A Phase 1 interventional study of N-Acetylcysteine in Mitochondrial Disease, sponsored by Michio Hirano, MD. Recruiting at 1 site in United States. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-01-23.
Sponsored by Michio Hirano, MD · Phase 1, Interventional, and Treatment
N-Acetylcysteine (NAC), an anti-oxidant, will be studied to investigate the effects on brain glutathione levels, cognitive skills, motor skills, and quality of life.
A group of 18 participants will take either 1800, 3600 or 5400 mg per day of N-acetylcysteine (NAC) for 3 months in this dose escalation study. The investigators want to determine first if the 3600 mg dose per day is safe and might provide some efficacy. If the 3600 mg dose is safe, then additional participants will be treated with 5400 mg per day of NAC, for up to a total of 18 participants. If the 3600 mg per day dose is unsafe, then participants will be treated with the 1800 mg per day dose. Data from this pilot study will be used to determine the most safe and effective dose of NAC for a future clinical trial.
Patients with the m.3243A>G mitochondrial mutation often have low brain glutathione levels. These low levels can reduce the repair processes in the brain to fix toxic chemicals that result from a mitochondrial disorder. The investigators are aware of a potent anti-oxidant, called N-Acetylcysteine (NAC), that may improve the brain glutathione level when taken in sufficient quantity. In turn, cognitive and motor skill impairment may improve as these toxic levels are reduced. will be studied to investigate the effects on brain glutathione levels, cognitive skills, motor skills, and quality of life.
189 studies on the registry are indexed under Mitochondrial Diseases; 60 are open to participants now.
This study's planned enrollment of 18 is below the median of 35 across 114 interventional studies indexed under Mitochondrial Diseases.
Browse Mitochondrial Diseases studies →Michio Hirano, MD is the lead sponsor of 2 studies on the registry; 1 is open to participants now.
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Exclusion Criteria:
Participants will receive NAC for 3 months.
Drug: N-Acetylcysteine
1800, 3600 or 5400 mg NAC per day (divided into 3 daily doses) depending on dose toxicity plan
Also known as: NAC
Maximum tolerated dose (MTD) of NAC
Establish maximum tolerated dose of NAC by initiating dosing at one level, then increasing or decreasing dose based on toxicity. The MTD is defined as the dose associated with a target probability of dose limiting toxicity (DLT) of 0.10.
Time frame: 4 months
Columbia Neurological Score
The Columbia Neurological Score evaluates patients with cerebral energy failure syndromes and quantifies key neurological examination domains. The Columbia Neurological Score ranges from 0 to 76 with higher scores indicating less clinical severity.
Time frame: 4 months
Change in Global Neuropsychological Score
A composite global neuropsychological score is used to assess loss of cognitive function. The global neurological score is derived from measures across a standard neuropsychological battery. Test domains include: Memory, Orientation, Abstract reasoning, Dementia,Language,Word Association, and Naming. The scores range from 0 to 2 with higher scores indicating worsening cognitive function.
Time frame: 4 months
Change in Functional Exercise Capacity (6 minute walk test (6MWT))
The 6MWT is an objective evaluation of functional exercise capacity assessing the distance a person can walk in six minutes.
Time frame: 4 months
Change in Karnofsky Performance Scale (KPS) Score
KPS assesses functional activities of daily living (ADL). Scores range from 0 to 100 with a score of 0 defined as death and 100 defined as normal; no complaint; no evidence of disease (better outcome).
Time frame: 4 months
Change in Brain glutathione (GSH) level
As measured by brain Magnetic resonance Imaging and Magnetic resonance spectroscopy.
Time frame: 4 months
Plan to share: No
No publications or documents are linked to this record.
Started Jul 2023 (actual). Primary completion is estimated for Mar 2026, 32 months after the start.
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Studies of the drug tested here: Acetylcysteine
Michio Hirano, MD