NxStage® Reports Significant Interim FREEDOM Study Results
Significant reduction in prescribed anti-hypertensive medications; Lower than expected mortality

LAWRENCE, Mass., Oct. 27 /PRNewswire/ -- NxStage Medical, Inc. (Nasdaq: NXTM), a leading manufacturer of innovative dialysis products, today announced the latest interim results from its ongoing FREEDOM study. The FREEDOM data will be presented in posters at the American Society of Nephrology (ASN) Renal Week 2009, from October 27th to November 1st in San Diego.

The FREEDOM analysis shows a significant reduction in the need for anti-hypertensive medications experienced by patients performing daily home hemodialysis (DHD) therapy with the NxStage System One™, and this reduction was maintained through the twelve month study period. These interim results from the FREEDOM study compared the number of anti-hypertensive medications (used to control blood pressure) that were prescribed at the patients' baseline (when they were on thrice-weekly, in-center hemodialysis), then at 4-months and 12-months after starting DHD. The study also looked at the number of patients who were not prescribed anti-hypertensive medications at those intervals. Key findings include:

-- A nearly 50% reduction in the average number of prescribed anti-hypertensive medications over 12 months;
-- 33% of patients completely discontinued anti-hypertensive medications; and,
-- 56% of patients experienced a 50% or greater decrease in anti-hypertensive medications.

Additional FREEDOM data demonstrates a 40% reduction in expected mortality of patients using daily home hemodialysis (DHD) therapy with the NxStage System One when compared to patients from the United States Renal Data System (USRDS). The Standardized Mortality Ratio (SMR), calculated from actual vs. expected deaths, was 0.6 for DHD patients compared to patients from the USRDS of similar age, gender, race and primary cause of ESRD.

"In an attempt to see if the decreased morality observed in the study would remain after statistical adjustment, this analysis utilized a well-established formula with conservative assumptions to calculate a SMR. Even after correcting for these variables, patients using daily home hemodialysis therapy with the System One experienced a significantly lower rate of death when compared to similar patients from the USRDS database," stated Brent Miller, M.D., an Investigator involved with the study from Washington University in St Louis. "This is further clinical evidence that more frequent home hemodialysis can lead to better clinical outcomes. These results should help energize patients, nephrologists, healthcare providers and public policy makers to continue to invest in and advance this therapy to alleviate the burden of dialysis."

Full abstracts can be read online at www.asn-online.org.

About the FREEDOM Study
The FREEDOM study (Following Rehabilitation, Economics and Everyday-Dialysis Outcome Measurements) is a multicenter prospective cohort study designed to measure the clinical and economic benefits of daily home hemodialysis, as compared to conventional, thrice-weekly in-center hemodialysis. The study will include up to 500 daily home hemodialysis patients at up to 70 clinical sites, and a matched cohort control group of 5,000 patients on conventional treatment chosen at random and derived from the USRDS database. All daily home hemodialysis patients use the NxStage System One™ as their treatment delivery system, and all have Medicare as their primary insurance payer. As part of the study, participants are asked to complete a series of Quality of Life surveys at the time of enrollment (baseline), at 4 and 12 months, and every 6 months thereafter as long as they remain in the study. NxStage Medical, Inc. is sponsoring the FREEDOM study.

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 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: expected growth in home daily hemodialysis and the anticipated impact and results of the FREEDOM study 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, 2009. 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
Kristen K. Sheppard, Esq.
VP, Investor Relations
978-332-5923
ksheppard @nxstage.com