Should the pharmaceutical drug Xyrem® (sodium oxybate) become the first pharmaceutical drug approved by the FDA and other agencies for treatment of Fibromyalgia symptoms, its marketers are poised to commercialize the drug for this purpose on a global scale.
Currently, a phase III trial of the drug, with sites in 20 states and 33 locations, is enrolling Fibromyalgia patients as subjects for 21-week participation periods, according to ClinicalTrials.gov. No recruitment closing date has been announced.
This trial, sponsored by Palo Alto, California-based Jazz Pharmaceuticals, marketer of Xyrem® in the United States, will test the drug's safety and effectiveness for treatment of Fibromyalgia patients. As a phase III trial, it will involve a larger group of subjects – in this case a projected total of 525 – and will focus on monitoring side effects and collecting data on requirements for safe use.
Currently, Xyrem® is FDA approved, as indicated in its labeling, to treat “cataplexy” – or loss of muscle tone/muscle slackening – in narcolepsy patients. Narcolepsy is a chronic neurological disease characterized by “excessive daytime sleepiness and fragmented nighttime sleep” as well as cataplexy. Xyrem®’s licensed marketer in EU countries – Euronext Brussels (UCB) – has also applied for approval to market the drug in the EU for “all symptoms of narcolepsy,” including the sleep problems.
Possible benefits for FM patients. A previous U.S.-based trial of sodium oxybate, a “central nervous system depressant,” for an “off-label” application with Fibromyalgia patients indicated it “significantly improved patients’ self-reported perceptions of their own pain and enhanced the quality of their sleep,” according to researchers at the Oregon Health Sciences University in Portland, who introduced their finding November 22, 2005 at an American College of Rheumatology Scientific Meeting. See the article “Dream Catchers: Researchers Bring Hope to Fibromyalgia Syndrome” at http://www.immunesupport.com/library/showarticle.cfm/id/7130
(Physicians may prescribe drugs for purposes other than those indicated on their label. This is termed “off-label” prescribing.)
“If and when” Xyrem® is approved as a drug specifically for the treatment of Fibromyalgia Syndrome, as of October 3, 2006 Jazz Pharmaceuticals agreed that UCB will have the right to market the drug for this indication in a total of 54 countries.
Notably, sodium oxybate (gamma Hydroxybutyric Acid) is listed as a “Schedule III” drug in the United States, under the Controlled Substances Act. By definition, this is a substance that “may lead to moderate or low physical dependence or high psychological dependence.” For information about possible side effects and contraindications, see the Xyrem® package insert (http://www.xyrem.com) – though as we went to press we were unable to pull up this information.
Specifics of the present trial are as follows.
n Official trial title: "A Phase III, Randomized, Double-Blind, Placebo-Controlled, Safety and Efficacy Study of Xyrem® in Subjects With Fibromyalgia."
n To be included, subjects must be diagnosed with Fibromyalgia in accordance with the American College of Rheumatology criteria, must be 18 years of age or older, and may be male or female.
n Subjects will be excluded if they have a history of rheumatic disease or other disorders that may compromise reliable representation of subjective symptoms. Any other condition that will cause a risk to subjects if they participate in the trial is also a reason for exclusion.
n Total duration for each subject is up to 21 weeks of trial participation. This will include a screening and withdrawal/washout period lasting up to 5 weeks combined, followed by a “baseline” period lasting 1 week, and total treatment duration of 14 weeks, followed by a 1-week safety follow-up post treatment period.
n During the screening and withdrawal/washout period, no study medication will be given; however “rescue medication” acetaminophen (up to 4 grams per day) will be allowed.
n Primary outcomes measures will be: Pain Severity assessed by VAS (Visual Analog Scale); Fibromyalgia Impact Questionnaire; and Patient Global Impression of Change.
For more information and a list of study sites with contact information/links go to http://www.clinicaltrials.gov/ct/show/NCT00371137?order=5