Highlights from the World Parkinson Congress - Emerging Therapies

At the moment, there are 162 Parkinson’s clinical trials taking place worldwide. These are testing both new and repurposed drugs for Parkinson’s, towards the ultimate aim of finding new ways to slow or even stop the progression of Parkinson’s.

To complete these 162 trials, we’ll need around 17,000 people in total to take part. We need people with different symptoms, genetics and experiences, to come forward and take part. Without people taking part, it would simply be impossible to know whether these new potential treatments are effective and safe for use in treating Parkinson’s. Read about how you can play an essential part in the research process.

The Emerging Therapies session covered a number of avenues being investigated towards new treatments for Parkinson’s. In this blog, we bring you some of the latest updates about emerging new therapies for Parkinson’s, alongside the views of research volunteer Joe Gregory, who attended the session.

Repurposing drugs

We know that finding new drug treatments can take a long time. The process between discovering a potential new drug and getting it approved for use is lengthy and involves many steps. While frustrating, these steps are necessary to ensure that any new treatments are safe and effective for the people taking them.

You can read more about the drug approval process in our research magazine, Progress, on page 4 [PDF, 5.7MB].

But there are some ways that this process can be sped up. One of these is looking at repurposing existing drugs. This means taking a drug that is already used by people to treat one condition or symptom, and seeing if it can be used to treat something else.

Repurposing a drug can help speed up the research process as it’s already known to be safe for people to use. This means that some of the lengthy testing and approval processes can be cut down, as long as the drug is proven to be effective.

Dr Lorraine Kalia from the University of Toronto discussed why Parkinson’s researchers are looking at repurposing drugs. Of the 162 ongoing clinical studies, 52 are looking at repurposed drugs. One example of this is ambroxol, a component of a cough medicine. Research has shown that ambroxol might be able to boost levels of an enzyme called GCase. In brain cells, GCase helps clear away waste products and prevent them building up. 

Often in people with Parkinson’s, the brain cells can’t clear away waste properly, and this can lead to damage and death of the cells. It’s thought that ambroxol may help improve the body’s ability to clear away these clumps of waste and prevent damage.

Read more about ambroxol.

Drugs and genetics

The role of genes in Parkinson’s has been widely discussed, including at the WPC.

Around 10 to 15% of people with Parkinson’s have a mutation, or a change, in one of the genes that has been linked to Parkinson’s. But even in people who don’t have a specific change in one of these genes, the gene can sometimes still work differently compared to someone without Parkinson’s. This has led researchers to look at using drugs that can change the way these genes work.

Dr Jesse Cedarbaum from the Yale School of Medicine spoke about 2 genes that are currently the target of new emerging therapies:

SNCA1

This gene provides the instructions for making a protein called alpha-synuclein. In Parkinson’s, misformed alpha-synuclein can start to clump together and cause damage to the cells. An avenue of research is looking at finding ways to stop this happening, by sticking a drug or a protein to the ends of the alpha-synuclein protein and preventing it from clumping up.

There are a number of new therapies being tested that aim to do this, including a vaccine. Vaxxinity recently shared that an early trial of vaccine UB-312 was safe, but we need more research to understand whether it might be able to prevent clumps of alpha-synuclein.

Read more about UB-312 on the Vaxxinity website.

LRRK2

In some people with Parkinson’s, the LRRK2 gene becomes hyperactive and starts causing disruption to the normal working of the cell. So researchers are looking at ways to try and reduce its activity.

One drug being investigated for this is DNL151. This drug has already passed an initial phase of safety testing, and we look forward to hearing about a new, phase 2 trial to understand more about how this might provide a benefit for people with Parkinson’s.

Immune therapies

The immune system is the body’s natural defence mechanism, protecting us against infection from bacteria, viruses and much more. But for some people, the immune system becomes too active and starts attacking healthy cells in the body. In this case, it might be necessary for the individual to take an immunosuppressant, a drug which reduces their immune response.

Researchers spotted that people who had been prescribed immunosuppressants were less likely to develop Parkinson’s. And, looking at brain scans of people with Parkinson’s, they could see that some people had an excess of inflammation in some of their brain cells. This led researchers to study whether some anti-inflammatory drugs might also be useful for people with Parkinson’s.

Dr Caroline Williams-Gray from the University of Cambridge shared some of her research which is looking at using an anti-inflammatory drug called azathioprine for people with Parkinson’s. Azathioprine works to reduce the number of immune cells being produced in the body. This in turn can prevent an overload of immune cells in the brain. The AZA-PD trial is looking to see whether azathioprine can reduce the inflammation in the brain, but also slow progression of Parkinson’s. The team has completed recruitment for the study, and we look forward to the results.

Read more about the AZA-PD trial on the Cambridge Clinical Trials Unit website.

Joe’s perspective

Joe Gregory was diagnosed with Parkinson’s in 2019 and was attending his first World Parkinson Congress in Barcelona.

"I attended the ‘Emerging Therapies’ presentation and found the topics very interesting and enlightening.

"I was surprised to learn from Dr Lorraine Kalia’s that the process of developing any new drug treatment usually takes about 13 to 15 years. And that even this lengthy time may not lead to the drug being approved for use. Repurposing existing drugs can really speed up the process, and prove to be so much cheaper in research costs.

"I was interested to hear about the repurposing of amantadine. This was a drug initially used in the 1960s to treat influenza (‘flu’). But further research uncovered a new role for amantadine, and by the 1990s it was being used to treat levodopa-induced dyskinesia issues. I thought it was a great example of how useful repurposing into something it was not initially intended for could be.

"Dr Cedarbaum’s presentation, focusing on the development of different drugs for different gene targets, was quite technical although I absolutely understood the main principles. I had indeed taken part in Parkinson’s genetic research myself a few months ago, and learned that I was passed a mutant gene by one of my parents. I remain interested to learn more about the role of genetics in Parkinson’s, particularly being a parent, and now a grandparent.

"I felt that all of these presentations on Emerging Therapies were very interesting and very useful for researchers, Parkinson’s professionals, and those living with the condition."

Looking forward

This is an exciting time for Parkinson’s research, with more phase 3 trials going on worldwide than ever before. And particularly, more studies looking at ways to slow or stop progression of Parkinson’s. Stay up to date with the latest research by joining our Research Support Network.