A Long-Term Extension Trial From Phase II/III of SPM 962 in Early Parkinson's Disease Patients

Inclusion Criteria: * Subject completed the preceding trial 243-07-001 (NCT00537485) Exclusion Criteria: * Subject discontinued from the preceding trial 243-07-001. * Subject had a serious adverse event which association with the investigational drug was not ruled out during trial 243-07-001. * Subject has a persistent serious adverse event at the baseline, which was observed and association with the investigational drug was ruled out during trial 243-07-001. * Subject had persistent hallucination or delusion during trial 243-07-001. * Subject has psychiatric conditions such as confusion, excitation, delirium, abnormal behaviour at the baseline. * Subject has orthostatic hypotension or a systolic blood pressure (SBP) \<= 100 mmHg and has a decrease of SBP from spine to standing position \>= 30 mmHg at baseline. * Subject has a history of epilepsy, convulsion etc. during trial 243-07-001. * Subject develops serious ECG abnormality at the baseline. * Subject has QTc-interval \>= 500 msec at the baseline or subject has an increase of QTc-interval \>= 60 msec from the baseline in the trial 243-07-001 and has a QTc-interval \> 470 msec in female or \> 450 msec in male at the baseline. * Subject has a serum potassium level \< 3.5 mEq/L at the end of the taper period in trial 243-07-001. * Subject has a total bilirubin \>= 3.0 mg/dL or AST(GOT) or ALT(GPT) greater than 2.5 times of the upper limit of the reference range (or \>= 100 IU/L) at the end of the period in trial 243-07-001. * Subject has BUN \>= 30 mg/dL or serum creatinine \>= 2.0 mg/dl at the end of the taper period in trial 243-07-001. * Subject who plans pregnancy during the trial. * Subject has dementia. * Subject is unable to give consent. * Subject is judged to be inappropriate for this trial by the investigator for the reasons other than above.