Abstract
Background Prior research identified profound sleep disruption in PSP. The hypothalamic and brainstem, areas that help regulate the sleep/wake patterns, are among regions earliest effected. Comparing polysomnography and quantitative-neuropathology metrics, we identified relative sparing of wake promoting nuclei in PSP compared to Alzheimer’s disease, though PSP had more disrupted sleep. It led to the hypothesis that PSP patients have hyperinsomina due to degeneration of sleep nuclei with a preservation of sleep neurons, causing a system unbalance. Higher neuronal count of wake-promoting nuclei was associated with greater nocturnal wake, regardless of disease. Specifically, orexinergic wake-promoting neurons in the lateral hypothalamus, previously described as the sleep-on/off switch, are relatively spared in PSP. Thus, we hypothesized that an orexinergic antagonist may be more effective in treating sleep/wake issues in PSP than other hypnotic medications. This study tests the safety and efficacy of an orexinergic antagonist (suvorexant) targeting the wake-promoting system and contrasts it to a GABAergic receptor agonist (zolpidem) targeting sleep-promoting systems.Methods This is a remote clinical trial, designed as a double-blind, cross-over, within-subject 6-week trial, with 3 one-week long conditions, separated by 1 week washout periods. The order of the 3 regiments is randomized and counterbalanced: placebo (microcrystalline cellulose), 15mg suvorexant, 5mg zolpidem. Participants are recruited from doctor and study referrals, registries, and support groups. Once onboarded, the trial-coordinator maintains communication with the participant/caregiver throughout the 6 weeks. Assessments include neurological interviews, cognitive testing, and subjective questionnaire packets. Sleep and circadian rhythm are assessed through ambulatory EEG and actigraphy monitoring devices worn by the participant throughout the trial.Discussion The study design aims to reduce burden and improve accessibility. Administering a remote clinical trial for a rare disease, however, creates unique issues that would otherwise be absent from in-person studies. Particularly, a symptom rather than disease-modifying trial is challenging to recruit for when potential disease-modifying therapeutics are available. Needing to coordinate with non-associated medical offices to attain medical records or prescriptions can cause frustrations for the potential participant, medical office, and study team. In recruitment, onboarding, and trial maintenance, this study design relies on consistent communication to support participant enrollment and satisfaction.Trial Registration “Treatment of Disturbed Sleep in Progressive Supranuclear Palsy (PSP)”; NCT04014389