Inclusion Criteria:
Diagnosis and main criteria for inclusion. Patients must meet all of the following inclusion criteria to be eligible for enrollment into the study:
- Patients with idiopathic Parkinson's disease of less than 7 years characterized as Stage I-III by the Modified Hoehn and Yahr Scale and with a maximum of 6 months cumulative lifetime exposure to levodopa and/or dopamine agonist. Patients on current dopamine agonist therapy would require 14-day washout.
- Age at least 30 years.
- Women of childbearing potential must have a negative serum beta-HCG pregnancy test at the Screen (Baseline) visit and the patient must use adequate contraceptive methods.
- Evidence of a personally signed and dated informed consent document indicating that the patient (or a legally acceptable representative) has been informed of all pertinent aspects of the study.
- Patients who are willing and able to comply with scheduled visits, treatment plan, and other study procedures.
Exclusion Criteria:
Main criteria for exclusion. The presence of any of the following would make a patient ineligible for enrollment into the study:
- Previous history of allergic response or complications with any dopaminergic agonist drug
- Atypical PD syndromes
- History of stereotactic brain surgery
- Positive hepatitis B (surface antigen) or hepatitis C (antibody)
- Surgery within 180 days of randomization which would negatively impact participation
- Folstein's Mini Mental State Examination (MMSE) score of 24 or less
- History of active epilepsy (seizure) in the past 1 year
- Third degree AV block or sick sinus syndrome
- Congestive heart failure, Class III or IV
- Unstable heart disease such as unstable angina, dysrhythmia, or myocardial infarction in prior 6 months
- Symptomatic orthostatic hypotension
- Clinically significant liver disease or renal disease
- Malignant melanoma or history of previously treated malignant melanoma.
- Prohibited medications taken (including any drug known to have potential retino-toxic effects taken in the prior 12 months; neuroleptics taken within prior 6 months, MAO inhibitors except rasagiline or selegiline taken within prior 3 months, beta-blockers taken to treat Parkinson's disease in the prior 30 days, and Coenzyme Q10 taken within 14 days)
- Albinism/Albinoidism of any degree, type or syndrome
- History of glaucoma with or without treatment
- Inherited or acquired retinopathy such as age-related macular degeneration with visual loss
- Sarcoidosis
- Diabetes mellitus of any degree even if diet or insulin controlled
- Best corrected visual acuity (BCVA) of less than 20/40 by ETDRS
- Refractive error of greater than minus-6 diopters
- Abnormal electroretinogram (ERG)
- Unable to dilate pupils
23. History of severe eye trauma that might affect the outcome of the study 24. History of psychosis 25. Participation in other investigational drug studies or use of investigational drugs within prior 30 days