The NADPARK study: A randomized phase I trial of nicotinamide riboside supplementation in Parkinson's disease
Brakedal B, Dölle C, Riemer F, et al.
Key finding
Oral NR at 1 g/day for 30 days raises cerebral NAD+ in newly diagnosed Parkinson's patients, with transcriptomic and motor-symptom trends favoring treatment. Source: Brakedal B, Dölle C, Riemer F, et al. Cell Metabolism, 2022.
Summary
Randomized, double-blind, placebo-controlled phase I trial of NR in 30 newly diagnosed, drug-naïve Parkinson's disease patients. Participants received 1 g/day NR or placebo for 30 days. Primary outcome was brain NAD+ measured by 31P-MRS. NR supplementation produced a significant increase in cerebral NAD+ and NAD+-related metabolites, with 10 of 13 NR-treated patients classified as biochemical responders. Responders showed upregulation of mitochondrial and metabolic gene programs in peripheral blood mononuclear cells and skeletal muscle, as well as a trend toward clinical symptom improvement on the MDS-UPDRS motor scale. The trial provided the first human evidence that an oral NAD+ precursor can raise NAD+ in the living human brain, directly addressing skepticism about whether NR crosses the blood-brain barrier or its metabolites reach central tissue. Safety was excellent. NADPARK motivated larger follow-up trials (NR-SAFE, NOPARK) and established Parkinson's disease as a leading neurodegeneration indication for NAD+ therapeutics.
For background on the compound studied here, see our NR precursor reference.
Frequently asked questions
- What did Brakedal et al. (2022) find about NR?
- Oral NR at 1 g/day for 30 days raises cerebral NAD+ in newly diagnosed Parkinson's patients, with transcriptomic and motor-symptom trends favoring treatment. Source: Brakedal B, Dölle C, Riemer F, et al. "The NADPARK study: A randomized phase I trial of nicotinamide riboside supplementation in Parkinson's disease." Cell Metabolism, 2022.
- What kind of study is Brakedal 2022?
- It is a clinical trial on NR published in Cell Metabolism in 2022. Randomized, double-blind, placebo-controlled phase I trial of NR in 30 newly diagnosed, drug-naïve Parkinson's disease patients. Participants received 1 g/day NR or placebo for 30 days. Primary outcome was brain NAD+ measured by 31P-MRS. NR supplementation produced a significant increase in cerebral NAD+ and NAD+-related metabolites, with 10 of 13 NR-treated patients classified as biochemical responders. Responders showed upregulation of mitochondrial and metabolic gene programs in peripheral blood mononuclear cells and skeletal muscle, as well as a trend toward clinical symptom improvement on the MDS-UPDRS motor scale. The trial provided the first human evidence that an oral NAD+ precursor can raise NAD+ in the living human brain, directly addressing skepticism about whether NR crosses the blood-brain barrier or its metabolites reach central tissue. Safety was excellent. NADPARK motivated larger follow-up trials (NR-SAFE, NOPARK) and established Parkinson's disease as a leading neurodegeneration indication for NAD+ therapeutics.
- Where can I read the full Brakedal 2022 paper?
- The primary source is available on PubMed (PMID 35235774) and via DOI 10.1016/j.cmet.2022.02.001.
Access the full paper
Related research
Nature Communications · 2016
Nicotinamide riboside is uniquely and orally bioavailable in mice and humans
NR is orally bioavailable in humans and raises blood NAD+ without flushing.
Cell Reports · 2019
Nicotinamide riboside augments the aged human skeletal muscle NAD+ metabolome
NR raises tissue NAD+ in aged muscle and shifts mitochondrial transcription.
Scientific Reports · 2019
Safety and metabolism of long-term administration of NIAGEN (Nicotinamide Riboside Chloride) in healthy middle-aged and older adults
NR is well tolerated at doses up to 1 g/day over 8 weeks in healthy adults.