New findings published in JAMA Neurology from research into a potentially protective therapy for Parkinson’s disease show that with medical supervision, urate levels may safely be raised while mitigating risk of complications such as gout. Previous research showed that higher levels of the antioxidant urate were associated with lower risk and slower progression of the disease
In the phase II SURE-PD (Safety of urate elevation in Parkinson’s disease) study—led by Parkinson Study Group investigators and funded by The Michael J Fox Foundation for Parkinson’s Research—researchers found that oral ingestion of the urate precursor inosine is safe and tolerable and raises levels of urate in the blood and in the cerebrospinal fluid bathing the brain.
SURE-PD was developed after the results from two previous prospective studies showed higher levels of urate in serum or cerebrospinal fluid at baseline predicted slower rates of Parkinson’s progression, as measured clinically and with imaging technologies. Raising urate levels also was found to be neuroprotective in pre-clinical models of the disease.
Parkinson’s patients should not self medicate with inosine (which is commercially available), researchers warn, as it has not been proven as a therapy for Parkinson’s and high doses can cause side-effects such as gout and kidney stones and possibly high blood pressure. According to a press release, more research into inosine is needed to characterise the effect on Parkinson’s and, if positive, define dosage and treatment regimens.
“We intend to find out whether inosine can be used as a protective therapy to delay Parkinson’s in people at risk and slow disease progression in those already diagnosed,” says lead investigator Michael Schwarzschild, Massachusetts General Hospital, Boston, USA. “Such a disease-modifying therapy is a critical goal of Parkinson’s disease research, and would greatly improve quality of life and prognosis for the millions living with this disease”.
Schwarzschild also cites the potential of urate as a biomarker. Learning more about how urate levels present in different stages of Parkinson’s could help researchers to identify people at higher risk of the disease, who may benefit from earlier intervention and therefore stratify clinical trials toward individuals with higher likelihood to respond to the treatment.
The Michael J Fox Foundation invested more than US$5 million in SURE-PD in 2008.
The SURE-PD investigators call for “the development of a more definitive trial to investigate the ability of inosine treatment to slow clinical progression among persons with early Parkinson’s disease who have lower urate”.