Proteon Therapeutics Announces Orphan Drug Designation in the European Union for PRT-201

WALTHAM, MA. — Proteon Therapeutics, Inc., a privately held biopharmaceutical company developing novel, first-in-class pharmaceuticals to address the critical medical needs of patients with kidney and vascular diseases, today announced that its lead product, PRT-201, has received orphan drug designation in the European Union (EU) for the prevention of arteriovenous access dysfunction in hemodialysis patients. Proteon is investigating the use of PRT-201, a locally acting recombinant human elastase applied during surgical placement of a vascular access, to reduce vascular access failure. PRT‑201 has previously received fast track and orphan drug designations from the U.S. Food and Drug Administration (FDA).

The European Medicines Agency grants orphan designation status to medicines intended to treat, prevent or diagnose diseases that are life-threatening or chronically debilitating in no more than five in 10,000 people in the EU. Based on its orphan status, Proteon is eligible to receive a 10-year market exclusivity period for PRT-201 in the EU, as well as other incentives, including protocol assistance and fee reductions.

“Vascular access is often considered the Achilles’ heel of hemodialysis because of the high rates of failure and poor outcomes following surgical placement of an access,” commented Timothy Noyes, president and chief executive officer of Proteon. “We believe that PRT-201 may provide significant clinical benefit to this orphan population, and we are therefore grateful for this recognition.”

A functioning vascular access is a hemodialysis patient’s lifeline, enabling the patient to undergo chronic hemodialysis. Unfortunately, arteriovenous fistulas (AVFs) and arteriovenous grafts (AVGs), the two forms of permanent vascular access, often experience patency loss, in which the access suffers from a significant reduction in or complete loss of blood flow, precluding hemodialysis. Patients can be subjected to further surgical or interventional procedures to restore blood flow, access abandonment and prolonged exposure to a dialysis catheter, which is associated with increased morbidity and mortality.

A single application of PRT-201 may increase the longevity of AVFs and AVGs by reducing neointimal hyperplasia, the growth of tissues inside blood vessels that results in vessel narrowing and reduced blood flow. Proteon has successfully completed three multicenter, double-blind, placebo-controlled trials in patients undergoing surgical placement of a vascular access. In a 151-patient Phase 2 AVF clinical trial, PRT-201 was well-tolerated and demonstrated improvement in key measures of AVF function. These improvements included an increased percentage of AVFs that developed adequate blood flow for dialysis within 12 weeks of creation (maturation) and a decrease in the percentage of AVFs that developed a thrombosis or required a procedure to restore or maintain patency within one year (loss of primary unassisted patency). Proteon expects to continue clinical development of PRT-201 in 2014.

Proteon is also investigating PRT-201 as a treatment for patients with symptomatic Peripheral Artery Disease (PAD) and is currently enrolling patients in the U.S. in a Phase 1 clinical study.

About PRT-201
PRT-201 is an investigational recombinant human elastase that is being studied for its ability to improve outcomes in patients suffering from vascular disease. Elastase has been shown in preclinical settings to reduce neointimal hyperplasia formation and to cause dilation of segments of arteries and veins. These effects may inhibit stenosis formation and increase vessel diameter, improving blood flow and prolonging vessel patency. Prolonged patency may lead to fewer corrective surgical and interventional procedures, fewer hospitalizations, less suffering for patients and lower health care costs. PRT-201 has received fast track and orphan drug designations from the FDA for hemodialysis vascular access.

About Proteon Therapeutics
Proteon Therapeutics, Inc., is a privately held biopharmaceutical company developing novel, first-in-class pharmaceuticals to address the critical medical needs of patients with kidney and vascular diseases. The company is headquartered in Waltham, Mass. For additional information, please visit

George Eldridge, Senior Vice President and Chief Financial Officer
781-890-0102 x1026

Cory Tromblee, MacDougall Biomedical Communications