NxStage Medical to Present at the Thomas Weisel Partners Healthcare Conference on September 5, 2007

Wednesday August 29, 2007

LAWRENCE, Mass., Aug. 29 /PRNewswire-FirstCall/ — NxStage Medical, Inc. (Nasdaq: NXTM), the manufacturer of the NxStage System One&#153 portable kidney dialysis machine, today announced that Jeffrey H. Burbank, Chief Executive Officer, will participate in the Thomas Weisel Partners Healthcare Conference. Mr. Burbank is scheduled to present an overview of the Company at 2:05 p.m. Eastern Time on September 5, 2007 at The Four Seasons Hotel in Boston, MA.

To listen to the audio web cast of the presentation during the event, please visit: www.nxstage.com and click on ‘Investor Information’. A replay will be available beginning September 7, 2007 for 30 days.

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 Mr. Burbank’s plans to present at the Thomas Weisel Partners Healthcare Conference. NxStage specifically disclaims any obligation to update these forward-looking statements. These forward-looking statements should not be relied upon as representing NxStage’s expectations or beliefs as of any date subsequent to the date of this press release.

About NxStage Medical:

NxStage Medical, Inc. (Nasdaq: NXTM) 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 www.nxstage.com.

SOURCE NxStage Medical, Inc.

Contact:
Kristen K. Sheppard, Esq.
Vice President, Investor Relations
NxStage Medical Inc. (NXTM)
978/332-5923
Web site: http://www.nxstage.com