Pramipexole Extended Release Versus Pramipexole Immediate Release for 18 Weeks in Chinese Parkinson's Disease (PD) Patients

Inclusion criteria

• Male or female Chinese patient with idiopathic Parkinson's disease (PD) confirmed by at least two of the following signs: resting tremor, bradykinesia, rigidity.
• Parkinson's disease diagnosed for at least 2 years.
• Patients 30 years of age or older at the time of diagnosis.
• Modified Hoehn and Yahr stage of 2 to 4 at on-time.
• If a patient is treated with standard or controlled release Levodopa combined with a Dopa-Decarboxylase-inhibitor or with Levodopa combined with a Dopa-Decarboxylase-inhibitor/entacapone, the dosage should be optimised according to investigator's judgement, and stable for at least 4 weeks prior to baseline visit.
• If a patient treated with Levodopa combined with a Dopa-Decarboxylase-inhibitor has motor fluctuations, he should not have more than 6 hours of off-time every day during waking hours (documented on a patient diary completed for 2 consecutive days before baseline visit).
• Patient willing and able to comply with scheduled visits, treatment plan, laboratory tests and other study procedures (in particular, after training, the patient should be able to recognise the off-time and on-time periods during waking hours and to record them accurately in the patient diary).
• Signed informed consent obtained before any study procedures are carried out (in accordance with International Conference on Harmonisation-Good Clinical Practice guidelines and local legislation).

Exclusion criteria

Medical exclusions:

• Atypical parkinsonian syndromes due to drugs (e.g., metoclopramide, flunarizine), metabolic disorders (e.g., Wilson's disease), encephalitis or degenerative diseases (e.g., progressive supranuclear palsy).
• Dementia, as defined by a Mini-Mental State Exam score =20 mmHg in systolic blood pressure and a decline >= 10 mmHg in diastolic blood pressure, at one minute after standing compared with the previous supine systolic and diastolic blood pressure obtained after 5 minutes of quiet rest) at screening or baseline visit.
• Malignant melanoma or history of previously treated malignant melanoma.
• Any other clinically significant disease, whether treated or not, that could put the patient at risk or could prevent compliance or completion of the study.
• Pregnancy (to be excluded by urine pregnancy test at screening visit) or breast-feeding.
• Sexually active female of childbearing potential (less than 6 months post-menopausal and not surgically sterilised) not using a medically approved method of birth control (i.e. oral contraceptives, intrauterine device, or double-barrier) for at least one month prior to the screening visit and throughout the study period (up to the follow-up visit).
• Serum levels of Aspartate Aminotransferase, Alanine Aminotransferase , alkaline phosphatases or total bilirubin > 2 Upper Limit of Normal (on screening lab test).
• Patients with a creatinine clearance < 50 mL/min/1.73m2 (estimated by the local lab / the investigator using the Modification of Diet in Renal Disease (MDRD), and calculated on screening lab test)