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, announced today $45 million of Series D equity financing, including a $25-million tranche to fully fund the first Phase 3 clinical study of PRT-201. Proteon's lead product, PRT-201, is a recombinant human elastase in development to prolong the patency and reduce the failure of hemodialysis vascular access in patients with chronic kidney disease (CKD). The Phase 3 study will evaluate PRT-201 in patients undergoing surgical placement of an arteriovenous fistula (AVF), the optimal form of vascular access for hemodialysis patients.

The financing was led by Abingworth LLP, with participation by Deerfield Management Company and Pharmstandard International S.A., a holding company fully committed by OJSC Pharmstandard (LSE: PHST). In addition, the financing included existing investors TVM Capital, Prism VentureWorks, Skyline Ventures, Intersouth Partners, MPM Capital, Devon Park Bioventures, Bessemer Venture Partners, and the Vectis Healthcare and Life Sciences Fund.

'We greatly appreciate the continued support of our existing investors, and we are excited to welcome Abingworth, Deerfield and Pharmstandard as new investors,' said Timothy P. Noyes, President and Chief Executive Officer of Proteon. 'AVF failure causes great suffering for hemodialysis patients, resulting in repeat surgical and endovascular procedures and increased cost of care. We look forward to the initiation of the Phase 3 study later this year, based on results from earlier studies demonstrating that PRT-201 has the potential to provide meaningful benefit to CKD patients.'

Concurrent with the investment, Tim Haines, Partner at Abingworth, and Dmitry Kobyzev, Investment Manager at Inbio Ventures, a management company which represented Pharmstandard in facilitating this investment round, have joined Proteon Therapeutics' Board of Directors.

'We believe PRT-201 has significant potential to improve outcomes in hemodialysis patients undergoing surgical placement of a vascular access and are impressed with the capabilities of the Proteon management to lead this development effort,' said Haines. 'Abingworth is pleased to support Proteon as it advances development of PRT-201 into late-stage clinical evaluation.'

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 result in improved blood flow and prolonged vessel patency. PRT-201 has received fast track and orphan drug designations from the FDA and orphan medicinal product designation from the European Commission for hemodialysis vascular access indications.

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 www.proteontherapeutics.com.

About Abingworth LLP

Abingworth is an international investment group dedicated exclusively to the life sciences and health care sectors. The firm invests across all stages of company development, including early- and late-stage private deals, VIPEs (Venture Investments In Public Equities) Venture growth and public companies. Founded in 1973, Abingworth has a lengthy track record of building market-leading companies. The specialist team of 16 professionals has a broad range of skills, including scientific and business expertise, as well as investment banking, recruitment and legal knowledge. These resources are made available to portfolio companies. Abingworth has funds under management of over $1.25 billion and offices in London, Menlo Park, Calif., and Boston. www.abingworth.com

About Deerfield Management Company

Deerfield is an investment management firm, committed to advancing health care through investment, information and philanthropy. For more information about Deerfield, please visit www.deerfield.com.

About Pharmstandard International S.A./ Inbio Ventures

Pharmstandard International S.A. - a holding company fully committed by OJSC Pharmstandard (LSE:PHST) - is a venture investments fund focused on innovative drugs/therapies with strong potential at global markets and in Russia and Commonwealth of Independent States (CIS) countries. Inbio Ventures is a management company representing Pharmstandard International, S.A., and providing professional support in venture transactions. For more information, please visit www.inbio-ventures.com.