NxStage Medical, Inc. Announces Blood Tubing Set Agreement with DaVita Inc.

LAWRENCE, Mass., Sept. 4 /PRNewswire/ -- NxStage Medical, Inc. , a leading manufacturer of innovative dialysis products, today announced that it has signed a one-year extension of its existing agreement with DaVita Inc. to supply blood tubing sets to DaVita centers.

"We are very pleased to affirm our long-standing relationship as DaVita's preferred bloodline vendor," said Jeffrey H. Burbank, President and Chief Executive Officer of NxStage Medical. "This contract demonstrates both the strength of our in-center Medisystems product offering and our ability to set the standard for value in the market. With this supply agreement now in place, we are turning our focus to executing against plans to gain further manufacturing efficiencies."

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 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 blood tubing sets 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 June 30, 2008. 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: Kristen K. Sheppard, Esq., VP, Investor Relations of NxStage
Medical, Inc., ksheppard@nxstage.com

Web site: http://www.nxstage.com/