Journal of Cardiovascular Pharmacology Publishes Positive Nonclinical Results of Proteon Therapeutics' PRT-201 in Peripheral Artery Disease

Results Complement Ongoing Phase 1 Clinical Study

Waltham, Massachusetts, UNITED STATES

WALTHAM, Mass., Jan. 8, 2015 (GLOBE NEWSWIRE) -- Proteon Therapeutics Inc. (Nasdaq:PRTO), a company developing novel, first-in-class pharmaceuticals to address the medical needs of patients with kidney and vascular diseases, today announced publication of nonclinical data on PRT-201 (vonapanitase) in peripheral artery disease (PAD). This ex vivo study evaluated the effect of a single treatment of PRT-201, an investigational drug, on atherosclerotic human arteries. The positive results, published in the December issue of the Journal of Cardiovascular Pharmacology, support Proteon's clinical development program in PAD. Proteon's Senior Vice President and Chief Medical Officer, Steven Burke, M.D., is the senior author of the published manuscript. Click here to access the entire article.

"These data published in the Journal of Cardiovascular Pharmacology support our belief that PRT-201 may have multiple surgical and endovascular applications in addition to our lead application in hemodialysis vascular access," said Timothy Noyes, President and Chief Executive Officer of Proteon. "We now look forward to the results of our Phase 1 study evaluating endovascular treatment with PRT-201 for patients suffering from PAD, which we expect in the second half of 2015."

PRT-201 has the potential to treat patients suffering from a number of renal or vascular diseases for which there currently are limited therapeutic options, including PAD. The results published in the Journal of Cardiovascular Pharmacology support Proteon's ongoing Phase 1 clinical study of PRT-201, which enrolled patients with symptomatic PAD of the superficial femoral or popliteal artery. Immediately following angioplasty, patients received PRT-201 delivered to the arterial wall via a catheter-based approach using the Mercator MedSystems Bullfrog® Micro-Infusion Device.

Proteon's lead clinical program is evaluating whether PRT-201 can prolong the patency and reduce the failure of hemodialysis vascular access in patients with chronic kidney disease (CKD). Proteon is currently conducting a Phase 3 multicenter, randomized, double-blind, placebo-controlled 300-patient clinical study of PRT-201 in CKD patients undergoing surgical placement of an arteriovenous fistula (AVF) for hemodialysis vascular access. The Phase 3 study follows the completion of a Phase 2 multicenter, randomized, double-blind, placebo-controlled clinical study in which 151 patients were treated.

About Peripheral Arterial Disease

Peripheral artery disease (PAD) is characterized by atherosclerosis in the arteries of the legs, which leads to poor blood flow. Patients with PAD may experience muscle pain during walking, suffer from ulcers that are slow to heal or, in the most severe cases, require amputation. PAD affects eight million Americans and is a significant cause of both morbidity and mortality (source: American Heart Association).

About PRT-201

PRT-201 (vonapanitase) 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, which may result in improved blood flow and prolonged vessel patency. PRT-201 has received fast track and orphan drug designations from the U.S. Food and Drug Administration (FDA) and orphan medicinal product designation from the European Commission for hemodialysis vascular access indications.

About Proteon Therapeutics

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

Cautionary Note Regarding Forward-Looking Statements

This press release contains statements that are, or may be deemed to be, "forward-looking statements." In some cases these forward-looking statements can be identified by the use of forward-looking terminology, including the terms "believes," "estimates," "anticipates," "expects," "plans," "intends," "may," "could," "might," "will," "should," "approximately," "potential," or, in each case, their negatives or other variations thereon or comparable terminology, although not all forward-looking statements contain these words. These statements, including those regarding the potential surgical and endovascular applications for PRT-201, the timing of results of the Phase 1 study for patients with PAD, the potential treatment of renal and vascular diseases with PRT-201, the effect of PRT-201 in patients with CKD, and those relating to future events or our future financial performance or condition, involve substantial known and unknown risks, uncertainties and other important factors that may cause our actual results, levels of activity, performance or achievements to differ materially from those expressed or implied by these forward-looking statements. These risks, uncertainties and other factors, including whether our cash resources will be sufficient to fund the our operating expenses and capital expenditure requirements for the period anticipated; whether data from early clinical trials will be indicative of the data that will be obtained from future clinical trials; whether PRT-201 will advance through the clinical trial process on the anticipated timeline and warrant submission for regulatory approval; whether such a submission would receive approval from the Food and Drug Administration or equivalent foreign regulatory agencies on a timely basis or at all; and whether we can successfully commercialize and market our product candidates, are described more fully in our Quarterly Report on Form 10-Q for the quarter ended September 30, 2014 as filed with the Securities and Exchange Commission on November 25, 2014, particularly in the sections titled "Risk Factors" and "Management's Discussion and Analysis of Financial Condition and Results of Operations." In light of the significant uncertainties in our forward-looking statements, you should not place undue reliance on these statements or regard these statements as a representation or warranty by us or any other person that we will achieve our objectives and plans in any specified time frame, or at all. The forward-looking statements contained in this press release represent our estimates and assumptions only as of the date of this press release and, except as required by law, we undertake no obligation to update or revise publicly any forward-looking statements, whether as a result of new information, future events or otherwise after the date of this press release.

Company Contact
George Eldridge, Senior Vice President and Chief Financial Officer

Media Contact 
Chris Erdman or Lynnea Olivarez, MacDougall Biomedical Communications