UCB has suffered a setback with the news that European regulators have turned down Xyrem as a treatment for fibromyalgia.

The Belgian firm, which in-licensed the drug from Jazz Pharmaceuticals, currently markets Xyrem (sodium oxybate) in the European Union for the treatment of narcolepsy with cataplexy.However it has now been informed by the Committee for Medicinal Products for Human Use of the European Medicines Agency informed UCB that the treatment will not be recommended as a treatment for fibromyalgia.

Iris Loew-Friedrich, chief medical officer at UCB, said that "upon discussions and following oral explanation with the CHMP, we have to accept that Xyrem in fibromyalgia syndrome will not be recommended for approval in the EU near-term". She added that the firm is very disappointed with the decision given the significant unmet medical need "and the consistently positive Phase III clinical trials with Xyrem in the indication".

No medication has been approved in Europe to date for the treatment of fibromyalgia. and Jazz' bid to get approval for Xyrem in this indication also failed spectacularly last October. The US Food and Drug Administration sent the company a complete response letter and demanded additional clinical studies and more information about ensuring safe use.

Distribution of Xyrem is heavily restricted and is classed as a controlled substance in the USA because of its potential for abuse. Illegal forms of the active ingredient, the sedative gamma hydroxybutyrate or GHB, have been cited in cases of date rape.