There are diverse development strategies and trends in Parkinson’s disease (PD) treatment at present, however, only a few of them address the pressing need for a disease-modifying therapy (DMT). This reflects the various complexities in the process of understanding the exact pathophysiology of the disease through bringing new therapies into this market. Therefore, if any DMT managed to enter the PD market, it would revolutionise the treatment paradigm and generate a strong uptake, says GlobalData.

Sarah Elsayed, Neurology Analyst at GlobalData, comments, “There is currently no cure for PD, despite being the second most common chronic progressive neurodegenerative disorder in the elderly after Alzheimer’s disease. However, treatments are available to help reduce the main symptoms and maintain quality of life for as long as possible. The current symptomatic landscape centres on the management of dopamine levels in the brain, with levodopa-based therapies remaining the standard of care in the PD market for the past half-century, as they have a relatively low cost, and they are effective in relieving motor symptoms.”

The need for DMTs is one of the highest unmet needs. Different companies within the late-stage PD pipeline are developing several drugs that target PD with novel mechanisms of action (MOAs). The hope remains that these companies will uncover a class of drugs that works effectively to slow or halt the disease course.

Elsayed continues, “The late-stage pipeline reflects two main approaches that are looking to address the need for DMTs. Firstly, Roche/Prothena’s PRX-002 (prasinezumab), a monoclonal antibody (mAb) targeting the α-synuclein protein, preventing their aggregation and potentially halting disease progression. PRX-002 is advancing into a global Phase IIb trial called PADOVA, which is planned to start in H2 2021. Secondly, Novo Nordisk’s Victoza (liraglutide), which is an anti-diabetic drug that is repurposed for potentially treating idiopathic PD. It belongs to glucagon-like peptide-1 (GLP-1) receptor agonists, which have demonstrated neuroprotective benefits for PD in early studies. As such, GlobalData expects that if PRX-002 and Victoza receive approval in PD, they will generate global sales of $2.1 billion and $769 million by 2029, respectively.

“However, high challenges also await these pipeline agents, due to the high failure rate in PD clinical trials, the lack of reliable biomarkers, and the incomplete understanding over the pathophysiology and etiology of the disease. These challenges were confirmed with the recent termination of two PD candidate programs in February 2021, after they failed to achieve their target endpoints in Phase II trials: Biogen’s cinpanemab and Sanofi’s GZ-402671 (venglustat). While the promise of DMTs and neuroprotective therapies has often been met with failure in late-stage trials, a breakthrough therapy in this risky area will be rewarded generously. If any pipeline agent proved to offer even the slightest disease-modifying properties, it would be a treatment game changer within this stagnant area of development,” says Elsayed.