Abeona works with FDA to improve EB-101 application for RDEB
Developer hopes to maximize chances of approval for cell therapy
Abeona Therapeutics has been working with the U.S. Food and Drug Administration (FDA) ahead of its planned submission of a biologics license application (BLA) for EB-101, with an aim of maximizing the chances of having its cell therapy approved as a treatment for recessive dystrophic epidermolysis bullosa (RDEB).
The FDA has provided “critical” feedback about manufacturing data that will be required as Abeona prepares to submit the BLA, the company said in a press release updating its plans for the therapy’s development.
Specifically, according to Abeona, the FDA is seeking to confirm that the viral carrier — called a retroviral vector (RVV) — used to help the therapy be taken up by patients’ skin cells is the same regardless of whether it’s manufactured by the company in-house or externally at Indiana University.
RVVs from both sources were used in clinical studies of EB-101, so it’s important to ensure their safety and efficacy profiles are similar, according to the company.
Abeona seeks to push back FDA meeting on EB-101
To allow the agency time to review the additional data — which Abeona says it has the necessary material to quickly generate — the company has requested that a planned pre-BLA meeting with the FDA be pushed to August. Abeona will submit the BLA in the months after that meeting.
By having discussions with the regulatory agency prior to submission, the company is able to address FDA concerns and maximize the chances that the therapy will be approved.
“Gaining alignment with the FDA on the RVV comparability package is a very important de-risking milestone for our BLA submission,” said Vish Seshadri, CEO of Abeona.
RDEB is caused by mutations in the COL7A1 gene, which is responsible for producing part of a protein needed for the skin’s structural integrity. That protein, called type VII collagen, is lacking in people with RDEB. As such, patients have fragile skin that easily blisters and tears. This can lead to chronic, open wounds that don’t easily heal.
EB-101 is a gene-corrected cell therapy that aims to restore more normal production of type VII collagen in RDEB patients’ wounds.
With the treatment, a person’s own skin cells are obtained and grown in the lab, where they are genetically modified to carry a healthy version of COL7A1. The RVV helps to deliver the genetic material into the patients’ cells.
The corrected cells are then affixed onto a sheet of keratinocytes — the main cell type found in the skin’s outer layer — and surgically transplanted onto a wound, where the healthy cells are integrated to promote wound healing.
Study found better wound healing with EB-101
Abeona’s BLA will be backed by data from the Phase 3 VIITAL trial (NCT04227106), which enrolled 11 RDEB patients with large, chronic wounds that had not healed for at least six months, and as long as 21 years.
A total of 43 pairs of wounds across these 11 patients were included in the trial’s main analysis. For each pair, one wound was randomly assigned to be treated with EB-101, while the other was left untreated.
One of the trial’s main goals was to assess the proportion of wounds with 50% or greater healing after six months. Results showed that a significantly greater proportion of EB-101-treated wounds — 81.4% — were healed by at least 50% compared with untreated wounds, where only 16.3% met that benchmark.
The other main goal, which was evaluating changes in patient-reported pain, also was met. The individuals given the investigational therapy reported that their pain dropped by a mean of 3.07 points on the 10-point Wong-Baker FACES scale, compared with a 0.9 point reduction for untreated wounds.
Additional trial analyses indicated that the benefits of EB-101 were observed even sooner than six months, with wound healing and pain reductions observed as early as week six.
Moreover, patients reported that EB-101 led to significant reductions in itch and blistering relative to untreated wounds. Caregiver-reported outcomes related to wound care and impression of wound pain showed trends toward improvement.
EB-101 was well tolerated, with no serious treatment-related side effects observed.
The therapy has earned orphan drug and rare pediatric disease designations in the U.S., which offer incentives to accelerate the development of treatments toward regulatory approval.
Should the FDA agree to review Abeona’s BLA application, the company expects that it will be granted a priority review voucher, one of the incentives of the rare pediatric disease designation. Such vouchers can be used for a faster review of a subsequent application of another treatment, or be transferred to another company.
About the Author
