Inclusion Criteria:

• Patients aged 30-80 years
• Patients with idiopathic Parkinson's disease corresponding to stages II-IV according to the classification of Hoehn and Yahr during an "on" period, and/or patients in whom the individual optimized dosage of levodopa (and decarboxylase inhibitor) causes motor fluctuations characterized as end-of-dose phenomena or "wearing-off" effects for at least 30 days prior to initial administration of study medication and whose daily total "off" time is at least 2 hours and no more than 6 hours during waking time.
• Patients able to keep an accurate patient diary of the times of "on"- and "off"-periods during waking hours. Family members, guardians or nursing personnel may assist the patient.
• Informed Consent (consent in writing)

Exclusion Criteria:

• Patients with atypical parkinsonian syndromes due to drugs, metabolic disorders , encephalitis, or degenerative disease.
• Dementia that could impair compliance with medication, impair maintenance of accurate patient diaries, and/or preclude the signing of informed consent.
• History of psychosis except that which was elicited by treatment with levodopa or dopamine agonists unless the patient remains psychotic and in the opinion of the investigator would be unable to participate in the study.
• History of active epilepsy within the last two years prior to Visit 2.
• Patients with second or third degree AV block or sick sinus syndrome.
• Patients with resting heart rate below 50 beats per minute.
• Patients with congestive heart failure classified as functional Class III or IV by the New York Heart Association.
• Patients with myocardial infarction within six months of randomization.
• Patients with other clinical significant heart conditions which would negatively impact on the patient completing the study.
• Clinically significant kidney disease which may prevent the patient from completing the study and/or an elevation in either blood creatinine or urea nitrogen >1.5 times the laboratory normal.
• Clinically significant liver disease which may prevent the patient from completing the study and/or an elevation in either total bilirubin, SGPT, or SGOT of >1.5 times the laboratory normal.
• Retinopathia pigmentosa
• Presence of active neoplastic disease
• Patients with surgery within 180 days of Visit 2 which in the opinion of the investigator would negatively impact on the patient's participation in the clinical study or a history of stereotaxic brain surgery.
• At screening supine systolic blood pressure less than 100mmHg or evidence of a 20 mmHg decline in systolic blood pressure at one minute after standing compared with the previous supine systolic blood pressure obtained after 5 minutes of quiet rest in the supine position if the decline in blood pressure upon standing is associated with symptoms. Blood pressure at study entry (supine and standing) is expressed as the average of the second and third measured values.
• Patients who have received any of the following drugs during the 30 days prior to administered of study medication unless a longer period of time is specifically noted: neuroleptics (60 days), a-methyl-dopa, metoclopramide (60 days), flunarizine, cinnarizine, parenteral ergot preparation, bromocriptine, pergolide, A monoamine oxidase (MAO) inhibitors excluding l-deprenyl, methylphenidate hydrochloride, amphetamine derivatives, beta blockers (e.g. propranolol) only if used as an adjunctive treatment for PD, or reserpine.
• Females of childbearing potential not using oral contraceptives or a medically recognized mechanical means of contraception.
• Electroconvulsive therapy within 90 days of Visit 2.
• Patients who are participating in other drug studies or who receive other investigational drugs within 30 days prior to Visit 2, nor the patients previously randomized into this study.