As expected, regulators in the USA have rejected Jazz Pharmaceuticals' date rape drug-based fibromyalgia treatment, demanding more clinical data and proof of its safety.

The US Food and Drug Administration has sent the company a complete response letter regarding its New Drug Application for JZP-6 (sodium oxybate) for fibromyalgia. The letter "discusses a number of topics", said Jazz, "including the need for additional clinical studies, the appropriate patient population, methods for ensuring safe use and the proposed risk evaluation and mitigation strategies, concentration and trade name (Rekinla) for the product".

Quite a list and in keeping with an FDA advisory committee's 20-2 vote in August against JZP-6. The panel had said that concerns over the potential for abuse and accidental overdose  overshadow the therapeutic benefit of the treatment, which is currently marketed for narcolepsy as Xyrem.

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

How Jazz progresses with JZP-6 is not clear. Chief executive Bruce Cozadd, said "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". He added that "we continue to believe there is a significant unmet medical need among fibromyalgia patients that could be met by JZP-6".