Open Label Sumanirole Study of Safety, Tolerability, and Therapeutic Response In Patients With Parkinson's Disease

Inclusion Criteria: * Idiopathic Parkinson's disease * Modified Hoehn and Yahr Scale Stages 1-4 * Age over 30 years * Previous participation in prior sumanirole studies Exclusion Criteria: * Use of dopamine agonist medications and other medications in defined timeframe * Unstable dose of CNS active therapies (eg, hypnotics, antidepressants, anxiolytics) within the last 30 days * Atypical Parkinson's syndromes due to drugs, metabolic disorders, encephalitis, or degenerative diseases * Dementia * History of active epilepsy within the past year * Significant liver disease with defined laboratory criteria * Significant renal disease with defined laboratory criteria * Certain cardiac conditions * Electroconvulsive therapy in the previous 90 days * Subjects participating in other drug studies or receiving other investigational drugs within previous 30 days * Positive pregnancy test at Screen * Unwillingness to use adequate contraceptive methods * Lactating women * History of stereotaxic brain surgery * Malignant melanoma or history of treated melanoma