Date Rape Drug As Cure For Muscle Pain

The US Food and Drug Administration (FDA) might have moved one step closer to approving Xyrem (sodium oxybate), also known as a date rape drug, for treatment of fibromyalgia.

The agency posted its review online, saying the drug manufactured by Jazz effectively treated pain from fibromyalgia in two company-run studies. It has, however, raised safety concerns over the controversial drug.

Fibromyalgia is characterized by widespread muscle pain and other symptoms including fatigue, headache and depression.

The American College of Rheumatology estimates that between 6 million and 12 million people in the U.S. have fibromyalgia, more than 80 percent of them women.

Jazz Pharmaceuticals, based in Palo Alto, Calif., already markets Xyrem as a treatment for narcolepsy, excessive sleepiness. The FDA approved Xyrem for narcolepsy patients in 2002 as an orphan drug, a category used for medications that treat conditions affecting 200,000 or fewer people.

Xyrem is considered a "controlled substance," by the U.S. drug enforcement regulators, and patients and doctors prescribing the drug must register with the government. Between 2002 and 2009, the FDA identified just five cases of misuse or abuse of the drug

Gamma hydroxybutyrate, a sedative also known as GHB, is the active ingredient in Xyrem. Illegal forms of GHB have been used as club drugs and are implicated in date rapes, according to the National Institute on Drug Abuse.

The GHB abuse has been associated with some important central nervous system (CNS) adverse events (including death). Even at recommended doses, use has been associated with confusion, depression and other neuropsychiatric events. Reports of respiratory depression occurred in clinical trials. Almost all of the patients who received sodium oxybate during clinical trials were receiving CNS stimulants.

Important CNS adverse events associated with abuse of GHB include seizure, respiratory depression and profound decreases in level of consciousness, with instances of coma and death.

The Drug Enforcement Administration classifies Xyrem as a schedule III controlled substance, meaning distribution is restricted because of the potential for abuse.

Xyrem is mailed to patients through a central pharmacy rather than sold in retail drugstores. A registry tracks doctors who prescribe the drug and patients who use it. Xyrem also comes with a black box warning, the FDA's strictest caution, alerting patients that misuse can lead to seizures, coma and death.

FDA reviewers cautioned that an approval of Xyrem for fibromyalgia would greatly expand the drug's patient population, making it harder to control. Drug reviewers recommended a strict distribution and monitoring plan "to positively identify and document cases of abuse, misuse, diversion and overdose."

On Thursday a panel of outside FDA experts will weigh in on whether the drug should be approved for fibromyalgia. The FDA is not required to follow the group's advice, though it often does.

"The fact that the FDA didn't raise a whole lot of questions on the side effects is a major positive," Difei Yang, an analyst with San Diego-based Capstone Investments Inc., said in a telephone interview. "I think eventually the FDA is going to approve the drug; it's just a matter of how restrictive the Risk Evaluation and Mitigation Strategies (REMS) program will have to be to mitigate the risk."

Jazz expects the FDA to complete its review of the drug by Oct. 11. The company has proposed selling it under the name Rekinla.



Source: Medindia