(Reuters) - PTC Therapeutics Inc’s shares plummeted more than 50 percent on Tuesday, after the U.S. Food and Drug Administration said the company’s marketing application for a muscle disorder drug was insufficient to warrant a review.
The company’s drug, translarna, is being evaluated in patients with Duchenne Muscular Dystrophy (DMD), a progressive degenerative disorder that hampers muscle movement and affects one in 3,600 newborn boys.
Patients with DMD lose their ability to walk as early as age 10 and experience life-threatening lung and heart complications in their late teens and twenties.
There exists no FDA-approved therapy for the condition, and pressure has been mounting on the U.S. health regulator to swiftly approve treatments.
BioMarin Pharmaceutical Inc and Sarepta Therapeutics Inc are developing drugs for DMD, but their treatments target a different subset of patients. The FDA rejected Biomarin’s drug last month.
It remains unclear whether FDA’s letter to PTC was due to an inadequately organized application or insufficient data, analysts said.
However, Oppenheimer analysts said they would not be surprised to see the company resubmitting the application later this year, pushing the U.S. timeline to 2017.
In October, PTC said translarna had failed to meet the main goal in a late-stage study, but data showed that in a sub-group of patients with less advanced DMD, the effect was deemed clinically meaningful.
PTC had also then said it was confident that its entire dataset, including those from previous trials, would be enough to support a U.S. marketing application for translarna, which won conditional European approval in 2014.
Jefferies analyst Gena Wang said she sees a “slim” chance for the drug’s U.S. approval, based on unclear drug mechanism and questionable clinical data.
Translarna generated sales of $21 million in the first three quarters of 2015.
PTC’s shares were down 51.6 percent at a more-than-two-year low of $13.77 on the Nasdaq. Nearly 12.1 million shares traded, over 14 times their 30-day moving average.
Reporting by Rosmi Shaji in Bengaluru; Editing by Don Sebastian and Sriraj Kalluvila