Parkinson’s Disease is characterized by a loss of brain cells that produce dopamine. Dopamine is a chemical messenger. Its job is to send information to the parts of the brain that control movement and coordination. Lower than normal brain production of dopamine causes the symptoms of Parkinson's Disease. Some of these symptoms include muscle stiffness, resting tremors and slowing of movements.
Levodopa is a widely used treatment for Parkinson's Disease. It works by increasing the brain's dopamine levels. After some time, treatment with Levodopa becomes less effective. When this happens people with Parkinson's Disease experience "ON and OFF" time.
During “ON” time medication keeps Parkinson's Disease symptoms controlled. During "OFF" time the symptoms of Parkinson's Disease may return.
This clinical study is evaluating the experimental medication tozadenant. Tozadenant will be an added to treatment to Levodopa the medication you are currently on. The goal of this study is to see if this combination of medications can reduce "OFF time" in Parkinson's Disease.
This study requires
-You will visit the study doctor about 14 times -Routine electrocardiogram (heart rhythm evaluation) -Take medication twice daily -Complete home diary
Who can participate?
To be eligible to participate in this study you are on a stable dose of anti Parkinsons medication for at least four weeks prior to entering this study.
The stable anti Parkinson's Disease medication must include at least four doses of a levodopa-containing medication per day and at least one other anti Parkinson's Disease medication.
Benefits and risks of participating
The most common side effect of tozadenant is dyskinesia (unwanted, involuntary twisting movements or jerky motions), which is also a symptom of Parkinson's Disease. Possible benefits and risks will be discussed with you during the consent process.