A developmental drug to treat Parkinson’s disease has shown promise in slowing symptoms of motor deterioration in people with advanced forms of the condition, according to a study published in Nature Medicine.

Prasinezumab is a monoclonal antibody which has been shown to beneficially affect clusters of misfolded alpha-synuclein protein in the brain. Accumulation of this protein has been indicated in debilitated motor coordination in those with Parkinson’s.

Results from an exploratory analysis of phase II study data have shown both high- and low-doses of prasinezumab can significantly reduce the rate at which motor symptoms worsened over the year-long study period, in those with advanced forms of the condition.

In contrast, the drug showed no meaningful impact in those with early-stage Parkinson’s.

This could be because people with more progressed Parkinson’s have larger amounts of misfolded alpha-synuclein in their brains, so would potentially benefit more from a drug that reduces the protein’s accumulation.

“The results imply that in a faster-progressing population, where the degree of worsening over time is greater, there is an increased likelihood of a potential treatment effect,” said study lead Gennaro Pagano from Roche, the company that developed the drug.

The team were unable to confirm that the drug is disease-modifying since, due to the lack of a biomarker in the trial, it is unclear whether the drug actually clears the proteins from the brain.

However, Pagano says the results have highlighted the need for further research into whether prasinezumab is effective in people with milder Parkinson’s disease when taken over a longer period.


Further reading

Nature Medicine: Prasinezumab slows motor progression in rapidly progressing early-stage Parkinson’s disease