A Placebo Controlled Double Blind Randomised Controlled Proof of Concept Study of Zolpidem for the Treatment of Motor and Cognitive Deficits in Late-stage Parkinson's

Zolpidem is a hypnotic drug which at sub-sedative doses has been shown to improve both motor and cognitive deficits in stroke, dementia and Parkinson's. This has led to the hypothesis that low-dose zolpidem will be effective in early-stage Parkinson's, delaying the need for dopamine-replacement interventions, as an adjunct therapy, and in late-stage Parkinson's where current interventions are ineffective for motor and cognitive decline. At present, the symptoms of late-stage Parkinson's are the most debilitating and the least well-controlled. Here, the investigators propose a placebo controlled double-blinded proof-of-concept study in order to determine the benefits of taking low-dose zolpidem in late-stage Parkinson's. The study will take place over 12 months. 28 participants, diagnosed with Parkinson's for at least 5 years will be recruited; 14 participants will take zolpidem (5 mg) and 14 placebo, each morning for 4 days. In the clinic (day 1) clinical assessments will include the motor III of the Unified Parkinson's Disease Rating Scale (UPDRS) and cognitive verbal fluency tasks which will be conducted at baseline and 1 hour following drug administration. Each participant will then be issued with a smartphone with application to objectively test their motor performance 4 times a day, over the next six days (3 days on drug, 3 days off drug). This study will provide the necessary data on drug efficacy in order to design a phase II clinical trial for the use of low-dose zolpidem in late-stage Parkinson's.