A Study of Istradefylline (KW-6002) in Treating Patients With Parkinson's Disease on Levodopa
A Study of Istradefylline (KW-6002) in Treating Patients With Parkinson's Disease on Levodopa
To establish the efficacy of 10, 20 and 40 mg/d dose of istradefylline for reducing the
 percentage of OFF time in patients with advanced Parkinson's disease (PD) treated with
 levodopa.
To establish the efficacy of 10, 20 and 40 mg/d dose of istradefylline for reducing the
 percentage of OFF time in patients with advanced Parkinson's disease (PD) treated with
 levodopa. Patients who meet entry criteria will be randomized in a 1 to 1 ratio to either
 istradefylline 10, 20 or 40 mg or matching placebo. Patients will be treated for 12 weeks and
 will have interim visits and end of treatment visit to assess efficacy and safety.
Inclusion Criteria:

 1. UK Parkinson's Disease Society (UKPDS) brain bank criteria (Step 1 and 2) for PD.

 2. PD stages 2-4 in the OFF state for Modified Hoehn and Yahr Scale.

 3. On levodopa/carbidopa for at least one year, stable dose in past 4 weeks.

 4. Currently take at least three doses of levodopa/carbidopa per day.

 5. Predictable end of dose wearing off.

 6. Able to satisfactorily complete Hauser version of a Parkinson's diary.

 7. Have an average of 180 minutes of OFF time on two 24 hour diaries.

 8. Be at least 30 years of age.

 Exclusion Criteria:

 1. Neurosurgical treatment for PD.

 2. History of psychosis.

 3. Diagnosis of atypical parkinsonism, secondary parkinsonism variant or Parkinson's plus
 syndromes.

 4. Diagnosis of cancer within 5 years.

 5. Mini-mental status examination score of 25 or less.

 6. History of seizures or neurologic malignant_syndrome.