Parkinson's disease is a progressive neurological disorder characterized by tremor, bradykinesia, rigidity, gait and postural instability and a variety of nonmotor symptoms. While levodopa effectively alleviates all symptoms of Parkinson's disease and restores motor function, within 3 to 5 years the majority of Parkinsonian patients develop levodopa-induced side effects, mainly dyskinesias (involuntary and uncontrolled movements such as twisting of a hand or a limb) and wearing off (progressive shortening of therapeutic response duration). Dyskinesias are the most disabling side effects of long term levodopa therapy in Parkinsonian patients. There is currently no approved drug for levodopa-induced dyskinesia.~The effects of three single ascending doses of orally administered Neu-120 will be evaluated in a double blind placebo controlled crossover proof of concept study. Following a 1-day screening visit, patients will be randomized to receive three single ascending doses of Neu-120 and placebo.~Patients will be admitted to the clinic on the evening prior to each visit on five occasions, each separated by 7 (-3) days. Levodopa challenges will be performed at baseline (visit 1) and at each treatment visit after withdrawal of all antiparkinsonian medications for 12 hours.~Blood samples will be taken for measurement of Neu-120 and levodopa plasma levels.~Primary parameter is improvement in levodopa-induced dyskinesia. Secondary parameters are safety, tolerability, pharmacodynamic assessments of dyskinesias and motor function, Neu-120/levodopa pharmacokinetic profiles and correlation between pharmacodynamic effects and Neu-120/levodopa levels.
The purpose of this study is to determine the safety, tolerability, pharmacokinetic and pharmacodynamic effects of single doses of Neu-120 in Parkinson's disease patients with levodopa-induced dyskinesia.