NxStage(R) to Initiate Manufacturing in Mexico

Wednesday March 21, 2007

LAWRENCE, Mass., March 21 /PRNewswire-FirstCall/ — NxStage Medical, Inc. (Nasdaq: NXTM), the manufacturer of the NxStage System One&#153 portable kidney dialysis machine, announced today that it will initiate manufacturing of certain of its System One products in Fresnillo, Mexico, as part of its ongoing efforts to reduce product costs and optimize operations. Beginning in May, NxStage will execute a phased relocation of the manufacture of its PureFlow SL disposables and System One cycler to a new facility provided by The Entrada Group in Fresnillo. In the future, NxStage also plans to use the facility to manufacture other System One components, including PureFlow SL hardware.

This strategic initiative will enable NxStage to control costs and quality as we expand our manufacturing operations to support our growth and successful PureFlow SL roll-out. After a comprehensive evaluation of alternatives to increase our manufacturing capacity, we concluded that Entrada’s facilities in Mexico, with access to a highly-skilled, low cost workforce, will be a strategic advantage, said Jeff Burbank, President and Chief Executive Officer, NxStage Medical.

The Entrada Group is a Texas-based provider of manufacturing facilities and contract services for companies seeking production capacity in Mexico. The new facility being constructed by Entrada will be designed to meet the U.S. Food and Drug Administration’s (FDA) Quality System Regulations.

The NxStage System One is the first truly portable hemodialysis system cleared for home use by the FDA. Unlike traditional dialysis equipment, the System One plugs into standard electrical outlets, requires no special infrastructure to operate and is easy to use by trained patients and their trained partners. Rather than commuting to and from a dialysis clinic three times per week for scheduled treatment sessions lasting three to four hours, patients who use the NxStage System One have the personal freedom to conduct prescribed treatments at home on their own schedule and to bring the System with them when they travel.

About NxStage Medical

NxStage Medical, Inc. (Nasdaq: NXTM – News) is a medical device company, headquartered in Lawrence, Massachusetts, USA, that develops, manufactures and markets innovative dialysis systems 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. Examples of these forward-looking statements include statements as to the anticipated relocation of manufacturing to Fresnillo, Mexico, anticipated optimization of operations and quality, anticipated reductions in cost, and anticipated increased demand for the System One. All forward- looking statements involve risks, uncertainties and contingencies, many of which are beyond NxStage’s control, which may cause actual results, performance, or achievements to differ materially from anticipated results, performance or achievements, including the timing of construction of the new facility in Fresnillo and certain other factors that may affect future operating results and which are detailed in NxStage’s filings with the Securities and Exchange Commission, including its Annual Report on Form 10-K for the year ended December 31, 2006. 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.

SOURCE NxStage Medical, Inc.

CONTACT:
Fern Lazar
or
Stephanie Marks
NxStage Investor Relations
1-888-698-6472
Web site: http://www.nxstage.com