NxStage(R) Expands Streamline(R) Blood Tubing Set and MasterGuard(R) Needle Supply Agreement with Renal Advantage Inc.

Monday April 12, 2010

LAWRENCE, Mass. and NASHVILLE, Tenn., April 12, 2010 /PRNewswire via COMTEX/ –NxStage Medical, Inc. (Nasdaq: NXTM), a leading manufacturer of innovative dialysis products, today announced that its Medisystems division has expanded the scope of its existing long-term product supply agreement with Renal Advantage Inc. (RAI), the third largest for profit provider of dialysis services in the U.S. Pursuant to the terms of the amendment, the original agreement has been expanded to include 43 additional facilities acquired from National Renal Alliance. As a result, NxStage will supply the Streamline&reg airless blood tubing set, as well as MasterGuard&reg needles and other products, to these additional facilities in RAI’s dialysis center network.

RAI has been a strong long-term customer of our Medisystems division, as well as a strategic partner with NxStage within the Home hemodialysis market. We are extremely pleased that RAI is broadening its commitment to our products by integrating Streamline and MasterGuard into all of their in-center operations, said Jeffrey H. Burbank, president and chief executive officer of NxStage Medical. We believe that our innovative technology and high quality product portfolio remain significant drivers for end user demand.

We are delighted to expand our relationship with NxStage to extend the benefits of Streamline and MasterGuard to our patients, said Dean Weiland, chief operations officer of RAI. We originally implemented Streamline into 45 of our facilities. After reviewing the clinical and operational data we collected from those centers, we determined that the KT/V improvement, operational cost savings and staff satisfaction were significant and validated the standardization of Streamline across all of facilities we acquired from National Renal Alliance. We believe that Streamline helps to position our facilities for clinical and operational excellence as we prepare for ‘bundled’ reimbursement.

RAI’s Rialto facility will be showcasing a poster summary of its clinical and operational progress with Streamline at the National Kidney Foundation Spring Clinical Meeting in Orlando, Florida on April 14, 2010.

Medisystems’ latest generation blood tubing set is the Streamline&reg, which features an efficient and airless design intended to improve clinical and economic performance. Streamline is designed to reduce dialysate flow, dialyzer size, treatment time, minimize heparin and waste, and optimize dose delivery, as measured in Kt/V. Streamline also includes Medisystems’ patented LockSite&reg needleless access ports, which eliminate the need for sharp needles or costlier guarded needles to be used with the tubing set during dialysis. MasterGuard&reg needle protectors are proven in published clinical studies to reduce needlestick injuries while not affecting or interfering with site selection, cannulation technique or tape down. MasterGuard AVF needles are designed to achieve the smoothest possible flow path to reduce clotting, lower pressure drops and reduce turbulence stress on the patient’s blood.

About NxStage Medical

NxStage Medical, Inc. (Nasdaq: NXTM) is a medical device company, headquartered in Lawrence, Massachusetts, USA, that develops, manufactures and markets innovative products for the treatment of ESRD and acute kidney failure. For more information on NxStage and its products, please visit the company’s website at http://www.nxstage.com.

About Renal Advantage Inc.

Based in Brentwood, Tennessee, RA Group Holdings, Inc., through its wholly owned entity, Renal Advantage Inc., provides dialysis services to patients with chronic kidney failure, also known as end-stage renal disease (ESRD). With the completion of the acquisition of National Renal Alliance, RA Group Holdings, through its operating companies, provides services to approximately 12,000 patients in 149 dialysis centers in 19 states. RAI also delivers laboratory services through RenaLab, a state-of-the-art independent clinical laboratory located in Jackson, Miss. Founded by veteran healthcare executives, RAI’s growth plan began with its acquisition of 73 dialysis centers in October 2005, which was financed in partnership with Welsh, Carson, Anderson & Stowe. For more information, visit RAI’s website at www.renaladvantage.com.

Forward-Looking Statements

This release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements contained in this release that are not clearly historical in nature are forward-looking, and the words anticipate, believe, expect, estimate, plan, and similar expressions are generally intended to identify forward-looking statements. Actual results may differ materially from those indicated by these forward-looking statements as a result of various important factors including, but not limited to, changes relating to customer demand for NxStage’s blood tubing sets and other products and other factors that are discussed in NxStage’s filings with the Securities and Exchange Commission, including the Annual Report on Form 10-K for the year ended December 31, 2009. NxStage is under no obligation to (and expressly disclaims any such obligation to) update or alter its forward-looking statements, whether as a result of new information, future events or otherwise.

 Contacts: Kristen K. Sheppard, Esq. Todd Smith VP, Investor Relations Deane Smith Media Innovations ksheppard@nxstage.com todd.smith@deanesmithmedia.com 

SOURCE NxStage Medical, Inc.