Dipraglurant (ADX48621) for the Treatment of Patients With Parkinson's Disease Receiving Levodopa-based Therapy

Inclusion Criteria:

• Patients with Parkinson's Disease on a stable regimen of antiparkinson's medications,including a levodopa preparation administered not less than 3 times daily.
• Meet protocol-specified criteria for moderate to severe dyskinesia symptoms based onUDysRS and Movement Disorder Society - Unified Parkinson's Disease Rating Scale (MDS-UPDRS) assessments.
• Meet protocol specified criteria for ON time with troublesome dyskinesia based on astandard PD home diary.

Exclusion Criteria:

• Prior surgical treatment for Parkinson's Disease (e.g., deep brain stimulation).
• Other neurological disease (including psychiatric disease and/or cognitive impairment)that, in the opinion of the investigator, would affect the patient's ability tocomplete study assessments.
• Other significant medical condition that may affect the safety of the patient orpreclude adequate participation in the study.
• Pregnant or breast-feeding. Female patients who are of child-bearing potential must beusing adequate contraceptive methods (e.g. oral contraceptive, double-barrier method,intra-uterine device, intra-muscular hormonal contraceptive), and have a negativepregnancy test at Screening. Other protocol-defined inclusion and exclusion criteria may apply