After the FDA revoked Sarepta Therapeutics’ platform designation in July, Krystal Biotech is “poised to be the first major beneficiary” of this program, according to analysts at William Blair.
The FDA has handed out its second platform technology designation to Krystal Biotech for the company’s non-replicating HSV-1 viral vector, which it uses to deliver its gene therapies.
In a note to investors on Tuesday, analysts at William Blair wrote that Krystal is “poised to be the first major beneficiary” of the agency’s platform designation program. The first award was given in June to Sarepta Therapeutics for its adeno-associated virus vector platform. But after a series of deaths linked to the platform, the FDA revoked the designation a month later.
“We view the FDA’s platform technology designation as validating Krystal’s HSV-1 vector platform and cross-program utility,” William Blair said.
Krystal on Tuesday said it plans to leverage the FDA’s designation for its redosable eye drop gene therapy KB801, being developed for neurotropic keratitis, a rare corneal disease that leads to eye injuries. The asset is currently in Phase I/II development.
The FDA awards its platform technology designation to companies that use a certain “well-understood and reproducible technology,” such as a method of delivery, as an “essential” part of its drugs, according to a May 2024 draft guidance document for the program. The platform technology must also be applicable to and used by more than one of the company’s assets while standardizing the production or manufacturing of these products.
The platform technology designation “is intended to provide efficiencies” in the drug development and regulatory review processes for products that use the technology, Krystal said on Tuesday. The award also allows drug sponsors to use manufacturing and nonclinical safety data from previous products—as long as they use the same technology—in future submissions to the FDA.
Krystal’s HSV-1 technology uses a replication-deficient version of the herpes simplex virus type 1, according to the biotech’s website. The vector takes advantage of HSV-1’s natural characteristics, such as a high payload and ability to evade the immune system, with the aim of minimizing toxicities.
Krystal’s only approved product, the gene therapy Vyjuvek, approved in 2023 as a topical gel for treating wounds in patients with dystrophic epidermolysis bullosa, uses this HSV-1 platform. “Interestingly, Vyjuvek is administered topically to the skin,” William Blair wrote, while KB801 is formulated as an eye drop.
That the FDA nevertheless granted its platform designation to Krystal suggests that the agency “viewed Krystal’s HSV-1 vector as likely having reproducible efficacy across administration methodologies,” the analysts added.
