bastiaan Bloem. The authors of this book have proposed a bold PACT to Prevent the disease, Advocate for Policies, Care for Patients and Treat the condition.

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Grierson British Documentary Award goes to “The Parkinson’s Drug Trial: A Miracle Cure?”

Absolutely thrilled to announce that “the Parkinsons Drug Trial – A Miracle Cure?” won at the Grierson British Documentary Awards under the heading of Best Science Documentary.

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