Prostate cancer drug could slow down Parkinson's disease

The findings, published in the Journal of Clinical Investigation, stemmed from previous research by one of the co-authors, Lei Liu at Capital Medical University in Beijing, which found that the prostate drug, terazosin, could block cell death.

This protective property of the drug was found to be due to terazosin's ability to activate an enzyme which is critical for cellular energy production. As reduced cellular energy production is a key feature of Parkinson's disease (PD), the team made the link between the drug and the potential to slow down the progression of Parkinson's.

Using experimental models of Parkinson's in animals, the researchers found that terazosin could prevent, slow or stop neurodegeneration if the drug was given before cells could die, even if treatment was delayed until after neurodegeneration had started.

"When we tested the drug in various different animal models of PD, they all got better. Both the molecular changes in the brain associated with cell death and the motor coordination in the animals improved," said Liu.

Based on these results, the researchers looked into existing data on older men who had Parkinson's and were also taking terazosin for an enlarged prostate or drugs which also activated the cellular energy enzyme.

Looking at data from 2,880 men taking the drugs compared to a control group, the results showed that terazosin and related drugs reduce the symptoms and complications of PD.

"Current medicines can partially alleviate some of the symptoms of Parkinson's disease. But today we have zero treatments that change the progressive course of this neurodegenerative disease," said senior author Michael Welsh of the University of Iowa. "I'm really excited about this finding because I think it has the opportunity to change the lives of people with Parkinson's disease (and possibly other types of neurodegenerative disease)."

"What is particularly exciting is that terazosin is a 'repurposed drug'. So, we have a lot of safety data already from its clinical use to treat an enlarged prostate," said Nandakimar Narayanan, a neurologist who cares for patients and studies PD. "We are currently engaged in planning phase 1 studies that are funded and we are recruiting patients in Iowa. This is the beginning of what we hope is a sustained and rigorous effort to test this molecule prospectively in order to really determine whether this works."

This study was published in the Journal of Clinical Investigation.