FDA Grants Orphan Drug Status to ProQR’s QR-313 as Treatment for Dystrophic EB

The U.S. Food and Drug Administration (FDA) recently granted orphan drug status to ProQR Therapeutics‘ investigational drug QR-313, developed for the treatment of dystrophic epidermolysis bullosa (DEB).

A first-in-class ribonucleic acid (RNA)-based oligonucleotide, QR-313 was designed to address the underlying cause of DEB due to mutations in exon 73 of the COL7A1 gene.

Mutations in exon 73 are known to cause loss of functional collagen type VII (C7) protein. Absence of C7 protein may lead to the loss of anchoring fibrils that normally link the dermal and epidermal layers of the skin together. By a process commonly known as exon skipping – or the exclusion of exon 73 from the mRNA – QR-313 reestablishes the production of functional C7 protein, restoring the functionality of the anchoring fibrils.

An orphan drug is a special FDA designation attributed to investigational therapies being developed for the treatment of rare diseases like DEB. With a therapy that has an orphan drug status, biotech and pharmaceutical companies receive incentives, development program tax benefits, and a waiver of certain application user fees, as well as market exclusivity for up to seven years in the United States.

“We are pleased to have ODD [orphan drug designation] in the U.S. for our QR-313 program targeting dystrophic epidermolysis bullosa,” David M. Rodman, MD, chief development strategy officer at ProQR, said in a press release.

“It highlights the unmet need in this devastating disease, for which we aim to make a meaningful difference. Our goal for this disease is to develop a pipeline of programs that can treat DEB mutations in a targeted manner and to actively advance the pipeline through development,” Rodman added.

ProQR will present posters on QR-313 data at two upcoming scientific conferences: the 5th World Conference of Epidermolysis Bullosa Research Conference (EB2017), Sept. 24-26 in Salzburg, Austria; and the 47th Annual European Society for Dermatological Research (ESDR) Meeting on Sept. 29, also in Salzburg.

The presentations are titled “Local delivery of an antisense oligonucleotide for recessive dystrophic epidermolysis bullosa” and “In vitro evaluation of QR-313; an antisense oligonucleotide designed to skip exon 73 from the COL7A1 mRNA.”

According to ProQR, a first-in-human clinical trial of QR-313 will be initiated in 2018. Clinical data from the program is expected to be available later in 2018.