ME2125 Phase II/III (ME2125-3)

INTERVENTION: Intervention name : ME2125 INN of the intervention : safinamide Dosage And administration of the intervention : Orally administer a dose of 2 tablets once a daily in morning. Control intervention name : Placebo Dosage And administration of the control intervention : Orally administer a dose of 2 tablets once a daily in morning. CONDITION: Parkinson's disease PRIMARY OUTCOME: "on" time SECONDARY OUTCOME: "on" time, "off" time, Unified Parkinson's Disease Rating Scale (UPDRS), 39‐item Parkinson's Disease Questionnaire (PDQ‐39), responder rate, adverse event, adverse drug reaction, laboratory tests INCLUSION CRITERIA: Major INCLUSION CRITERIA: ‐ Patients must be able to understand and willing to sign an informed consent form (If the patient has difficulty in writing, his/her caregiver must sign an informed consent form). ‐ Patients must have a diagnosis of Parkinson's disease meeting UK Parkinson's Disease Society Brain Bank diagnostic criteria. ‐ Patients must have a modified Hoehn and Yahr stage of II‐IV during an "off" phase at screening. ‐ Patients must have been receiving treatment with any levodopa combination drug for more than 24 weeks at screening and have a wearing‐off phenomenon with expected "off" time.