I think the main problem for a PD treatment is the poor knowledge of brain chemistry, the interactions among its different parts and the whole brain-body interaction.

My understanding is that current treatments are mostly focused on the lack of dopamine, and there's a need to target the other uncontrolled chemicals in our brains: glutamate, GABA, Fe, Ca, alpha-synuclein.

But my hope is that scientists will indeed find a way to stop PD. They have now much more powerful tools to research and, though it might seem a little rude, there's big business for those who find the cure (and that is a powerful incentive in today's business world).