Stocks Sarepta Therapeutics More than 30% fell sharply on Friday as the future of approved gene therapy treatments became at risk.
The Food and Drug Administration requires that the company voluntarily suspend all delivery of treatments.
Salepta told CNBC that she had not heard from the FDA.
Separately, FDA committee member Marty McCurry told Bloomberg News that the agency is considering whether the company’s gene therapy should remain in the market.
The FDA is investigating the deaths of two patients associated with Elevidi, which accounts for more than half of Salepta’s net product revenue. The company also reported a third death linked to another experimental gene therapy.
Elevidys is in controversy even before it was approved. Gene therapy has not yet been clearly demonstrated that it can benefit people with Duchenne muscular dystrophy.
People with illness eventually lose the ability to walk, and most die by their early 20s. In other words, there is a huge need for treatment that is not met. The 2023 FDA originally granted Elevidys conditional approval for patients only between the ages of 4 and 5, the most profitable group in clinical trials.
The following year, the agency fully approved treatment for patients over the age of four, and accelerated approval for patients 4 and beyond whom they could not walk any more. The latter decision was particularly controversial as there is little evidence that the disease can help people who are already very advanced.
Additionally, Erebidis failed to meet its target in the Phase 3 trial, but the company claimed the drug had shown promise to other metrics in the study. The head of the FDA’s Biological Evaluation and Research Center agreed to the assessment of Salepta and rejected the FDA staff to expand the approval of Erebidi.
Earlier this year, Salepta revealed that two teenage boys died of liver failure after receiving Elevidi. Then, this week, reports emerged that another person died after another trial investigated another trial of salepta gene therapy because of another disease.
The two treatments are different, but they share the same birth method, which raises safety concerns about Erebidi. According to BMO analyst Kostas Biliouris, Elevidys’ safety is particularly important given the uncertain benefits.
For example, Novartis’ gene therapy for spinal muscular atrophy also caused liver toxicity and death, but the benefits of that treatment are clear.
“That’s why death here is so important to Zorgensa,” Biliouris said.
And Sorgensma is just one of many drugs for large companies like Novartis. For Salepta, Erebidi is everything.
Executives this week tried to reassure investors. Even if it is still possible to treat patients who can walk, if no deaths are reported, treatment should bring at least $500 million a year. Last month, Salepta stopped shipping Elevidi to patients who are unable to walk while exploring safer ways to carry out treatment.
The biggest concern for investors at this point is whether the FDA is pulling the drug, Biliouris said. The company’s stock has fallen by more than 87% this year.
“If the FDA pulled Elevidys out of the market, the Salepta is complete,” he says.
Jennifer Hand, whose son was diagnosed with Duchenne muscular dystrophy in the second half of 2020, said it was “courtly” that other patients do not have the treatment options to resort to in the event that Erevidi’s shipment is suspended.
Her son, Charlie, was administered alongside Elevidi in 2022 as part of Salepta’s late stage trial, and found improvements in six to 12 months, including increased stamina and more fluid movements. The drug also relieves the obvious symptoms of a condition called the Gowers sign.
She said her son was “fully stable” three years after his dose. Hand said Charlie was aware of the liver toxicity risk before he signed up for the trial.
“There’s no luxury of not taking risks,” Hand said. “Even at risk, families who deal with the disease will do anything to do.”
“Every family members need to make this leap with this drug and be able to see potential benefits,” she added.
