Sarepta Therapeutics' chief Doug Ingram has come out against accusations that the FDA is biased against the company after its recent drug rejection but offered no timing on when the agency's concerns will be fixed.
Despite not being directly mentioned in its third-quarter press release Thursday night, Ingram did address the FDA’s complete response letter (CRL) to its second Duchenne muscular dystrophy (DMD) hopeful golodirsen right off the bat in his call to analysts and journalists.
He said: “I must also acknowledge what we all know, that we had a setback in the third quarter. And rather than baring it among or after a discussion of our successes, I will begin by commenting our CRL disappointment that occurred in August.
“Having worked diligently on our submission for VYONDYS 53, the generic name for golodirsen for well over a year, and based on all of our interactions with the division of neurology products, we were very confident that we would obtain an approval on our PDUFA date, which was August 19.
“Instead, as you know we were surprised to have received a complete response letter, also known as the CRL, signed by the Office of Drug Evaluation I. Our disappointed extends beyond Sarepta to the 8% of exon 53 amenable DMD patients in the United States to generate every day, while they await access to this therapy.”
Ingram said that the biotech will now “work with the agency to address the reasons for the CRL and to turn in a pathway for a potential approval, if one is possible,” but offered no prediction on outcome or on timing, or to provide interim views during the process.
“However, I will provide an update to the patient, physician and investment communities, once we have definitive clarity on the outcome of those discussions.”
The FDA rejected the New Drug Application for golodirsen, the follow-up to Exondys 51, Sarepta’s first treatment for DMD, in the summer over worries over the risk of infection linked to intravenous infusion ports—devices placed just under the skin to give doctors access to a vein—and kidney toxicity seen in animal studies.
Like Exondys 51, golodirsen is designed to treat a group of Duchenne patients with a certain type of mutation. Exondys 51 works for about 13% of DMD patients—those whose disease is amenable to exon 51 skipping. If approved, golodirsen would offer treatment to patients with a mutation in exon 53—about 8% of the DMD population.
Sarepta has a bullish following from a vocal set of investors, who have raised concerns that the FDA may have rejected this drug because of the questionable approval it got for its first DMD drug, Exondys 51, back in 2016.
There was a lot of hand-wringing from the FDA internally about whether this met the clinical parameters needed for a regulatory green light, and some believe the CRL for Vyondys 53 has come as “payback" for Exondys 51.
Ingram rejected the idea: “To those may believe that the CRL suggest some sort of bias on behalf of the division of neurology towards Sarepta, I would unequivocally and emphatically disagree. Let me reiterate that I remain convinced that we were treated very fairly and professionally by the division of neurology.”
He added that the CRL does have implications beyond Vyondys 53, notably for its next planned submission for PMO casimersen. “As they are closely related, we will await clarity on the Vyondys matter before we submit for casimersen in the United States. But let me disabuse anyone who might have concerns.”
He added, however, that the CRL “does not have any read through to our microdystrophin gene therapy program. The CRL involved two safety signals in connection with an application for accelerated approval. Our microdystrophin program is overseen by a different part of the FDA, Sedar, and we are not seeking accelerated approval there. There is simply no overlap in either substance or personnel.”
In a nod to the vocal investors, he also said that the noises around “applying external pressure to bring this therapy a lot faster” onto the market will not be coming from him.
“I have no intention of doing either of those things,” he said. “If we can win the day with this therapy and with this issue, we will have done so on the size and on the regulation and in collaborative evidence-based discussions with our reviewers at the FDA.”
Sarepta dipped slightly in the red by 0.2% after hours last night.