The FDA denied the first appeal of a refuse-to-file letter for an NDA filed by PTC Therapeutics for Translarna (ataluren) for the treatment of nonsense mutation Duchenne muscular dystrophy. PTC plans to escalate its appeal to the agency.

The Feb. 22 refuse-to-file letter stated that the application was not sufficiently complete to permit review. PTC is calling for a full review, including an advisory committee meeting allowing clinicians and patient representatives to express their views on Translarna for the treatment of nmDMD. Last month, the FDA approved Sarepta Therapeutics’ eteplirsen for Duchenne muscular dystrophy after public pressure from patient advocates, as well as members of Congress, and over objections from some FDA reviewers.

Translarna was approved in nmDMD in the European Union in 2014, but is subject to an annual review process. Recently, the European Medicines Agency’s Committee for Medicinal Products for Human Use officially requested supplemental information on the overall risk-benefit profile of Translarna, as well as the design and conduct of an additional clinical trial.