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Kyowa Pharmaceutical Suspends Istradfeylline Development

On Friday, May 2, Kyowa Pharmaceutical, Inc., issued a letter about the suspension of the development of istradfeylline in North America. This letter was issued in response to a study published on the same day in the journal, Neurology, in which people with Parkinson's taking the experimental medication had shown improvement in what is known as "off times" - the side effects that occur when the gold-standard Parkinson's medication, levodopa, wears off. To see details of this study, please read below Kyowa's following letter or click here.

On behalf of Kyowa Pharmaceutical Inc., I would like to thank you for your interest in the istradefylline (KW-6002) program, and I want to inform you of a change in the clinical development plan.

On February 25, 2008, Kyowa received a “Not Approvable” letter from the U.S. Food and Drug Administration (FDA) for istradefylline and subsequently had discussions with the FDA about options for further development. After reviewing these options, Kyowa has decided to suspend development of istradefylline in North America at this time. This decision was not related to any safety issues concerning istradefylline.

This has been a very difficult decision for Kyowa. As always, we will keep you updated on our progress. I would like to extend our deepest thanks for your interest and ongoing support.

We understand that you may have questions and concerns. If so, please contact Kyowa Pharmaceuticals at 609-919-1100.


Satoshi Nakanishi, PhD President Kyowa Pharmaceutical, Inc.

Drug May Cut Tremors Associated With Parkinson's
(HealthDay News)

A new drug may help people with Parkinson's disease combat the tics, spasms and tremors they experience when their main medications wear off, a new study suggests.

Istradfeylline works by helping nerve and brain signals bypass the damaged dopamine system in the brain that leads to Parkinson's. A study of 395 Parkinson's patients on levodopa, a popular Parkinson's drug, found those using istradefylline experienced 24 percent less "off" time, defined as when the physical symptoms appear after levodopa wears off. A group of those studied who took a placebo showed a 10 percent decrease in "off" time.

"These results suggest that istradefylline is effective as an add-on therapy to other drugs that treat symptoms of Parkinson's disease. More importantly, this medication seems to improve 'off' time in a population in which more than 90 percent of patients are already being treated with two or more drugs," study author Dr. Mark Stacy, of Duke University Medical Center in Durham, N.C., said in a prepared statement.

The findings, published in the June 3 issue of Neurology, may not mean relief is coming soon for Parkinson's sufferers, at least in the United States. In March, the U.S. Food and Drug Administration refused to approve the drug, calling evidence of its effectiveness insufficient. The drug's manufacturer, Kyowa Pharmaceuticals Inc., has suspended development of istradefylline in North America.

The study was supported by Kyowa Pharmaceutical. Istradefylline is a novel drug approach to Parkinson's.

The disease is usually treated with medications that work on dopamine, but their effectiveness wears off after time. Istradefylline appears to connect with receptors other than dopamine to open communication with the brain.

"Istradefylline and other agents in the same class that work in a different area of the brain are an important step forward when treating patients who experience this wearing off phenomenon and side effects related to dopaminergic drugs," Stacy said.

Source Date: Jun 03 2008
Source Publication: HealthDay News
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