A 12-week Randomized Study to Evaluate Oral Istradefylline in Subjects With Moderate to Severe Parkinson's Disease (KW-6002)

Kyowa Kirin

Status and phase: Completed; Phase 3

Conditions: Idiopathic Parkinson's Disease

Treatments: Drug: Placebo; Drug: Istradefylline 20 mg; Drug: Istradefylline 40 mg

Study type: Interventional

Funder types: Industry

Identifiers

NCT01968031

6002-014

2013-002254-70 (EudraCT Number)

Details and patient eligibility

About

This is a study to assess the efficacy and safety of oral Istradefylline (KW-6002) in patients with moderate to severe Parkinson's Disease. While on this study, participants will continue to take their usual, prescribed, stable regimen of Levodopa/Carbidopa or Levodopa/Benserazide therapy plus adjunct Parkinson's medications. Patients will be randomized 1:1:1 to receive either Istradefylline 20 mg per day, or Istradefylline 40 mg per day or an equivalent placebo. Patients will be treated for a 12 week period to demonstrate the effectiveness of Istradefylline in improving Parkinson's disease symptoms (referred to as improvement in patient OFF time) and that Istradefylline has an acceptable safety profile in this group.

Enrollment: 613 patients

Sex: All

Ages: 30+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• 30 years of age or older.
• UK Parkinson's Disease Society (UKPDS) brain bank criteria (Step 1 and 2) for PD
• PD Stages 2-4 in the ON state for Modified Hoehn and Yahr Scale.
• On levodopa therapy for at least 1 year with beneficial clinical response at the baseline visit
• Taking at least 400mg levodopa combination daily and on stable regimen of any other anti-Parkinsonian drugs (MAO-B, COMT, DA) for at least 2 weeks prior to randomization
• Stable dopaminergic regimen for at least 4 weeks immediately prior to randomization
• Documented end-of-dose wearing-off and levodopa-induced dyskinesia
• Have an average of two hours of OFF time per day

Exclusion criteria

• Subjects on apomorphine and/or dopamine receptor antagonists or direct gastrointestinal levodopa infusion.
• Subject who have had neurosurgical operation for PD
• Subjects taking A2a antagonist, potent CYP3A4 inhibitors, potent CYP34A inducers
• Subjects who smoke > 5 cigarettes/day

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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613 participants in 3 patient groups, including a placebo group

Istradefylline 20 mg/day

Experimental group

Description:

Istradefylline 20 mg and placebo to match istradefylline 40 mg: A daily, oral, double-blind treatment dose of both tablets will be taken in the morning for 12 weeks.

Treatment:

Drug: Istradefylline 20 mg

Drug: Placebo

Istradefylline 40 mg/day

Experimental group

Description:

Istradefylline 40 mg and placebo to match istradefylline 20 mg: A daily, oral, double-blind treatment dose of both tablets will be taken in the morning for 12 weeks.

Treatment:

Drug: Istradefylline 40 mg

Drug: Placebo

Placebo

Placebo Comparator group

Description:

Placebo to match istradefylline 20 mg and placebo to match istradefylline 40 mg: A daily, oral, double-blind treatment dose of both tablets will be taken in the morning for 12 weeks.

Treatment:

Drug: Placebo