The NxStage PureFlow-B Solutions (with bicarbonate buffer) are non-pyrogenic dialysis solutions provided in single use flexible bags. The PureFlow-B Solutions are intended for use with renal replacement therapy systems that utilize sterile premixed dialysate. The range of constituents allows the physician to prescribe different electrolyte compositions that meet the specific needs of individual patients.

AI/ML Overview

Acceptance Criteria and Study for NxStage PureFlow-B Solution

This document details the acceptance criteria and the study that "proves" the NxStage PureFlow-B Solution device meets those criteria, based on the provided 510(k) summary.

Note: The provided document is a 510(k) summary for a premarket notification, which focuses on demonstrating substantial equivalence to a previously cleared device. It does not contain an "acceptance criteria" table in the traditional sense of a clinical trial or performance study with numerical targets and measured performance. Instead, the "acceptance criteria" for a 510(k) are met by demonstrating the modified device is as safe and effective as a predicate device.

Therefore, the interpretation of "acceptance criteria" here refers to the requirements for demonstrating substantial equivalence, and "reported device performance" refers to the manufacturer's assertion of meeting those requirements through comparison to the predicate.

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria (for Substantial Equivalence)	Reported Device Performance
I. Device Modification Documentation: Compliance with 21 CFR 820.30 Design Control requirements (as per FDA's guidance document for Special 510(k)s).	NxStage has provided certification of compliance to 21 CFR 820.30 Design Control requirements. This implies the modification process followed established quality system procedures and documented controls were in place to ensure the safety and effectiveness of the changes.
II. Design Validation: Validation of the modified device to confirm it meets design specifications.	The submission states that the modified device "meets Design validations." This indicates that the manufacturer performed testing and verification to ensure the modified device performs as intended and meets its design requirements. The specific validation methods are not detailed in this summary.
III. Substantial Equivalence to Predicate Device (K042045): The modified device is as safe and effective as the predicate device.	The modified NxStage PureFlow-B Solution has been compared to the baseline (predicate device, K042045) and found to be "substantially equivalent." This is the core conclusion of the 510(k) submission, indicating that any changes made do not raise new questions of safety or effectiveness and that the device performs similarly to one already legally marketed.
IV. Meets Minimum Requirements: The device fulfills all applicable regulatory and safety requirements.	"The modified NxStage PureFlow-B Solution has been shown to meet the minimum requirements that are considered applicable." This general statement covers compliance with relevant standards, regulations, and generally accepted principles for medical devices of this type. The specific "minimum requirements" are not itemized but would include aspects like sterility, biocompatibility, chemical composition, etc.

Study Information & Details:

Regarding a "study" that proves the device meets (aforementioned) acceptance criteria:

The provided 510(k) summary describes a Special 510(k) Device Modification. For this type of submission, the "study" is primarily a demonstration of adherence to design control principles and a comparison to a predicate device, rather than a traditional clinical study with patient outcomes or a statistical analysis of a "test set."

Sample size used for the test set and the data provenance:
- Sample Size: Not applicable in the context of a traditional performance "test set" with patient data or a specific number of instances. The "test set" here refers to the comparisons and validations performed during the design control process. No specific sample sizes for laboratory tests, stability tests, or other verification activities are mentioned in this summary.
- Data Provenance: Not explicitly stated as "country of origin" for data, but the submission is from NxStage Medical, Inc. based in Lawrence, MA, USA, and is submitted to the US FDA. The "study" here is a regulatory affirmation based on design controls.
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not applicable in the context of expert review of images or clinical cases for ground truth. This is a technical and regulatory comparison, not a diagnostic device evaluation. The "experts" involved would be the engineers, quality assurance personnel, and regulatory affairs specialists at NxStage Medical, Inc., who are responsible for ensuring compliance and technical validity.
Adjudication method (e.g., 2+1, 3+1, none) for the test set:
- Not applicable. Adjudication methods are typically used in clinical studies or reader studies where expert consensus is needed for ambiguous or subjective evaluations, common in diagnostic imaging. This 510(k) is for a manufacturing modification to a dialysate solution.
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:
- Not applicable. This device is a premixed dialysate for hemodialysis, not an AI-powered diagnostic device or an imaging product. MRMC studies are specific to evaluating diagnostic accuracy, often in imaging.
If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Not applicable. This device is a chemical solution, not a software algorithm.
The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- The "ground truth" for this Special 510(k) is the predicate device (K042045). The modified device's performance, safety profile, and efficacy are compared against the known characteristics and performance of the predicate. The "truth" is that the modified device should meet the same specifications and perform comparably to the predicate. The basis for this "truth" would come from physicochemical testing, stability testing, and potentially limited biocompatibility testing if new materials were involved (though not explicitly detailed in the summary).
The sample size for the training set:
- Not applicable. This is not a machine learning or AI device that requires a "training set."
How the ground truth for the training set was established:
- Not applicable. As above, there is no "training set" for this type of medical device submission.

Summary

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K053286

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DEC 2 2 2005

Section 7

510(K) Summary of Safety Effectiveness

This 510(k) summary of safety and effectiveness information is being summitted in The UTG(K) Bammary of the Safe Medical Device Act (SMDA) of 1990. The accordance with the requirements have been provided in conformance with 21 CFR $807.92.

Date:	November 23, 2005
Common/Usual Name:	Premixed Dialysate for Hemodialysis
Trade/Proprietary Name:	NxStage PureFlow-B Solution
Classification Name:	Hemodialysis systems and accessories(21 CFR 876.5820)
Device Classification:	Class II
Product Code:	78 KPO - Dialysate Concentrate for Hemodialysis(Liquid or Powder)
Device Panel:	Gastroenterology-Urology (GU)/Gastro-Renal(GRDB)
510(k) Sponsor &Owner/Operator:	NxStage Medical, Inc439 South Union St, Suite 501Lawrence, MA 01843Owner/Operator No. 9045797Establishment Registration #3003464075
Contact Person:	Norma LeMayManager, Regulatory Affairs

Device Description:

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K053286 Poper 2012

Substantial Equivalence:

Substantial Equivalence:
This submission is a Special 510(k) Device Modification as described in FDA's guidance This Submison is a creatigm - Alternate Approaches to Demonstrating document entilliou "The Free Market Notifications." In support of this 510(k), NxStage Substantial Equivalierson of compliance to 21 CFR 820.30 Design Control requirements. nas provided cortined. For the more that the modified device that the modified device meets Design validations. The modified NxStage PureFlow-B Solution has been compared to the baseline as cleared in K042045 and found to be substantially equivalent.

Conclusion:

Oonoloon: characteristics, and design control certification, the modified NxStage PureFlow-B Solution has been shown to meet the minimum requirements that are considered Obliation The been of one and found to be substantially equivalent to the baseline device.

Confidential

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Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

DEC 2 2 2005

Ms. Norma LeMay Manager, Regulatory Affairs NxStage Medical, Inc. 439 South Union Street Suite 501 LAWRENCE MA 01843

Re: K053286

K055260
Trade/Device Name: NxStage PureFlow-B Solution Regulation Number: 21 CFR §876.5820 Regulation Name: Hemodialysis system and accessories Regulatory Class: II Product Code: KPO Dated: November 23, 2005 Received: November 25, 2005

Dear Ms. LeMay:

We have reviewed your Section 510(k) premarket notification of intent to maket the device for use attend in We have reviewed your Section Fronty promation in the indications for use stated in
above and have determined the device is substantially equivalent (for the stated in above and nave determined the device is accessions of the state commerce prior to the enclosure) to legally marketcc predical Device Anendments, or to devices that have been May 28, 1976, the enactinent date of the Federal Food, Dugg, and Cosmetic Act (Act) that the reclassified in accordance with the provisions of application (PMA). You may, therefore, market the A do not require approval of a prematics approval approvations (The general controls provisions of the Act device, subject to the general controls provisions of devices, good manufacturing practice, labeling, metade requires 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 classified (see above) micelar existing major regulations affecting your Approval), if may be subject to such additions, Title 21, Parts 800 of 898. In addition, FDA
device can be found in the Code of Federal Regulations, Title 21, Parts 800 nove device can be found in the Code of Footerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that Please be advised that FDA STISualles of a substances with other requirements of the Act of all FDA has made a decemmation mar your do rout we frederal agencies. You must comply with all the Federal statutes and regulations administered of other and listing (21 CFR Part 807); labeling (4) Act's requirements, including, but not mined to regultements as set forth in the quality systems (QS)
(21 CFR Part 801); good manufacturing practice requirements as set forcu (21 CFR Part 801); good manufacturing practice requires.
regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act), 21 CFR 1000-1050.

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This letter will allow you to begin marketing your device as described in your Section 510(k)
. This letter will allow you to ocgn marketing your antial equivalence of your device to a legally
premarket notification. The FDA finding of substantial equivals and thus, pe premarket notification. The FDA miding of substantial or your device 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), pleased
ation in the may be and the fill of the first anymbers, becad on the reg If you desire specific advice for your device on our laborating any in the regulation number at the top of this letter:

21 CFR 876.xxxx	(Gastroenterology/Renal/Urology)	240-276-0115
21 CFR 884.xxxx	(Obstetrics/Gynecology)	240-276-0115
21 CFR 892.xxxx	(Radiology)	240-276-0120
Other		240-276-0100

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Also, please note the regulation entitled, "Misoration on your responsibilities under the Act from the 807.97). You may obtain other general information on John September Assistance at its toll-free number (800) Division or (301) 443-6597 or at its Internet address http://www.fda.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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Ko53286

Indications for USE

310ik) Number (if known):

ිevice Name: .

...

NxStage PureFlow-B Solution

m.lications for User

NxStage PureFlow-B Solution is indicated for use with renal replacement therapy systems that utilize sterile premixed dialysate during hemodialysis.

Prescription Use _____________________________________________________________________________________________________________________________________________________________ (Part 21 CFR 801 Subpart D)

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ANDIOR

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 A. Legum

(Division Sign-Off) Division of Reproductive, Abdominal and Radiological Devices 510(k) Number

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Regulation Number and Section

§ 876.5820 Hemodialysis system and accessories.

(a)
Identification. A hemodialysis system and accessories is a device that is used as an artificial kidney system for the treatment of patients with renal failure or toxemic conditions and that consists of an extracorporeal blood system, a conventional dialyzer, a dialysate delivery system, and accessories. Blood from a patient flows through the tubing of the extracorporeal blood system and accessories to the blood compartment of the dialyzer, then returns through further tubing of the extracorporeal blood system to the patient. The dialyzer has two compartments that are separated by a semipermeable membrane. While the blood is in the blood compartment, undesirable substances in the blood pass through the semipermeable membrane into the dialysate in the dialysate compartment. The dialysate delivery system controls and monitors the dialysate circulating through the dialysate compartment of the dialyzer.(1) The extracorporeal blood system and accessories consists of tubing, pumps, pressure monitors, air foam or bubble detectors, and alarms to keep blood moving safely from the blood access device and accessories for hemodialysis (§ 876.5540) to the blood compartment of the dialyzer and back to the patient.
(2) The conventional dialyzer allows a transfer of water and solutes between the blood and the dialysate through the semipermeable membrane. The semipermeable membrane of the conventional dialyzer has a sufficiently low permeability to water that an ultrafiltration controller is not required to prevent excessive loss of water from the patient's blood. This conventional dialyzer does not include hemodialyzers with the disposable inserts (Kiil type) (§ 876.5830) or dialyzers of high permeability (§ 876.5860).
(3) The dialysate delivery system consists of mechanisms that monitor and control the temperature, conductivity, flow rate, and pressure of the dialysate and circulates dialysate through the dialysate compartment of the dialyzer. The dialysate delivery system includes the dialysate concentrate for hemodialysis (liquid or powder) and alarms to indicate abnormal dialysate conditions. This dialysate delivery system does not include the sorbent regenerated dialysate delivery system for hemodialysis (§ 876.5600), the dialysate delivery system of the peritoneal dialysis system and accessories (§ 876.5630), or the controlled dialysate delivery system of the high permeability hemodialysis system § 876.5860).
(4) Remote accessories to the hemodialysis system include the unpowered dialysis chair without a scale, the powered dialysis chair without a scale, the dialyzer holder set, dialysis tie gun and ties, and hemodialysis start/stop tray.
(b)
Classification. (1) Class II (performance standards) for hemodialysis systems and all accessories directly associated with the extracorporeal blood system and the dialysate delivery system.(2) Class I for other accessories of the hemodialysis system remote from the extracorporeal blood system and the dialysate delivery system, such as the unpowered dialysis chair, hemodialysis start/stop tray, dialyzer holder set, and dialysis tie gun and ties. The devices subject to this paragraph (b)(2) are exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 876.9.