FDA experts turn thumbs down on PTC’s wobbly case for its Duchenne MD drug
After a blistering denunciation from the FDA of the data that PTC Therapeutics $PTCT has submitted on behalf of its Duchenne muscular dystrophy drug ataluren, a panel of experts voted overwhelmingly against the drug, concluding that it’s still too early to say definitively whether the drug works or not and asking for some hard data from a new study to lay the question to rest once and for all.
By a vote of 10 to 1, with a patient representative offering the lone show of support, the panel decided to leave any final decisions on this drug until another pivotal trial can be wrapped.
“It seems like the evidence that kept coming out was mostly from post hoc re-examinations of existing trials after the data had been revealed,” noted Aaron Kesselheim of Harvard Medical School. “And I’m concerned about the possibility for whether consciously or subconsciously there are ways that reanalysis of data in that way can be misleading.”
“Even the meta-analysis wasn’t as convincing as it might have been because of it being based on subgroups,” noted Johns Hopkins’ Caleb Alexander. “So I’m not sure…a number of post hoc analyses can replace the confidence provided by a well-controlled randomized trial that meets its primary prespecified endpoints.”
The FDA’s internal review that appeared publicly two days ago slammed PTC for forcing a new examination of ataluren, a drug that has failed two studies for DMD as well as another pivotal shot at cystic fibrosis — which did nothing for its case. The agency has refused to even accept PTC’s application on two earlier occasions, saying the biotech never offered close to enough data to warrant the time and effort.
The same committee offered another negative, though considerably closer, vote against a rival drug from Sarepta. But despite adamant objections from senior staffers, Janet Woodcock weighed in on behalf of eteplirsen and pulled out an accelerated OK. The drug, though, has a label that states explicitly that there’s no solid evidence of efficacy in its favor.
PTC, though, had won an OK in Europe for ataluren with the same data and clearly felt that it would have a shot, helped by a long lineup of patients and their parents who spoke out on behalf of the drug.
They were wrong.
The FDA doesn’t have to follow the panel’s guidance, but given the internal review and the negative vote — along with Woodcock’s absence from the proceedings today — PTC would not seem to stand a chance.