First of its Kind Therapy for Parkinson’s Disease Advances to Phase 2b Trials

By Daniel Ojeda, Ph.D.

On October 20th, Prothena Corporation plc. and Roche announced they would advance Prasinezumab, a treatment for Parkinson’s Disease, into Phase 2b clinical trials. Prasinezumab is the first antibody-based therapy against alpha-synuclein to reach late-stage development. The announcement comes after it slowed motor function decline by 35% in the PASADENA clinical trial.

Ireland-based Prothena has several investigational therapeutics in the pipeline to treat several devastating neurogenerative and rare peripheral amyloid diseases, including synucleinopathies (such as Parkinson’s disease), Alzheimer’s disease, ALS, frontotemporal dementia, and others.

Alpha-synuclein and Parkinson’s Disease

Parkinson’s Disease (PD) is the second most common neurodegenerative disorder and affects an estimated 7 to 10 million people worldwide. PD is characterized by a loss of neurons that produce dopamine, which the body uses to coordinate movement. As a result, the symptoms of PD include tremors, motor impairments, dementia, and/or psychosis. Currently, there is no cure for PD. The available medications can help mitigate the symptoms, but it does slow the progression of the disease.

The underlying cause of PD is still unknown. However, one of the possible causes is a protein called alpha-synuclein. Under pathological conditions, aggregates of alpha-synuclein are observed and are believed to drive neuronal damage. These aggregates can be transmitted from neuron to neuron, and studies in animal models suggest targeting aberrant alpha-synuclein could be a viable therapeutic strategy.

Apart from Prasinezumab, other therapeutic strategies targeting alpha-synuclein directly or indirectly have been announced over the past couple of years. One of these approaches is developing a vaccine against alpha-synuclein currently in clinical trials created by Affiris, an Austrian biotech company.

PASADENA Clinical Trial

Back in September 2020, during the International Parkinson and Movement Disorder Society’s MDS Virtual Congress, Prothena reported the results of PASADENA, a Phase 2 clinical trial evaluating the safety and efficacy of Prasinezumab. The 52-week long, randomized, double-blind, placebo-controlled, three-arm study enrolled 316 patients. Results demonstrated that Prasinezumab was able to delay the worsening of motor progression by 35% and reduced bradykinesia by 27%.

“Results from the PASADENA study are part of a growing clinical body of evidence suggesting antibodies that optimally target misfolded proteins can result in clinically meaningful benefit. With a growing pipeline of programs based on this scientific approach, Prothena is poised to advance several novel therapeutics for devastating diseases,” said Dr. Gene Kinney, President and Chief Executive Officer of Prothena.

Back in December 2013, Roche and Prothena entered a collaboration to develop antibody therapies targeting neurodegenerative diseases. As part of that agreement, Prothena can earn up to $600 million in milestone payments. After the first patient is dosed as part of the next stage clinical trial, Prothena will earn $60 million, which is on top of the $70 million it has earned to date.

Editor: Rajaneesh K. Gopinath, Ph.D.

Related Article: Exploring RNA Splicing as a Potential New Drug Avenue for Parkinson’s Disease

References

1. https://ir.prothena.com/news-releases/news-release-details/roche-and-prothena-will-advance-prasinezumab-late-stage-clinical
2. https://ir.prothena.com/news-releases/news-release-details/prasinezumab-slows-progression-measures-parkinsons-disease-phase
3. https://www.nhs.uk/conditions/parkinsons-disease/causes/
4. https://www.parkinson.org/Understanding-Parkinsons/Statistics#:~:text=Who%20Has%20Parkinson’s%3F&text=Approximately%2060%2C000%20Americans%20are%20diagnosed,worldwide%20are%20living%20with%20PD.
5. https://parkinsonsnewstoday.com/2020/01/29/fda-response-affiris-phase-2-trial-parkinsons-vaccine-affitope/

Author

Daniel Ojeda