The purpose of a randomized, double-blind, placebo-controlled, 2-way crossover study is to evaluate the efficacy, safety/tolerability and pharmacokinetics of JM-010 for the treatment of subjects with Parkinson's Disease (PD) with levodopa-induced dyskinesia (LID).

Inclusion Criteria:

• Written informed consent.
• Subject with a diagnosis of moderate to severe idiopathic PD with showing responsiveness to levodopa.
• All anti-Parkinsonian medications and levodopa must be stable for at least 1 week prior to the start of the run-in period.
• Subject with stable predictable peak-effect LID of at least 2 hours of the awake day and with at least moderately disabling.
• Amantadine and/or monoamine oxidase (MAO) inhibitor must be stopped at least 2 weeks prior to the start of Treatment Period 1(TP 1).

Exclusion Criteria:

• Diagnosis is unclear or a suspicion of other Parkinsonian syndromes exists, such as secondary Parkinsonism, Parkinson-plus syndromes or other neurological degenerative diseases.
• History of any other brain surgery or surgery for the treatment of PD.
• Current primary psychiatric diagnosis of acute psychotic disorder or other primary psychiatric diagnoses.
• A history of psychosis and/or treatment with antipsychotics within 3 months prior to the start of Treatment Period 1(TP1).
• A history of, or current, seizure disorders and subjects requiring treatment with anti-convulsants.
• Clinically significant abnormal laboratory data at screening.
• Clinically relevant ischemic heart symptoms or history of myocardial infarction, coronary artery bypass surgery or percutaneous transluminal coronary angioplasty, within the previous 12 months prior to the start of TP1.
• History of cerebrovascular accident or transient ischemic attack, coronary vasospasm/Prinzmetal's angina.
• History of serotonin syndrome.
• Breast feeding or pregnant women.