NxStage Medical Provides Update on Medisystems A...( U.S. Antitrust Review...)

U.S. Antitrust Review Successfully Completed Michael J. Webb Promoted to Newly Created Role of Senior Vice President of

Quality, Regulatory, and Clinical Affairs Philip R. Licari to Step Down as Chief Operating Officer upon Closing of

Planned Acquisition

LAWRENCE, Mass., Aug. 29 /PRNewswire-FirstCall/ -- NxStage Medical, Inc. (Nasdaq: NXTM), the manufacturer of the NxStage System One (TM) portable kidney dialysis machine, today announced that U.S. antitrust authorities have completed their review of the Company's acquisition of Medisystems Corporation and certain affiliated entities. The Company expects to close the transaction in the fourth quarter of 2007.

In anticipation of the closing, NxStage is starting to implement key organizational changes intended to allow the Company to better resource capabilities that are critical to the growth of the business. Effective immediately, Michael J. Webb has been promoted to the newly created role of Senior Vice President of Quality, Regulatory and Clinical Affairs.

"We are elevating the lead quality assurance position at NxStage because product quality is of the utmost importance to us. Mike Webb has more than 15 years of experience in medical device quality assurance, regulatory affairs, manufacturing, operations, engineering, development, and vendor management," said Jeffrey H. Burbank, President & CEO of NxStage Medical. "Quality is a critical aspect of our growing business and I am confident that Mike will advance NxStage's performance."

Prior to his promotion, Mr. Webb served at the Vice President level in several different roles at NxStage, including disposables manufacturing, opera
'/>"/>