Second Gene Therapy for Epidermolysis Bullosa up for Priority Review
Pz-cel has a PDUFA date of May 25, 2024.
The FDA has accepted Abeona Therapeutics’ biologics license application (BLA) for its autologous, gene-corrected epidermal sheet therapy Pz-cel (prademagene zamikeracel; EB-101) with priority review for the potential treatment of recessive dystrophic epidermolysis bullosa (RDEB).1 The FDA has set a Prescription Drug User Fee Act (PDUFA) of May 25, 2024.
“The FDA’s acceptance of our BLA for priority review underscores the high unmet need in RDEB and the potential for pz-cel to provide meaningful benefit to these patients,” Vish Seshadri, chief executive officer, Abeona, said in a statement.1 “We thank the FDA for their commitment and look forward to working with them through the BLA review, with the goal of bringing this therapy to patients as soon as possible.”
Pz-cel is an investigational, autologous, COL7A1 gene-corrected epidermal sheet therapy designed to correct the defect in the COL7A1 gene resulting in the inability to produce Type VII collagen in patients with RDEB. Pz-celuses a retroviral vector to integrate COL7A1 into the dividing target cell genome for long-term gene expression and has been granted Regenerative Medicine Advanced Therapy, Breakthrough Therapy, Orphan Drug and Rare Pediatric Disease designations by the FDA.
Abeona previously submitted its BLA for pz-cel in September 2023 after announcing a positive pre-BLA meeting in August.2,3 During this meeting, Abeona established that the efficacy and safety data seen with pz-cel so far would be enough to support the BLA submission and that retroviral vector manufactured at Abeona and Indiana University appear comparable based on provided data. The FDA requested that the BLA submission include background and data supporting the therapy's potency and identity assays as well as supplemental data relating to chemistry, manufacturing, and controls.
WATCH NOW: Brett Kopelan, MA, on the Future Treatment of Epidermolysis Bullosa With Advanced Therapeutics
Topline data from the phase 3 VIITAL study (NCT04227106) were announced in November that showed the study had met its primary endpoints of achieving over 50% wound healing and a greater magnitude of pain reduction benefit at 6 months after treatment compared to baseline and control wounds.4
“Large chronic RDEB wounds are the toughest to treat and often associated with intense chronic pain that significantly impacts the quality of life of RDEB patients, necessitating frequent use of opioids. In the Phase 3 VIITAL study, EB-101 has been shown to both heal such large chronic wounds and significantly reduce pain. And we continue to see durable clinical benefit of EB-101 with up to 8 years of follow-up in our Phase 1/2a study,” principal investigator Jean Tang, MD, PhD, Professor, Dermatology, Stanford University School of Medicine, said in a statement.4
The VIITAL study evaluated EB-101's effect in 11 participants with RDEB with 43 large chronic wound pairs. These wounds were larger than 20 cm2 of surface area and had remained open for at least 6 months but no more than 21 years (mean, 6.2 years). Wounds randomized to be treated with EB-101 had an 81.4% rate of 50% or greater healing at 6 months while untreated control wounds had a 16.3% rate of 50% healing (P <.0001). The proportion of treated wounds achieving 75% or greater healing and complete healing was also statistically significant compared to control wounds.4
“I think when we are discussing being able to treat this disease effectively, we really need to look at a holistic approach to it... I can see in the near future where a patient is actually using more than one cell and gene therapy,” Brett Kopelan, MA, the executive director of the Dystrophic Epidermolysis Bullosa Research Association (debra) of America, told CGTLive.
Pz-cel may be the second gene therapy approved for RDEB after Krystal Biotech’s beremagene geperpavec (B-VEC, marketed as Vyjuvek) was approved in May 2023.5
