The NxStage System One is indicated for the treatment of acute and chronic renal failure or fluid overload using hemofiltration, hemodialysis, and/or ultrafiltration, in an acute or chronic care facility. The System is also indicated for hemodialysis with or without ultrafiltration in the home.

All treatments must be administered under physician's prescription, and must be observed by a trained and qualified person, considered to be competent in the use of this device by the prescribing physician.

Device Description

The NxStage System One consists of the NxStage Cycler and the NxStage Cartridge Extracorporeal Blood and Fluid Circuit with or without a pre-attached high permeability filter. The NxStage Cycler is an electro-mechanical device that interfaces with the NxStage Cartridge. The NxStage Cartridge is a single-use extracorporeal blood circuit and fluid management device that mounts integrally within the NxStage Cycler. The System is designed to deliver hemofiltration, hemodialysis and/or ultrafiltration in an acute or chronic care facility and is also indicated for hemodialysis and/or ultrafiltration in the home.

AI/ML Overview

The provided text is a 510(k) Premarket Notification for the NxStage System One, a hemodialysis system. The submission is primarily to expand the indication for use to include hemodialysis in the home. It is not an AI-powered device, but rather a medical device designed for hemofiltration, hemodialysis, and/or ultrafiltration. Therefore, many of the typical AI/ML-specific questions regarding acceptance criteria and study design are not applicable.

Here's an analysis based on the information provided, addressing the applicable points:

1. A table of acceptance criteria and the reported device performance

The document does not explicitly state quantitative acceptance criteria in a table format. Instead, it refers to "parameters used to establish the substantial equivalence" which are:

Ability to deliver the clinically prescribed amount of therapy.
Incidence of adverse events.

The reported device performance in relation to these parameters is that the clinical study demonstrated the device's substantial equivalence to the predicate device in terms of "efficacy, accuracy, and safety" for the expanded home use indication.

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

Sample Size (Test Set): Thirty-two subjects (ITT population).
Data Provenance: The document does not specify the country of origin of the data. It states the study was conducted at "six investigational sites," which are implied to be within the scope of the FDA submission, likely in the US, but not explicitly stated. The study was a prospective clinical study.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)

This is not applicable as the device is a hemodialysis system, not an AI/ML diagnostic tool that relies on expert interpretation for ground truth establishment. The "ground truth" in this context would be the actual clinical outcomes and the ability of the device to perform its intended physiological function, which are measured directly.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

This is not applicable. Adjudication methods like 2+1 or 3+1 are typically used for establishing ground truth in image interpretation or similar diagnostic tasks where human expert consensus is required. For a medical device like a hemodialysis system, the performance is assessed through direct measurement of therapy delivery and observation of adverse events, not through expert adjudication of diagnostic findings.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

This is not applicable. The NxStage System One is a medical device, not an AI system. Therefore, there is no concept of comparing human readers with and without AI assistance for this device.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

This is not applicable. The NxStage System One is a device that requires human interaction (prescription, observation by a trained person) and is not an autonomous algorithm.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

The "ground truth" in this study, implicitly, would be:

Outcomes data: The ability of the device to deliver the "clinically prescribed amount of therapy." This refers to the physiological effect and measurement of dialysis parameters.
Adverse events: The actual occurrence or non-occurrence of adverse events, observed and recorded during the study.

The study design used a "each patient serving as his or her own control" methodology, comparing home environment use to in-center environment use.

8. The sample size for the training set

This is not applicable. The NxStage System One is not an AI/ML device, and thus does not have a "training set" in the context of machine learning. The clinical study described is for validation to expand indications, not for training a model.

9. How the ground truth for the training set was established

This is not applicable for the same reasons as point 8.

Summary

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NxStage Medical, Inc. NxStage System One 510(k) Premarket Notification

K050525
Page 1 of 2

Section IX: 510(k) Summary of Safety & Effectiveness

This 510(k) Summary of Safety and Effectiveness is being submitted in accordance with the requirements of SMDA 1990.

JUN 2 4 2005

A. Submitter's Information:

Name:	NxStage Medical, Inc.
Address:	439 South Union Street, Suite 501Lawrence, MA 01843
Phone:	(978) 687-4700
Fax:	(978) 687-4800
Contact Person:	Norma LeMayManager, Regulatory Affairs
Date of Preparation:	May 26, 2005
B. Device Name:

Trade Name:	NxStage System One
Common/Usual Name:	Hemodialysis System
Classification Name:	High Permeability Hemodialysis System 21 CFR875.5860, (Product Code 78 KDI)

C. Substantial Equivalence/Predicate Devices:

The NxStage System One is substantially equivalent to the following legally marketed predicate device previously cleared by FDA:

NxStage System One, K041424 (cleared on 07/02/04) .

D. Device Description/Indications for Use:

The NxStage System One consists of the NxStage Cycler and the NxStage Cartridge Extracorporeal Blood and Fluid Circuit with or without a pre-attached high The NxStage Cycler is an electro-mechanical device that permeability filter.

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NxStage Medical, Inc. NxStage System One 510/k) Premarket Notification

K050525
Page 2 of 2

Section IX: 510(k) Summary of Safety & Effectiveness

interfaces with the NxStage Cartridge. The NxStage Cartridge is a single-use extracorporeal blood circuit and fluid management device that mounts integrally within the NxStage Cycler. The System is designed to deliver hemofiltration, hemodialysis and/or ultrafiltration in an acute or chronic care facility and is also indicated for hemodialysis and/or ultrafiltration in the home.

Indications for use:

E. Technological Characteristics:

There are no changes in the technological characteristics of the NxStage System One as a result of this 510(k) submission. This submission is to expand the indication for use to include hemodialysis in the home.

F. Summary of Clinical Data obtained:

The clinical study consisted of thirty two subjects (ITT population) at six investigational sites. Parameters used to establish the substantial equivalence of the NxStage System One in a home environment were the ability to deliver the clinically prescribed amount of therapy and the incidence of adverse events. The same treatment regimen performed in an in-center environment served as a basis for comparison, with each patient serving as his or her own control.

NxStage believes that the information and clinical data provided in this 510(k) submission demonstrates that the device is adequately designed for the expansion in the indication for use to include hemodialysis in the home, and is substantially equivalent to the predicate device in terms of efficacy, accuracy, and safety.

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Image /page/2/Picture/1 description: The image shows a logo with a stylized bird design. The bird is depicted with three curved lines representing its body and wings. To the left of the bird, there is a partial circular border with text along the edge. The text is not fully visible, but it appears to be part of the organization's name.

Food and Drug Administration 9200 Corporate Boulevard Rockville MI) 20850

JUN 2 4 2005

Ms. Norma J. LeMay Manager, Regulatory Affairs NxStage Medical, Inc. 439 South Union Street 5th Floor LAWRENCE MA 01843

Re: K050525

Trade/Device Name: NxStage System One Regulation Number: 21 CFR §876.5860 Regulation Name: High permeability hemodialysis system Regulatory Class: II Product Code: KDI Dated: May 26, 2005 Received: May 27, 2005

Dear Ms. LeMay:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced We have reviewed your beatler by the process in the indications for use indications for use stated in above and nave decommission predicate devices marketed in interstate commerce prior to the cholosate) to regard mantine of the Medical Device Amendments, or to devices that have been May 20, 1770, accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a prematice approval application (PMA). You may, therefore, market the do not require approval of a premation provisions of the Act. The general controls provisions of the Act device, subjoc to the general volusion, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (Premarket If your device is classinod (300 above) mison controls. Existing major regulations affecting your Apployal), it they of subject to securaterial Regulations, Title 21, Parts 800 to 898. In addition, FDA uevice can be found ninouncements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FICASE be advised that I DT 3 issuation of aevice complies with other requirements of the Act or any FDA has mass and regulations administered by other Federal agencies. You must comply with all the It carates and rogulations and limited to registration and listing (21 CFR Part 807); labeling ACL S requirements, modulity, but not a more and as set forth in the quality systems (QS) (ZT CFR Part 801); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

{3}------------------------------------------------

This letter will allow you to begin marketing your device as described in your Section 510(k)
The same of the support of any of a location and seguine of your device to a leg This letter will allow you to begin marketing your active of your device of your device to a legally premarket notification. The FDA Inding of Substantial equive and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please If you desire specific advice for your device on our laceming regarited (
contact the Office of Compliance at one of the following numbers, based on the regulation number at the top of this letter:

21 CFR 876.xxxx21 CFR 884.xxxx21 CFR 892.xxxxOther	(Gastroenterology/Renal/Urology)(Obstetrics/Gynecology)(Radiology)	240-276-0115240-276-0115240-276-0120240-276-0100
----------------------------------------------------------------	----------------------------------------------------------------------------	--------------------------------------------------------------

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Also, please note the regulation entitled, finisormation on your responsibilities under the Act from the 807.97). You may obtain other general mionnation on Jour Copyright
Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address 050-2011 01 da gov/cdrh/industry/support/index.html.

Sincerely yours,

Nancy C. Brogdon

Nancy C. Brogdon Director, Division of Reproductive, Abdominal, and Radiological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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INDICATIONS FOR USE

K050525

NxStage System One

510(k) Number (if known):

Device Name:

Indications for Use:

Prescription Use _____________________________________________________________________________________________________________________________________________________________ X (Part 21 CFR 801 Subpart D) AND/OR

Over-The-Counter Use_ (21 CFR 807 Subpart C)

(Please do not write Below this line-continue on another page if needed)

Concurrence of CDRH, Office of Device Evaluation (ODE)

David h. Seymore

(Division Sign-Off) Division of Reproductive, Ahdominal and Radiological Dev 510(k) Number

Page 1 of 1

Regulation Number and Section

§ 876.5860 High permeability hemodialysis system.

(a)
Identification. A high permeability hemodialysis system is a device intended for use as an artificial kidney system for the treatment of patients with renal failure, fluid overload, or toxemic conditions by performing such therapies as hemodialysis, hemofiltration, hemoconcentration, and hemodiafiltration. Using a hemodialyzer with a semipermeable membrane that is more permeable to water than the semipermeable membrane of the conventional hemodialysis system (§ 876.5820), the high permeability hemodialysis system removes toxins or excess fluid from the patient's blood using the principles of convection (via a high ultrafiltration rate) and/or diffusion (via a concentration gradient in dialysate). During treatment, blood is circulated from the patient through the hemodialyzer's blood compartment, while the dialysate solution flows countercurrent through the dialysate compartment. In this process, toxins and/or fluid are transferred across the membrane from the blood to the dialysate compartment. The hemodialysis delivery machine controls and monitors the parameters related to this processing, including the rate at which blood and dialysate are pumped through the system, and the rate at which fluid is removed from the patient. The high permeability hemodialysis system consists of the following devices:(1) The hemodialyzer consists of a semipermeable membrane with an in vitro ultrafiltration coefficient (K
uf ) greater than 8 milliliters per hour per conventional millimeter of mercury, as measured with bovine or expired human blood, and is used with either an automated ultrafiltration controller or anther method of ultrafiltration control to prevent fluid imbalance.(2) The hemodialysis delivery machine is similar to the extracorporeal blood system and dialysate delivery system of the hemodialysis system and accessories (§ 876.5820), with the addition of an ultrafiltration controller and mechanisms that monitor and/or control such parameters as fluid balance, dialysate composition, and patient treatment parameters (e.g., blood pressure, hematocrit, urea, etc.).
(3) The high permeability hemodialysis system accessories include, but are not limited to, tubing lines and various treatment related monitors (e.g., dialysate pH, blood pressure, hematocrit, and blood recirculation monitors).
(b)
Classification. Class II. The special controls for this device are FDA's:(1) “Use of International Standard ISO 10993 ‘Biological Evaluation of Medical Device—Part I: Evaluation and Testing,’ ”
(2) “Guidance for the Content of 510(k)s for Conventional and High Permeability Hemodialyzers,”
(3) “Guidance for Industry and CDRH Reviewers on the Content of Premarket Notifications for Hemodialysis Delivery Systems,”
(4) “Guidance for the Content of Premarket Notifications for Water Purification Components and Systems for Hemodialysis,” and
(5) “Guidance for Hemodialyzer Reuse Labeling.”