OFF-Time - time when the medication is not working to its full potential and symptoms are not well controlled. This can be predictable such as wearing off between doses when symptoms return at the end of one dose before the next dose is taken; or this can be unpredictable where medication suddenly loses its effect or when a particular dose of medication does not take effect.
A 12-week Randomized Study to Evaluate Oral Istradefylline in Subjects With Moderate to Severe Parkinson's Disease (KW-6002)
Purpose: To assess the efficacy and safety of oral Istradefylline (KW-6002) in patients with moderate to severe Parkinson's Disease who are already on Levodopa/Carbidopa or Levodopa/Benserazide therapy.
Duration: 12 weeks
Study design: Randomized, double-blind, placebo-controlled
30 years of age or older.
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.
Subjects on apomorphine and/or dopamine receptor antagonists or direct gastrointestinal levodopa infusion.
Subject who have had neurosurgical operation for PD.
Subjects who smoke > 5 cigarettes/day