Krystal Sells Priority Review Voucher for $100 Million

Rare Daily Staff

Krystal Biotech said it has sold the Rare Pediatric Disease Priority Review Voucher it received from the U.S. Food and Drug Administration following the approval its dystrophic epidermolysis bullosa therapy Vyjuvek for $100 million.

Under the Rare Pediatric Disease Priority Review Voucher Program, the FDA awards priority review vouchers to sponsors of rare pediatric disease product applications that meet certain criteria. The program is intended to encourage development of new drugs and biologics for the prevention and treatment of rare pediatric diseases. A PRV can be redeemed to receive priority review of a subsequent marketing application for a different product, or alternatively, sold or transferred.

Dystrophic epidermolysis bullosa (DEB) is a rare and serious disease that affects the skin and mucosal tissues caused by one or more mutations in the COL7A1 gene. The COL7A1 gene is responsible for the production of functional COL7 protein that forms anchoring fibrils necessary to bind the dermis or inner layer of the skin to the epidermis or outer layer of the skin. The lack of functional anchoring fibrils in DEB patients leads to extremely fragile skin that blisters and tears with minor friction or trauma. DEB patients suffer from open wounds, which lead to recurrent skin infections and fibrosis that can cause fusion of fingers and toes, and ultimately increase the risk of developing an aggressive form of skin cancer.

Vyjuvek, which uses an engineered herpes simplex virus to deliver a gene that’s much larger than the standard viral vectors, is designed to address the genetic root cause of DEB by delivering functional copies of the human COL7A1 gene to provide wound healing and sustained functional COL7 protein expression with redosing. Vyjuvek is the first-ever redosable gene therapy and the first and only medicine approved by the FDA for the treatment of DEB, both recessive and dominant, that can be administered by a healthcare professional in either a healthcare professional setting or in the home.