Pervasis Therapeutics Receives FDA Clearance for Pivotal Phase 3 Trial of Vascugel®

Pervasis Therapeutics, Inc.

Pervasis Therapeutics Receives FDA Clearance for Pivotal Phase 3 Trial of Vascugel®

February 1, 2010

Agreement Follows Recent Publication of Data for Lead Programs in ESRD, PAD

CAMBRIDGE, Mass., Feb. 1 /PRNewswire/ -- Pervasis Therapeutics, Inc. today announced that it has reached an agreement with the U.S. Food and Drug Administration (FDA) on the design of a pivotal Phase 3 clinical trial for Vascugel®, an investigational new drug for the prevention of hemodialysis access graft failure. The agreement was made under the FDA's Special Protocol Assessment (SPA) procedure. Pervasis expects to initiate the study in 2010.

"We are pleased that the FDA approved the SPA agreement and are confident that we now have a clearly defined path to submission of a Biologics License Application for Vascugel," said Fred Chereau, president and chief executive officer at Pervasis. "We look forward to beginning the Phase 3 study and to confirming the safety and efficacy results from our Phase 1/2 study in a larger patient population."

This Phase 3, single-blind, randomized, controlled, multi-center study will evaluate the efficacy and safety of Vascugel in approximately 390 patients with end-stage renal disease (ESRD) undergoing creation of an arteriovenous (AV) graft for hemodialysis access. The primary objective of this study will be to evaluate the efficacy of Vascugel in extending the duration of primary patency (lack of vessel obstruction) as compared to standard-of-care treatment.

Under the SPA procedure, FDA formalizes its agreement that the design of the Phase 3 trial is acceptable to support a regulatory submission seeking new drug approval.

The SPA agreement follows the recent publication of positive Phase 1/2 results for Vascugel in the December issue of the Journal of Vascular Surgery (Conte et al. J Vasc Surg 2009; 50:1359-68). The study was designed to assess feasibility, safety, and preliminary effects on patency of Vascugel in patients requiring an AV fistula or AV graft for hemodialysis. Results showed that Vascugel was well tolerated, with no difference in early complication rates between the Vascugel and placebo groups at four weeks (10.9 percent vs. 21.1 percent, respectively). Results also demonstrated a trend for improved primary patency at 24 weeks in patients treated with Vascugel compared to placebo.

Building on the successful results to date for Vascugel, Pervasis continues to apply its proprietary endothelial technology platform to develop additional therapies to treat vascular disease. Data for PVS-10200, a preclinical compound being developed to treat interventions performed for peripheral arterial disease (PAD), were published in the December issue of the Journal of Vascular and Interventional Radiology (Nugent et al. J Vasc Interv Radiol 2009; 20(12):1617-1624). In a preclinical model of PAD, administration of PVS-10200 at the time of angioplasty and stent placement enhanced blood vessel healing compared to angioplasty and stenting alone. Pervasis is now preparing to begin a Phase 1/2 study of PVS-10200 in the first half of 2010.

About Pervasis

Pervasis Therapeutics, Inc. is a clinical stage company developing a broad portfolio of biologically active therapeutics. Building on its deep understanding of the specialized role that the endothelium plays in regulating natural healing and repair processes associated with disease, Pervasis is advancing groundbreaking new therapies to dramatically improve the outcomes of common vascular interventions, such as arteriovenous access, angioplasties, stents, and peripheral and coronary bypass grafts -- the failure of which result in serious complications and a significant increase in medical costs. The company's most advanced program, Vascugel®, has demonstrated proof of concept and safety in two Phase 2 trials in patients undergoing arteriovenous access procedures for hemodialysis. Pervasis is also applying its platform technology to develop products in therapeutic areas beyond vascular disease, such as inflammatory and orthopedic diseases.

Pervasis is a privately held company with funding from Flagship Ventures, Polaris Venture Partners, Highland Capital Partners and the Richter Family Fund. For more information, please visit www.pervasistx.com.

About Vascugel and PVS-10200

Vascugel, a novel, biologically active therapy developed using tissue-engineered allogeneic endothelium, is under investigation for enhancing blood vessel repair and promoting vascular health. In May 2009, Vascugel received an Orphan Drug designation from the U.S. Food and Drug Administration for the prevention of arteriovenous fistula or arteriovenous graft failure in patients with end-stage renal disease.

PVS-10200, a biologically active therapy developed using tissue-engineered allogeneic endothelium, is designed to reestablish healthy vasculature following common interventions to treat peripheral arterial disease (PAD) and potentially other conditions. PAD is a systemic disease in which plaque builds up in arteries, causing the restriction of blood flow that can lead to serious complications, including limb amputation, kidney failure, stroke and death.

About End-stage Renal Disease (ESRD)

End-stage renal disease (ESRD) is an advanced and irreversible condition treated mainly by hemodialysis or kidney transplantation. It is estimated more than 350,000 Americans with ESRD receive hemodialysis each year.(1) Complications following AV access procedures for hemodialysis are common, and an estimated 60 percent of AV grafts fail after one year.(2) (3) Vascugel may represent a fundamentally new approach to preventing AV access failure by helping to regulate the body's healing response following the creation of an AV access site.

This news release contains certain forward-looking statements that involve risks and uncertainties. Such statements are only predictions and the company's actual results may differ materially from those anticipated in these forward-looking statements. Factors that may cause such differences include the timing of clinical trials, the risk that products that appeared promising in early research and clinical trials do not demonstrate safety or efficacy in clinical trials and the risk that the company will not obtain approval to market its products.

(1) http://kidney.niddk.nih.gov/kudiseases/pubs/kustats/index.htm. Last accessed January 27, 2010.

(2) Dixon et al. DAC Study Group. Effect of dipyridamole plus aspirin on hemodialysis graft patency. N Engl J Med. 2009; 360: 2191-2201.

(3) Hayashi et al. Vascular access for hemodialysis. Nat Clin Pract Nephrol. 2006; 2: 504-513.

Company Contact:

Margaret O'Toole
Pervasis Therapeutics, Inc.
617-871-1201

Media Contact:

Jaren Irene Madden
Feinstein Kean Healthcare
617-761-6727