A Study of Istradefylline (KW-6002) for the Treatment of Parkinson's Disease in Patients Taking Levodopa
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ClinicalTrials.gov Identifier: NCT00199355 |
Recruitment Status :
Completed
First Posted : September 20, 2005
Last Update Posted : May 23, 2014
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Parkinson's Disease | Drug: Istradefylline (KW-6002) | Phase 2 |
Study Type : | Interventional (Clinical Trial) |
Enrollment : | 75 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Double |
Primary Purpose: | Treatment |
Official Title: | Placebo-Controlled , Double-Blind , Exploratory Study of KW-6002(Istradefylline) in the Treatment of Parkinson's Disease. [Adjunctive Therapy to Levodopa] |
Study Start Date : | April 2005 |
Actual Primary Completion Date : | March 2006 |
Actual Study Completion Date : | March 2006 |

- To establish the efficacy of 20 mg/d and 40mg/d doses of istradefylline for reducing the percentage of OFF time in patients with advanced Parkinson's disease (PD) treated with levodopa/DCI.
- To evaluate the efficacy of 20 mg/d and 40mg/d dose of istradefylline for reducing the total hours of OFF time.
- To evaluate the change in percentage of ON time (without dyskinesia, with dyskinesia, with non-troublesome dyskinesia, and with troublesome dyskinesia).
- To evaluate the change in Unified Parkinson's Disease Rating Scale (UPDRS).
- To evaluate change in the Clinical Global Impression - Improvement scale (CGI-I).
- To evaluate change in the Clinical Global Impression - Severity of Illness scale (CGI-S).
- To evaluate the safety of 20 mg/d and 40mg/d doses of istradefylline.

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Ages Eligible for Study: | 30 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- UK Parkinson's Disease Society (UKPDS) brain bank criteria (Step 1 and 2) for PD.
- PD stages 2-4 in the OFF state for Modified Hoehn and Yahr Scale.
- On levodopa/DCI for at least one year, stable dose in past 4 weeks.
- Currently take at least three doses of levodopa/DCI per day.
- Predictable end of dose wearing off.
- Able to satisfactorily complete Hauser version of a Parkinson's diary.
- Have an average of 120 minutes of OFF time on two 24 hour diaries.
- On a stable regimen of medications being administered within normal therapeutic limits for Parkinson's disease for at least four weeks before randomization.
- Be at least 30 years of age.
Exclusion Criteria:
- Neurosurgical treatment for PD.
- History of psychosis.
- Diagnosis of atypical Parkinsonism or secondary Parkinsonism variant.
- Diagnosis of cancer within 5 years.
- Diagnosis of clinically significant illness of any organ system.
- Mini-mental status examination score of 25 or less.
- Taking any excluded medications.
- History of drug or alcohol abuse or dependence within the past two years.
- History of seizures or neurological malignant syndrome.
- Clinical depression.
- Pregnant or lactating females.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00199355
Japan | |
Tokyo, Japan |
Study Director: | Study Director | Kyowa Kirin Co., Ltd. |
Responsible Party: | Kyowa Kirin Co., Ltd. |
ClinicalTrials.gov Identifier: | NCT00199355 |
Other Study ID Numbers: |
6002-0406 |
First Posted: | September 20, 2005 Key Record Dates |
Last Update Posted: | May 23, 2014 |
Last Verified: | August 2012 |
Parkinson's Disease levodopa end of dose wearing off OFF time |
Parkinson Disease Parkinsonian Disorders Basal Ganglia Diseases Brain Diseases Central Nervous System Diseases Nervous System Diseases Movement Disorders Neurodegenerative Diseases |
Istradefylline Adenosine A2 Receptor Antagonists Purinergic P1 Receptor Antagonists Purinergic Antagonists Purinergic Agents Neurotransmitter Agents Molecular Mechanisms of Pharmacological Action Physiological Effects of Drugs |