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Today, the US Food and Drug Administration (FDA) approved prademagene zamikeracel cellular sheets (pz-cel, Zevaskyn), the first autologous cell-based gene therapy for treating wounds in adults and children with recessive dystrophic epidermolysis bullosa (RDEB), a rare, debilitating genetic skin disease.

RDEB has no cure, and patients often have large open wounds with a high risk of systemic infection. Pz-cel, with gene-modified sheets made using human and animal material, is the only FDA-approved product to treat RDEB wounds with a single application, the manufacturer, Abeona Therapeutics, said in its press release announcing approval. 

The list price for the one-time treatment will be $3.1 million, according to the company. 

Approval was based on the multicenter, randomized, intrapatient-controlled phase 3 VIITAL study of patients ages 6 years and older with RDEB, which showed pz-cel resulted in significant wound healing and reduced pain after one treatment. 

The pivotal trial met its two coprimary endpoints demonstrating statistically significant healing of 50% or more from baseline in large chronic RDEB wounds and pain reduction from baseline based on the Wong-Baker FACES scale, evaluated 6 months after treatment.

Of the 43 large, chronic wounds treated with one pz-cel application, 81% of wounds showed 50% or more healing (P < .0001) at 6 months, compared with 16% of the 43 matched control wounds treated with standard of care. The most common adverse events, which included procedural pain and itch, were observed in fewer than 5% of patients. No serious adverse events have been observed, the company stated. 

“After many years of work, it is great to see this FDA approval of Zevaskyn. The EB patients deserve all that we can do for them,” M. Peter Marinkovich, MD, associate professor of dermatology at Stanford University, Stanford, California, and co-principal investigator of the VIITAL study, said in the press release.

The cause of RDEB is a defect in the COL7A1 gene that results in an individual’s inability to produce type VII collagen. People with RDEB have extremely fragile skin with extensive blistering and severe wounds that often cover more than 30% of their body, and in some cases up to 80%, according to the company. The wounds cause debilitating pain and systemic complications that affect length and quality of life. 

According to the company release, pz-cell “incorporates the functional type VII collagen-producing COL7A1 gene into a patient’s own skin cells, ex vivo, using a replication-incompetent retroviral vector to produce functional type VII collagen in treated wounds.” 

“This therapeutic option will nicely complement recently approved topical products,” Amy Paller, MD, professor of dermatology and pediatrics, Northwestern University, Chicago, said in the company release. “Grafting gene-corrected skin onto chronically open wounds of patients with recessive dystrophic epidermolysis bullosa promises the potential to provide long-term healing of wounds, reduction in pain and reduced risk of infection.” 

A phase 1/2 study showed the treatment’s potential long-term benefit, according to the company. The single center, open-label study in 38 chronic wounds in seven patients showed that one surgical application of pz-cel resulted in long-term improvement at treated sites over a median follow-up of 6.9 years (range, 4-8 years).

The manufacturer says pz-cel is expected to be available through Qualified Treatment Centers — recognized EB centers in the United States with experience in cell and gene therapy — in the third quarter of 2025.

The company notes that serious allergic reactions to pz-cel can occur and patients should seek immediate medical help if they experience symptoms including itching, swelling, hives, difficulty breathing, runny nose, watery eyes, or nausea. Anaphylaxis is possible in rare cases.

The company also states there is a potential risk that pz-cel treatment may contribute to the development of cancer “because of how the therapy works,” and that “patients should be monitored for the rest of their lives to check for any signs of cancer.”

Abeona’s patient support program offers help in understanding insurance benefits and financial assistance options. 

This approval comes almost 2 years after the FDA approved the first-ever topical gene therapy for EB, beremagene geperpavec (Vyjuvek), for treating wounds in patients 6 months of age and older with recessive or dominant dystrophic EB.