Jazz Pharmaceuticals' sodium oxybate (JZP-6) demonstrated statistically significant and clinically meaningful improvement in pain and the core symptoms associated with fibromyalgia, according to phase-III data presented last week at the 2009 Associated Professional Sleep Societies meeting in Seattle, Washington. These data have not been evaluated by the FDA or other regulatory authorities for use of sodium oxybate in the treatment of fibromyalgia.

Widespread chronic pain is the hallmark of fibromyalgia, but the vast majority of patients are also affected by a broader constellation of symptoms, including fatigue, sleep disturbances, cognitive dysfunction, and impaired physical function.

"The data showed that sodium oxybate improves the key symptoms of fibromyalgia: pain, fatigue, and sleep disturbances," said Dr Todd Swick, one of the study's investigators and medical director of the Houston Sleep Center and Assistant Clinical professor of Neurology at the University of Texas-Houston School of Medicine. "Millions of people are diagnosed with fibromyalgia and there is a continuing unmet need for therapies that address the constellation of symptoms that can have a significant impact on patients' quality of life."

The 14-week randomized, double-blind, placebo-controlled study included 548 adult patients with fibromyalgia randomized to one of three treatment arms: sodium oxybate 4.5 g/night, sodium oxybate 6 g/night or placebo. The primary outcome measure was the proportion of patients who achieved at least 30 per cent reduction in pain from baseline to endpoint based on the Pain Visual Analog Scale (VAS).

At three months, 54.2 per cent (p<0.001) of patients treated with sodium oxybate 4.5 g/night and 58.5 per cent (p<0.001) of patients treated with sodium oxybate 6 g/night showed significantly greater reduction in pain as measured by at least a 30 per cent improvement in baseline pain VAS score, compared with 35.2 per cent of patients taking placebo using Last Observation Carried Forward analysis.

Jazz Pharmaceuticals has completed its second phase-III clinical trial of JZP-6 and expects to announce top-line results from this study around mid-2009. Assuming positive results for the second study, the company anticipates submitting a New Drug Application for sodium oxybate for the treatment of fibromyalgia to the US Food and Drug Administration by the end of 2009. UCB anticipates filing in the EU shortly after. UCB has the exclusive marketing and distribution rights to sodium oxybate for fibromyalgia in Europe and some other countries outside North America and will manage registrations accordingly.

Sodium oxybate is the sodium salt form of gamma-hydroxybutyrate, an endogenous neurotransmitter and metabolite of GABA.

Jazz Pharma is a specialty pharmaceutical company that identifies, develops and commercializes innovative treatments for important, underserved markets in neurology and psychiatry.