NiaMIT Continuation With Early-stage Mitochondrial Myopathy Patients
NiaMIT Continuation With Early-stage Mitochondrial Myopathy Patients
NCT ID: NCT04538521 Phase: NA Status: COMPLETED Enrollment: 3 Completion: 2020-09-18
Conditions
Mitochondrial Myopathies
Interventions
Niacin
Summary
The most frequent form of adult-onset mitochondrial disorders is mitochondrial myopathy, often manifesting with progressive external ophthalmoplegia (PEO), progressive muscle weakness and exercise intolerance. Mitochondrial myopathy is often caused by single heteroplasmic mitochondrial DNA (mtDNA) deletions or multiple mtDNA deletions, the former being sporadic and latter caused by mutations in nuclear-encoded proteins of mtDNA maintenance. Currently, no curative treatment exists for this disease. However, an NAD+ precursor vitamin B3 has been demonstrated to give power to diseased mitochondria in animal studies by increasing intracellular levels of NAD+, the important cofactor required for the cellular energy metabolism. Vitamin B3 exists in several forms: nicotinic acid (niacin), nicotinamide, and nicotinamide riboside. Nicotinamide riboside has been shown to prevent and improve disease symptoms in several mouse models of mitochondrial myopathy. In addition, the investigators have previously observed that treatment with another form of vitamin B3, niacin, improved NAD+ deficiency and muscle performance in mitochondrial myopathy patients.
In this study, the form of vitamin B3, niacin, is used to activate dysfunctional mitochondria and to rescue signs of mitochondrial myopathy in early-stage patients. Of the vitamin B3 forms, niacin, is employed, because it has been used in large doses to treat hypercholesterolemia patients, and has a proven safety record in humans. Phenotypically similar mitochondrial myopathy patients are studied, as the investigator's previous expertise indicates that similar presenting phenotypes predict uniform physiological and clinical responses to interventions, despite varying genetic backgrounds. Patients with mitochondrial myopathy, typically harboring a sporadic single mtDNA deletion or a mutation in nuclear mtDNA maintenance gene causing multiple mtDNA deletions, are recruited. In addition, data from healthy controls from the primary N
Primary Outcome
NAD+ and related metabolite levels in blood and muscle