Overview Study of KW-6002 (Istradefylline) in Parkinson's Disease in Patients With Motor Response Complications on Levodopa Status: Completed Trial end date: 2007-02-01 Target enrollment: Participant gender: Summary The purpose of this study is to confirm the long term tolerability and safety of oral 20 or 40 mg/d doses of Istradefylline. Phase: Phase 3 Details Lead Sponsor: University of ChicagoTreatments: IstradefyllineLevodopa