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A Phase 2b Study of Istradefylline (KW-6002) for the Treatment of Parkinson's Disease in Patients Taking Levodopa

Placebo-controlled, Double-blind, Parallel Group, Fixed Dose Study of KW-6002 (Istradefylline) in the Treatment of Parkinson's Disease (Phase 2 Study)

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00455507
Enrollment
363
Registered
2007-04-03
Start date
2007-03-31
Completion date
2008-08-31
Last updated
2012-08-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Parkinson's Disease

Keywords

Parkinson's disease, levodopa, end of dose wearing off, OFF time

Brief summary

The purpose of this study is to establish the efficacy of 20 mg/day and 40 mg/day doses of istradefylline for reducing the mean total hours of awake time per day spent in the OFF state in patients with advanced Parkinson's disease (PD) treated with levodopa.

Detailed description

To establish the efficacy of 20 mg/day and 40 mg/day doses of istradefylline for reducing the mean total hours of awake time per day spent in the OFF state in patients with advanced Parkinson's disease (PD) treated with levodopa. Patients who meet entry criteria will be randomized in a 1:1:1 ratio to double blind treatment with oral doses of 20 or 40mg/day istradefylline or matching placebo. Patients will be treated for 12 weeks and will have interim visits and end of treatment visit to assess the efficacy and safety of istradefylline.

Interventions

Two 10 mg KW-6002 tablets orally once daily for 12 weeks

DRUGPlacebo

Two placebo tablets orally once daily for 12 weeks

Sponsors

Kyowa Kirin Co., Ltd.
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
20 Years to No maximum
Healthy volunteers
No

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/dopa-decarboxylase inhibitor for at least one year. 4. Taking at least three doses and \>=300mg of levodopa per day for at least four weeks before randomization. 5. Predictable end of dose wearing off. 6. Able to satisfactorily complete Hauser based 24-hour patient Parkinson's diary. 7. Have an average of two hours of OFF time on 24-hour diaries. 8. On a stable regimen of any other anti-Parkinson's drugs for at least four weeks before randomization. 9. Be at least 20 years of age. 10. Be willing and able to give written informed consent.

Exclusion criteria

1. Taking any excluded medications. 2. Neurosurgical treatment or Transcranial Magnetic Stimulation for PD. 3. Diagnosis of cancer within 5 years. 4. Diagnosis of clinically significant illness of any organ system. 5. Diagnosis of dementia or mini-mental status examination score of 25 or less. 6. History of drug or alcohol abuse or dependence within the past two years. 7. History of psychosis. 8. Significant drug allergies. 9. Taking anticonvulsants for seizures. 10. History of neurological malignant syndrome. 11. Pregnant or lactating females.

Design outcomes

Primary

MeasureTime frame
To establish the efficacy of 20 mg/day and 40 mg/day doses of istradefylline for reducing the mean total hours of awake time per day spent in the OFF state in patients with Parkinson's disease (PD) treated with levodopa/dopa-decarboxylase inhibitor.Last Visit

Secondary

MeasureTime frame
To evaluate the efficacy of 20 mg/day and 40 mg/day doses of istradefylline for reducing the mean percentage of awake time per day spent in the OFF state.Every Visit
To evaluate mean change in the total hours and the percentage of awake time per day spent in the ON state (without dyskinesia, with dyskinesia, with non-troublesome dyskinesia, and with troublesome dyskinesia).Every Visit
To evaluate the change in Unified Parkinson's Disease Rating Scale (UPDRS).Every Visit
To evaluate change in the Clinical Global Impression - Improvement scale (CGI-I).Visit 4 and Last Visit
To evaluate the safety of 20 mg/day and 40mg/day doses of istradefyllineEvery Visit

Countries

Japan

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026