Will the EMA keep PTC's failed/spurned ataluren on the market for Duchenne MD?

Now that the FDA has put its "Return to Sender" stamp on PTC Therapeutics' application for its Duchenne muscular dystrophy drug ataluren (Translarna), one of the big questions that looms over the biotech is whether the EMA will jerk its surprising conditional approval of the drug.

A spokesperson for the European agency tells FierceBiotech that the Committee for Medicinal Products for Human Use (CHMP) is planning a new assessment of the drug, but doesn't have a timeline to offer.

Simos Simeonides, a biotech analyst at RBC Capital, was left skeptical about PTC's chances at the FDA. After all, he noted this week, PTC's drug had failed a Phase III study that was designed to confirm a positive signal extracted from a subset of patients in a midstage study--and it flopped. Given the FDA's rough treatment of rivals like BioMarin ($BMRN) and Sarepta ($SRPT), as well as its refuse-to-file (RTF) letter to PTC, he gives PTC little chance of progress on the U.S. side of the Atlantic.

The EMA has the next word on the subject, he adds, and it is "a toss-up."

"PTCT management's view of the agreement with EMA is that all they had to do is 'conduct a Phase III study,' i.e. not a Phase III study that met its primary endpoint," notes Simeonidis. "If that is indeed the case, i.e. if all they had to do for the conditional approval to convert to a full approval is just conduct a study (even a failed one), then the Translarna approval in Europe should be OK. Logic would probably suggest that a regulatory agency would not want a drug that has failed to confirm its efficacy on the market. We do however acknowledge the difficulty associated with removing the first drug approved for DMD from the market. We have therefore assigned a 50% probability that Translarna remains on the EU market."

The EMA, which surprised analysts with its conditional approval in the summer of 2014 (which followed an earlier rejection) isn't saying which way it plans to go.

"EMA is aware of the results of this Phase III study which will be assessed by our Committee for Medicinal Products for Human Use in due course," noted a spokesperson for the European agency, responding to a query from FierceBiotech. "We will timely communicate the outcome of its assessment and will inform of any measure which may be taken."

Most biotech stocks have been hammered over the past 5 months, and PTC has joined a growing group that has been forced to endure a severe beating. Its stock plunged more than 60% on the agency's RTF notice, and is now trading at just a fraction of its 12-month high.

PTC isn't commenting on this, for now.

"PTC does not have additional information to provide at this time," a company spokesman tells FierceBiotech via e-mail. "As you know, the company will host its (year end) financial results call next week."