PTC Therapeutics' appeal on Translarna rejected by FDA unit

US drugmaker PTC Therapeutics (Nasdaq: PTCT) announced today that, at the end of last week, the US Food and Drug Administration’s Office of Drug Evaluation I (ODE-I) denied the company's first appeal of the refuse to file letter issued by the FDA's Division of Neurological Products (DNP) on February 22, 2016 regarding PTC's New Drug Application for Translarna (ataluren) for the treatment of nonsense mutation Duchenne muscular dystrophy (nmDMD).

The company intends to escalate its appeal to the next supervisory level of the FDA. This is an iterative process and the company anticipates that multiple cycles of appeals to progressively higher levels of the FDA may be required. Nevertheless, the company’s shares plummeted 29.2% to $9.41 on the news.

PTC continues to assert that a proper assessment of the data and analyses from multiple clinical studies, including two of the largest placebo-controlled trials ever conducted in DMD, can only be accomplished in the context of a full and fair review by the FDA. This would include an advisory committee meeting that allows clinical experts and representatives of the patient community to express their views on Translarna for the treatment of nmDMD. The company believes that Translarna is the only therapy in clinical development designed to target the underlying cause of nmDMD. In addition, a favorable safety profile has been consistently demonstrated in PTC's clinical trials, which have enrolled over 1,000 individuals to date.