Auckland City Hospital neurologist Dr Barry Snow, who led the research, yesterday presented the results to a conference in San Diego.
He said the team were encouraged by the positive results and would work on carrying out a larger study.
"Currently, clinicians are able to manage only symptoms in patients with Parkinson's disease as there are no disease-modifying treatments available that can reverse the underlying progressive degeneration of neurons in the brain."
In New Zealand, one in every 500 people have the disease.
Most people with Parkinson's are aged 65 or older, but the average age of diagnosis is 59 years old.
One of the patients in the trial, Aucklander Carol - who did not want her surname published - said she had noticed a marked difference in her speech and control of her body.
"The most important [change] is that I've regained my joie de vivre.
"I've got better control of my little fingers of my left hand and that's great. It's very encouraging. I am getting my speaking voice again ... I can actually converse with people."
Parkinson's NZ acting head Stephanie Clare said the organisation was excited for the hope it would bring to thousands of Kiwis.