On a lark I Googled "Hydroxychloroquine Parkinson's" and actually found some stuff (leave no stone):
Scientists have found that existing anti-malaria drugs could be a potential treatment for Parkinson's disease 2015 sciencedaily.com/releases/2...
Chloroquine, the Coronavirus Crisis, and Neurodegeneration: A Perspective frontiersin.org/articles/10...
Here we provide a perspective on the potential interaction of CQ and the neuronal dyshomeostasis observed in common degenerative disorders such as Alzheimer's or Parkinson's disease. We consider the pharmacodynamics and pharmacokinetic attributes of CQ, and its potential effects on the nervous and immune systems.