Submission of NDA for Istradefylline(KW-6002), an investigational anti-Parkinson's disease drug

Kyowa Hakko Kogyo Co. has announced that Kyowa Pharmaceutical, Inc., its wholly owned U.S subsidiary, submitted on April 25, 2007 a new drug application (NDA) to the U.S. Food and Drug Administration (FDA) for Istradefylline(KW-6002), its investigational drug for Parkinson's disease.

Parkinson's disease is a progressive neurodegenerative disorder which is characterized by motor symptoms such as slowness of movement, rigidity, tremor and postural instability. The symptoms of this disease result from the progressive degeneration of certain nerve cells located in a specific area in the brain leading to a shortage of the neurotransmitter dopamine. This results in decreased activation of dopamine receptors in the brain which is thought to cause the motor symptoms. The symptoms of Parkinson's disease are treated primarily by dopamine replacement therapy with Levodopa or dopamine agonists. Long term therapy with Levodopa is associated with motor complications such as the development of a shortening response to each dose, which is called "wearing-off phenomenon", and involuntary movements.

Phase II and III clinical studies were conducted with Istradefylline (KW- 6002) in Parkinson's disease patients experiencing "wearing-off phenomenon" on treatment with Levodopa alone or Levodopa administered concomitantly with other Parkinson's disease medications. Based on the clinical efficacy and safety data obtained, the company submitted a NDA for Istradefylline(KW-6002) as adjunctive therapy to levodopa/carbidopa for the treatment of idiopathic Parkinson's disease to improve motor function in patients who experience motor response complications.

Istradefylline(KW-6002) is a novel investigational anti-Parkinson's drug that has a specific antagonistic action on the Adenosine A2A receptor in the brain and is expected to provide benefit to patients with Parkinson's disease.