PTC's ataluren flops in another PhIII and an analyst says it's clearly a dud; kill it
PTC Therapeutics has whiffed once again on Translarna (ataluren).
The biotech reported that ataluren, a repeat flop in Duchenne muscular dystrophy, failed a Phase III for nonsense mutation cystic fibrosis on both the primary and secondary endpoints.
Investigators tracked a slight but insignificant advantage for patients in the drug arm of the CF study, noting a better number for lung capacity and the rate of pulmonary exacerbations. But none of it stacked up in a way worth taking to regulators, and the biotech says it will scrap its work in CF and jerk its application for approval in Europe.
The company’s stock $PTCT dropped 20% on the news.
PTC has a long track record of failure in the clinic when it comes to ataluren. A flop in Phase IIb as well as Phase III for DMD, the FDA refused to accept its application for review in early 2016, saying the biotech’s pitch failed to qualify for a review — a rare slapdown from regulators. PTC is now appealing that decision for the second time.
Despite that, though, European officials have allowed the sale of Translarna for Duchenne muscular dystrophy. The European Commission ratified an extension of PTC’s marketing approval in early January as PTC pursues another study to keep its marketing authorization in place. And the biotech expects to earn more than $100 million this year on sales outside the US, backed by a number of patient advocates who believe the drug works, despite the data.
RBC’s Simos Simeonidis said this afternoon that the string of trial failures demonstrate that the drug is clearly a dud and ought to be pulled.
Following this compound’s failure in the ACT DMD trial, which was supposed to be the confirmatory trial (which based on post-hoc analyses from a Phase II trial in DMD that had failed to meet its primary endpoint), we no longer believed this compound worked in CF, and had thus assigned 0% probability of success for it in ACT CF. We now believe there is ample clinical evidence from multiple randomized clinical trials that this is an inactive compound.
“We are disappointed with the outcome of this trial as there are no treatments that target the underlying cause of nonsense mutation cystic fibrosis, one of the most difficult forms to treat,” said Stuart W. Peltz, PhD, chief executive officer of PTC Therapeutics in prepared text. “We are particularly grateful to patients and investigators who participated in our trials. We remain committed to patients receiving ataluren in other indications.”