NxStage Medical Announces Needle Supply Agreement with DaVita

LAWRENCE, Mass., Jan. 7 /PRNewswire-FirstCall/ -- NxStage Medical, Inc. , a leading manufacturer of innovative dialysis products, today announced that it has signed a five-year agreement with DaVita, Inc. to continue to supply DaVita's dialysis centers with MasterGuard and ButtonHole safety needle sets, subject to certain terms and conditions. Safety needles are essential products used to access patients' blood during the vast majority of chronic dialysis therapy treatments. MasterGuard is the leading product in this market, and became part of NxStage's product portfolio through the recent acquisition of Medisystems.

DaVita and its predecessors have a long, successful history with Medisystems brand needles.

"We are very pleased to continue our long-standing relationship as DaVita's primary needle supplier," said Jeffrey H. Burbank, President & CEO of NxStage Medical. "Medisystems' high quality, innovative products was one of the key reasons we acquired the company last year. This new agreement with DaVita solidifies NxStage's position as a dialysis industry leader in-center, as well as in the critical care and home hemodialysis markets."

About NxStage Medical

NxStage Medical, Inc. is a medical device company, headquartered in Lawrence, Massachusetts, USA, that develops, manufactures and markets innovative products for the treatment of end-stage renal disease, or ESRD, and acute kidney failure. For more information on NxStage and its products, please visit the Company's website at http://www.nxstage.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 needle and other products and other factors that are discussed in NxStage's filings with the Securities and Exchange Commission, including the Quarterly Report on Form 10-Q for the quarter ended September 30, 2007. 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.

CONTACT: Stephanie Marks of NxStage Medical, Inc., 1-888-698-6472, ir@nxstage.com Web site: http://www.nxstage.com/