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XenoPort Announces Presentation of New Data for XP21279 at World Parkinson Congress

SANTA CLARA, Calif.--(BUSINESS WIRE)--Sep 28, 2010 - XenoPort, Inc. (Nasdaq:XNPT) announced today that new data from its first clinical trial of XP21279, a Transported Prodrug of L-Dopa, in Parkinson's disease patients will be presented at the upcoming World Parkinson Congress meeting in Glasgow, Scotland.

Data to be presented at the Congress from XenoPort's four-week, Phase 1b, open-label, crossover clinical trial that evaluated ten Parkinson's disease patients with motor fluctuations show that XP21279 (administered with carbidopa) provided a statistically significant reduction in variability of L-Dopa concentration, based on mean absolute percent deviation from average concentrations of L-Dopa, compared to immediate-release Sinemet (L-Dopa/carbidopa) (p<0.05). In addition, compared to Sinemet, treatment with XP21279/carbidopa led to a reduction in average daily “off” time of 2.9 hours per day and an increase in average daily “on” time without troublesome dyskinesia of 2.4 hours per day. The mean time to “on” after the first morning dose of XP21279/carbidopa was 0.95 hour, compared to 0.97 hour for Sinemet. All treatment-emergent adverse events were mild to moderate in intensity.

Ronald W. Barrett, Ph.D., chief executive officer of XenoPort, stated, “This was an exploratory study in Parkinson's disease patients to see if XP21279 could provide an improved pharmacokinetic (PK) profile compared to Sinemet, one of the most widely used L-Dopa treatments for Parkinson's disease. We were pleased with the PK results of this study, and while we are cautious in interpreting the improvements in symptoms seen in the trial due its open-label design, the efficacy results were sufficiently encouraging to support our initiation earlier this quarter of a double-blind Phase 2 trial comparing XP21279 to Sinemet. We believe that positive results from the Phase 2 trial could support Phase 3 development of XP21279, with the ultimate goal of providing an improved dopamine replacement therapy for those Parkinson's patients who continue to suffer from motor fluctuations while taking currently available oral medicines.”

About XP21279

XP21279 is a patented new chemical entity that is a Transported Prodrug of L-Dopa, also known as levodopa. XP21279 is designed to utilize natural nutrient transport mechanisms located throughout the length of the gastrointestinal (GI) tract, enabling rapid absorption and conversion to L-Dopa by the body's naturally occurring enzymes. Because XP21279 is designed to be well absorbed from the lower GI tract, it has been formulated for sustained release and has been shown to reduce fluctuations of L-Dopa levels in the bloodstream compared to Sinemet. XenoPort has initiated a Phase 2 clinical trial to evaluate the efficacy, safety and pharmacokinetics of a new bi-layer formulation of sustained release XP21279 and carbidopa in patients with Parkinson's disease.

About Parkinson's Disease

Parkinson's disease is a motor system disorder that results from the loss of dopamine-producing nerve cells in the brain. Dopamine is a chemical that is naturally produced by the body. It is responsible for smooth, coordinated function of the body's muscles and movement. When approximately 80% of dopamine-producing cells are damaged, the symptoms of Parkinson's disease appear. The primary symptoms of Parkinson's disease are tremor or shaking, slowness of movement, rigidity or stiffness and difficulty with balance. The Parkinson's Disease Foundation estimates that as many as one million individuals in the United States live with Parkinson's disease.

About XenoPort

XenoPort, Inc. is a biopharmaceutical company focused on developing a portfolio of internally discovered product candidates that utilize the body's natural nutrient transport mechanisms to improve the therapeutic benefits of existing drugs. XenoPort is collaborating with Astellas Pharma Inc. and GlaxoSmithKline to develop and commercialize XP13512, its lead product candidate. XenoPort's product candidates are being studied for the potential treatment of restless legs syndrome, gastroesophageal reflux disease, neuropathic pain, spasticity and Parkinson's disease. To learn more about XenoPort, please visit the web site at

Forward-Looking Statements

This press release contains “forward-looking” statements, including, without limitation, all statements related to XenoPort's future clinical development and trials of XP21279 and the results thereof; the therapeutic and commercial potential of XP21279; and the suitability of XP21279 as a treatment for patients with Parkinson's disease. Any statements contained in this press release that are not statements of historical fact may be deemed to be forward-looking statements. Words such as “believe,” “will,” “could,” “encouraging,” “goal,” “potential,” and similar expressions are intended to identify forward-looking statements. These forward-looking statements are based upon XenoPort's current expectations. Forward-looking statements involve risks and uncertainties. XenoPort's actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of these risks and uncertainties, which include, without limitation, the ability of XenoPort to successfully conduct clinical trials for XP21279 and the uncertainty of the timing and results thereof; and the uncertain therapeutic and commercial value of XP21279. These and other risk factors are discussed under the heading “Risk Factors” in XenoPort's Quarterly Report on Form 10-Q for the quarter ended June 30, 2010, filed with the Securities and Exchange Commission on August 6, 2010. XenoPort expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in the company's expectations with regard thereto or any change in events, conditions or circumstances on which any such statements are based.

XenoPort and Transported Prodrug are trademarks of XenoPort, Inc.

Source code: XNPT2C


Contact: XenoPort, Inc.
Jackie Cossmon, 408-616-7220


Posted: September 2010