Approval in U.S. follows clearance of potassium-channel opener by European Commission in March.
Valeant and its global licensee GlaxoSmithKline (GSK) reported FDA approval of Potiga™ (ezogabine/retigabin, trademarked Trobalt™ outside the U.S.), for use in the adjunctive treatment of partial-onset seizures in patients aged 18 years and over. Clearance of Potiga in the U.S. was based on data from three controlled studies in 1,239 patients, which showed that the drug significantly reduced the frequency of seizures from baseline.
The agency has, however, recommended that the potassium-channel opener is scheduled as a controlled substance, and as a result it will not be available until review by the Federal Drug Enforcement Administration has been completed. A risk evaluation and mitigation strategy will also be required to inform prescribers of the risk of treatment-related urinary retention, a side-effect exhibited by some 2% of clinical trials patients treated using the drug.
Trobalt was approved by the European Commission in March 2011 and was granted preliminary approval by the Swiss authorities in December 2010. The drug is separately undergoing Phase II studies in the treatment of pain associated with post-herpatic neuralgia. Valeant and GlaxoSmithKline inked their exclusive worldwide collaboration agreement for the development of ezogabine/retigabine back in 2008. Under terms of the deal Valeant received a $125 million up-front payment from GSK.