NxStage and Kimal Announce First International Distribution of Home Hemo

NxStage and Kimal Announce First International Distribution of NxStage's Home Hemodialysis and Critical Care Systems

NxStage's portable home hemodialysis and critical care systems to be available in the UK and Ireland through distribution agreement with Kimal plc

LAWRENCE, Mass., May 7, 2009 -- NxStage Medical, Inc. (Nasdaq: NXTM), a leading manufacturer of innovative dialysis products, today announced that it signed a five-year exclusive distribution agreement with Kimal plc, a distributor of medical device technology across the UK and International healthcare markets, for the promotion, sale, delivery and service of the NxStage System One and certain of the Company's in-center products in the United Kingdom and the Republic of Ireland. This agreement encompasses all three NxStage markets-home, critical care and in-center-and marks the Company's first international expansion for the System One outside of the US and Canada.

Under the terms of the agreement, the NxStage System One and PureFlow SL dialysate preparation system will be available to dialysis centers and hospitals throughout the UK and Ireland exclusively through Kimal. Kimal also has the option to make Medisystems bloodlines and ButtonHole needles available to their customers in these regions.

The UK's National Health Services (NHS) has set the goal of increasing the percentage of UK patients who utilize home hemodialysis to 10 to 15% from its present level of under 2%. The NHS objective was set after a comprehensive study published in 2002 by the National Institute for Clinical Excellence (NICE) suggested that future technology could aid in gaining wider acceptance of home hemodialysis. There are more than 20,000 patients currently receiving dialysis treatment in the UK and Ireland.

"After nearly two million treatments and compelling patient and clinical experience with the NxStage System One in the United States, we are excited to partner with Kimal plc, a long-standing and well-respected leader in medical products distribution," stated Jeff Burbank, CEO of NxStage Medical, Inc. "As an industry pioneer, this agreement represents a significant milestone for our Company, demonstrating the strength of our product offering. We expect that this relationship will provide additional growth opportunities for both companies in 2010 and further our founding mission to provide more patients access to our life-changing therapy." NxStage management expects the agreement to be cash flow neutral to slightly positive upon the joint launch of the distribution relationship in the second half of 2009. NxStage management further stated that they expect initial market penetration to be reflected in revenue contribution in 2010. "We strive to provide our customers with innovative technology that improves patient care," said Alan Press, CEO of Kimal plc. "Through this partnership, dialysis patients will gain immediate access to NxStage's System One that offers treatment flexibility and ease of use to caregivers in critical care settings. NxStage's System One will also provide us the ability to offer a proven, effective home hemodialysis solution to patients receiving dialysis treatment in the UK and Ireland."

NxStage management will discuss its agreement with Kimal plc during its first quarter 2009 financial results conference call on Friday, May 8, 2009 at 9:00 a.m. Eastern Time. To listen to the conference call, please dial 888-396-2369 (domestic) or 617-847-8710 (international). The passcode is 84522793. The call will also be webcast LIVE and can be accessed via the investor relations section of NxStage's website at www.nxstage.com/ir.cfm.

A replay of the conference call will be available 3 hours after the start of the call through May 22, 2009. To access the replay dial 888-286-8010 (domestic) or 617-801-6888 (international) and enter passcode 17843987. An online archive of the conference call can be accessed via the investor relations section of NxStage's website at www.nxstage.com/ir.cfm.

About Kimal plc

Kimal develops, manufactures, markets and distributes innovative medical device technology across the UK and International healthcare market. Kimal's extensive range comprises products for diagnostic and interventional cardiology, radiology, renal disease and oncology. Kimal is a premier provider of customised procedural solutions, being market leader in over 12 countries.

Kimal's strategic vision allows us to develop our core existing business while opening up new opportunities across the world, whether via distributor or principal relationships, direct sales or by joint venture with other like minded organizations.

The company was formed in 1964 as a wholly British owned organisation, a statement which remains true today in the 21st Century. More detail on Kimal can be found by visiting their website - www.kimal.com.

About NxStage Medical
NxStage Medical, Inc. (Nasdaq: NXTM) 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 (ESRD) and acute kidney failure. For more information on NxStage and its products, please visit NxStage's website at www.nxstage.com. To request more information on how to access NxStage products through Kimal, please visit www.nxstage.com/partners/request_information.cfm

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 Kimal's ability to successfully promote, sell and service our products, customer demand for our products in the UK and Ireland, the anticipated impact of the Kimal transaction on cash flow and , revenues, and factors that are discussed in NxStage's filings with the Securities and Exchange Commission, including the Annual Report on Form 10-K for the year ended December 31, 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.

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NxStage Medical:
Kristen K. Sheppard, Esq.
VP, Investor Relations
ksheppard@nxstage.com

Kimal plc
Ken Findlay
Ken_Findlay@kimal.co.uk
+44 7977 250427

http://www.nxstage.com/our_company/partners/kimal.cfm