NORTHERA (DROXIDOPA) for Dysautonomia in Pediatric Survivors of Menkes Disease

This clinical trial will evaluate the safety, tolerability, dosing, and efficacy of Northera (Droxidopa) in children with Menkes disease aged 7 to 17 years who survived the major neurodegenerative and neurocognitive effects of Menkes disease through early Copper Histidinate treatment. The investigator hypothesizes that Northera (Droxidopa) treatment in pediatric Menkes disease survivors with symptoms of dysautonomia (e.g., syncope, dizziness, orthostatic hypotension, abnormal sinoatrial conduction, and bowel or bladder dysfunction) from deficiency of the cuproenzyme, dopamine-beta-hydroxylase, will be safe and will correct or improve blood neurochemical levels, raise systolic blood pressure, and produce symptomatic improvement and a better quality of life. The investigator will test this hypothesis, in six to ten child or adolescent Menkes disease survivors through a placebo-controlled trial to evaluate adverse event rates and whether oral administration of Northera (Droxidopa) at doses established for individual subjects by careful dose titration improves plasma norepinephrine and dihydroxyphenylglycol (DHPG) levels, raises systolic blood pressure, and improves performance on tests of physical exertion. As an exploratory outcome measure, the study will validate the Orthostatic Hypotension Symptom Assessment (OHSA) questionnaire for this population for two four-week periods of either active or placebo treatment. Aim 1. Determine the safety of Droxidopa in Menkes disease pediatric survivors. Aim 2. Determine the efficacy of Droxidopa in Menkes disease survivors. The investigator hypothesizes that low-dose Droxidopa treatment in classic Menkes disease survivors aged 7 to 17 will improve orthostatic hypotension and ameliorate other signs and symptoms of dysautonomia. This pilot study will employ an ascending dose paradigm in a double-blind placebo-controlled randomized crossover design to optimize statistical power and rigorously discern treatment effects on 1) tilt table tests of orthostatic hypotension, 2) systolic and diastolic blood pressure, 3) plasma neurochemical levels and 4) tests of physical exertion. The trial will also validate the Orthostatic Hypotension Symptom Assessment (OHSA) questionnaire for this population of children and adolescents. This study addresses an important unmet clinical need for subjects with a rare disease, Menkes disease.