Jazz Pharmaceuticals Fibromyalgia Potential Rejected by FDA

Jazz Pharmaceuticals (JAZZ) shares slumped more than 5% in premarket trading Monday after the Palo Alto, Calif.-based company announced that, as expected, the Food and Drug Administration had denied approval for its potential fibromyalgia drug JZP-6 (sodium oxybate).

In its complete response letter, the FDA indicated "the need for additional clinical studies, the appropriate patient population, methods for ensuring safe use, and the proposed REMS, concentration and trade name for the product," Jazz said in a statement.

"We have requested a meeting with FDA in order to discuss and clarify the contents of the CRL and will then evaluate our next steps for JZP-6," said Chairman and CEO Bruce Cozadd "We continue to believe there is a significant unmet medical need among fibromyalgia patients that could be met by JZP-6 if it were approved by FDA." Approval of the drug for fibromyalgia would have increased Jazz's sales dramatically.

Back in August, an FDA advisory panel overwhelmingly voted to recommend the FDA reject the fibromyalgia drug. JZP-6 contains sodium oxybate, which is a federally controlled substance more widely known as GHB. While Jazz sells JZP-6 under the name Xyrem to treat narcolepsy, sodium oxybate is also sold illegally both as a "club drug" and a date rape drug. As a sedative, in high doses it can cause death. The panelists said the risk/benefit analysis did not warrant approval, and were concerned about the greater potential for abuse wider approval would bring.

Fibromyalgia is a poorly understood condition that causes muscle pain and fatigue. The disorder is believed to affect 2% to 4% of the population, or about 5 million Americans, mostly women. Traditionally, it has been treated with a combination of painkillers and antidepressants, according to the FDA.