Marios Politis: Roche Announces Prasinezumab Study

Professor Marios Politis is a Consultant Neurologist and a Professor of Neurology. He is also the Director of Neurodegeneration Imaging Group, as well as serving as the Director of Mireille Gillings Neuroimaging Centre at the University of Exeter. Professor Politis has conducted considerable, high-quality research investigating the pathophysiology of neurological disorders like Huntington’s and Parkinson’s disease. He also writes for high impact scientific journals such as the Lancet, Nature and Science journals. This article will explore the potential of Prasinezumab by Roche as an effective treatment for neurodegenerative disorders.

Roche is currently running clinical trials across five countries to evaluate the efficacy of Prasinezumab in slowing or halting disease progression in participants with early Parkinson’s disease. This multicentre, double-blind, randomised, placebo-controlled Phase II study has been designed to evaluate the effectiveness of intravenous Prasinezumab versus a placebo over a 52-week period, treating individuals with early Parkinson’s disease who are either untreated or treated with monoamine oxidase B inhibitors since baseline.

The study will consist of three parts: first, a 52-week, placebo-controlled, double-blind treatment period (Part 1). Eligible participants will then be invited to continue in an all-participants-on-treatment blinded dose extension over a further 52-week period. Participants who complete Part 2 will then be invited to take part in Part 3, an open label, all-participants-on extension for a further 260 weeks.

Roche’s Prasinezumab clinical trial is designed to test whether the drug can halt or slow disease progression in individuals who have received a diagnosis of Parkinson’s disease in the past two years. Participants must be in the early stages of the disease, without having started symptomatic treatment with dopamine agnostics or Levodopa. In Part 1 of the trials, Parkinson’s disease patients will receive monthly injections of Prasinezumab, or a placebo, for 52 weeks. Part 1 participants will be divided into three groups: one group receiving a high-dose intravenous infusion; one group receiving a lower dose intravenous infusion, and one group receiving a non-active medicine, or placebo, administered as an intravenous infusion. All participants have a one in three chance of being placed in any of the three groups.

In Part 2, all patients will who successfully completed Part 1 will be offered Prasinezumab. Participants who received low or high-dose Prasinezumab in Part 1 will continue to receive the same dose for a further 52 weeks. Participants placed in the placebo group in Part 1 will be split at random into two groups, with one group given high-dose Prasinezumab for 52 weeks, and the other receiving low-dose Prasinezumab for 52 weeks.

Neither patients nor their clinical trial doctors have the option of choosing which group they are in. However, clinical trial doctors can find out which group a patient is in if their safety is at risk.

Patients are free to stop treatment at any time. After the treatment has been administered, they will attend regular visits with their clinical doctor, enabling medical professionals to check how they are responding to the treatment and report any side effects they may be having.

In early 2021, hopes were dashed regarding what was considered one of the main assets in the fight against Parkinson’s disease. On the 3rd of February 2021, Biogen announced that it was discontinuing developing the drug Cinpanemab after it failed the Phase II proof-of-concept trial. Similarly, on the 5th of February, Sanofi announced that its asset, Venglustat, had failed in Phase II clinical trials. Roche’s Prasinezumab is widely touted as the main player in tackling Parkinson’s disease currently, preventing aggregation of the α-synuclein protein and potentially halting progression of the disease.