The Food and Drug Administration has decided that the sedative-hypnotic drug sodium oxybate cannot be approved for treatment of fibromyalgia, based on the information currently included in the approval application, the manufacturer has announced.
The statement issued by Jazz Pharmaceuticals noted that the FDA's “complete response letter” said the new drug application for sodium oxybate cannot be approved “in its present form” and cited the need for more clinical studies. The FDA's letter also discusses the proposed Risk Evaluation and Mitigation Strategy (REMS), as well as the concentration and trade name for sodium oxybate, according to Jazz. Other topics discussed in the letter include the need for methods to ensure safe use of the drug, the sodium salt of gamma hydroxybutyrate, an endogenous neurotransmitter synthesized from gamma aminobutyric acid, which is also known as the “date rape” drug for its potent sedative effects.
It is the FDA's practice to send complete response letters to sponsors of new drug applications when there are concerns about whether the drug should be approved and to outline information needed to complete the approval process. The agency does not comment on products under review, and therefore does not release information on these letters.
The concerns that the Jazz statement said were outlined in the letter reflect those expressed by members of two FDA advisory panels at a summer meeting held to review the data on sodium oxybate for the fibromyalgia indication. At the meeting, most of the panelists voted against recommending approval, citing the lack of long-term data and other concerns regarding the drug – including its potential for illicit use.
The drug's only approved indication is for the treatment of narcolepsy, a fairly uncommon condition. Were sodium oxybate to be approved for fibromyalgia, which is more common, it is possible that the drug would be more likely to be misused because it would be present in more family medicine cabinets.
Sodium oxybate also is the active ingredient in Xyrem, which is approved for treating excessive daytime sleepiness and cataplexy in adults with narcolepsy.
The Jazz statement says that the company has requested a meeting with the FDA to discuss the complete response letter, and will then evaluate the next steps for the drug.