K050525 · Nxstage Medical, Inc. · KDI · Jun 24, 2005 · Gastroenterology, Urology
Device Facts
Record ID
K050525
Device Name
NXSTAGE SYSTEM ONE
Applicant
Nxstage Medical, Inc.
Product Code
KDI · Gastroenterology, Urology
Decision Date
Jun 24, 2005
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 876.5860
Device Class
Class 2
Attributes
Therapeutic
Indications for Use
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 Story
NxStage System One is an electro-mechanical hemodialysis system comprising a cycler and a single-use extracorporeal blood/fluid circuit cartridge. Device performs hemofiltration, hemodialysis, and ultrafiltration. Used in acute/chronic care facilities and home environments. Operated by trained, qualified personnel under physician prescription. System manages extracorporeal blood flow and fluid removal; output allows clinicians to manage renal failure and fluid overload. Home use enables patient treatment outside traditional clinical settings, potentially improving access to care.
Clinical Evidence
Prospective clinical study of 32 subjects (ITT population) across six sites. Compared home hemodialysis performance against in-center treatment (each patient as own control). Primary endpoints: ability to deliver prescribed therapy and incidence of adverse events. Results supported substantial equivalence in efficacy, accuracy, and safety for home use.
Technological Characteristics
Electro-mechanical cycler with single-use extracorporeal blood circuit/fluid management cartridge. High permeability hemodialysis system (21 CFR 875.5860). No changes to technological characteristics from predicate.
Indications for Use
Indicated for patients with acute or chronic renal failure or fluid overload requiring hemofiltration, hemodialysis, or ultrafiltration. Use permitted in acute/chronic care facilities or home settings. Requires physician prescription and observation by a trained, competent individual.
Regulatory Classification
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).
Special Controls
*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.”
{0}------------------------------------------------
## 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 501<br>Lawrence, MA 01843 |
| Phone: | (978) 687-4700 |
| Fax: | (978) 687-4800 |
| Contact Person: | Norma LeMay<br>Manager, 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 CFR<br>875.5860, (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.
{1}------------------------------------------------
## 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:
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.
### 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.
{2}------------------------------------------------
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.xxxx<br>21 CFR 884.xxxx<br>21 CFR 892.xxxx<br>Other | (Gastroenterology/Renal/Urology)<br>(Obstetrics/Gynecology)<br>(Radiology) | 240-276-0115<br>240-276-0115<br>240-276-0120<br>240-276-0100 |
|----------------------------------------------------------------|----------------------------------------------------------------------------|--------------------------------------------------------------|
|----------------------------------------------------------------|----------------------------------------------------------------------------|--------------------------------------------------------------|
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
{4}------------------------------------------------
#### INDICATIONS FOR USE
K050525
NxStage System One
510(k) Number (if known):
Device Name:
Indications for Use:
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.
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
Two short videos show you everything — or skip straight to the written tutorial if you'd rather read. You can reopen this any time from the Tutorial button in the top bar.
Part 1 — Search, results, and everyday workflows 16 min
Part 2 — Embeddings: the galaxy map 3 min
1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
Use the checkboxes above the results to narrow: SaMD keeps only software-only devices, AI / ML keeps only devices with AI.
Exact vs. fuzzy search: what's the difference?
Exact matches on the literal phrase (prefix search works, suffix does not). Fuzzy matches on the meaning and intent of the phrase rather than the exact words. Hover over the badge on any row to see why it matched.
You search "coronary artery calcification" and want only software devices with AI. What two filters do you apply?
Narrow by SaMD (software-only devices), then narrow by AI/ML (devices with AI).
2. The results table
Scroll right in the results table. The intended use is extracted for you — no need to open the PDF. The device story gives a high-level snapshot of what the device does and how it's used. The AI Performance sub-table shows each output name, acceptance criteria, observed values, and development/test dataset descriptions — the same format Innolitics uses for regulatory strategy outputs, and the fastest high-level fingerprint of an AI device. It is AI-generated but has been very reliable in practice.
Where do you find a device's intended use without opening the PDF?
Scroll right in the search results table. The intended use column is extracted for you; no need to dig into the 510(k) summary PDF.
What does the AI Performance sub-table show, and why is it useful?
Output name, acceptance criteria, observed values, development dataset description, and test dataset description. It's the same format we use for regulatory strategy output and Fast 510(k) input, and the fastest high-level fingerprint of an AI device. AI-generated but reliable in practice.
3. Judging fuzzy relevance
Fuzzy results trail off in relevance as you scroll. Use three signals to decide how far down to go: the fuzzy badge explanations, the intended use column, and whether your target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, you're past the relevant zone. A top hit with a low score (~0.4) and a stretched explanation is a hint the closest predicates are far away — the project may be headed for De Novo. Note the fuzzy search is a pattern match: it doesn't handle negation ("not") well, and hardware devices can appear — filter by SaMD/AI ML to cut them.
How do you judge how far down fuzzy search results to go?
Use the relevancy signals: the fuzzy badge explanations, the intended use column, and whether the target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, results are trailing off in relevancy.
4. Device detail page: chat and citations
Click a device name to open its detail page: device facts on the left, a chat window on the right. Ask something like "Describe the training data". The answer carries little citation bubbles — click one to jump to the highlighted passage in the source PDF, so you can verify every AI answer against the document. There's also a Download PDF button for sharing.
How do you verify an AI chat answer on the device detail page?
Click the citation bubbles to jump to the relevant highlight in the source document.
Reading rule for every project: how many summaries do you read in full?
At least the three most relevant 510(k) or De Novo summaries, in full. After that, use targeted chat questions to confirm your memory quickly. The tool supports this professional habit — it doesn't replace it.
5. Side-by-side comparison
Select multiple rows in the results table (aim for under ~10), then open the PDF Viewer tab. Ask one question — it goes to all selected devices in parallel, each with citations. This is the fastest way to compare and contrast devices: training data, PCCP scope, how they handled adding new scanners, and so on.
What does the side-by-side PDF viewer mode do?
Select multiple devices, open the PDF viewer tab, and ask one question (e.g., "Describe the training data"). It queries all selected devices simultaneously with citations, so you can compare and contrast quickly.
6. Collections
With rows selected, go to the Collections tab and create a labeled collection (e.g., "Cobb Angle Project"). Reload that selection any time — before a client call, pull up the collection and ask questions across all of its devices at once.
How do you save a set of selected devices for later use?
Select the rows, go to the Collections tab, and create a labeled collection (e.g., "Cobb Angle Project"). You can reload the selection anytime and carry it into the PDF viewer and other tabs that support selections.
7. Product codes and the regulations tree
Click a product code in the results to jump to it in the regulations tree — identification text, sibling product codes, and devices you can open in a PDF viewer on the right. Click a regulation number to see its identification, special controls, and related product codes. You can also search by product code or regulation number at the top of the tree. Always read the special controls if any exist for your device — it broadens your search and sharpens pre-kickoff research.
What can you do from the regulations tree view?
Browse product codes and regulation numbers, read the identification text and special controls, browse sibling product codes, open device PDFs on the right, and search by product code or regulation number at the top of the tree.
8. Chart view
Click Show Chart and segment by regulation number (or product code) to see which regulations dominate your result set. Clicking a regulation takes you into the regulations tree. Great for spotting that most matches are, say, hardware laparoscopic devices — a cue to go back and filter.
How do you see which regulations dominate a search result set?
Click "Show Chart" and segment by Regulation Number. Clicking a regulation takes you to the regulations tree.
9. The predicate graph
Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
In the predicate graph, why are commonly predicated devices worth reading?
A lot of people predicated them for a reason. Clicking a node traces parents and children, and selections from search carry over pre-selected.
10. Embeddings: the galaxy map
The Embeddings tab plots every matching document in a 2-D "galaxy map" where semantically similar devices cluster together. Hover or click clusters to explore, and let AI label the clusters for you. Embeddings beat product codes for grouping: two devices can carry different product codes (LLZ vs. QIH) yet do the same thing — the embedding captures the meaning of the intended use and device story. This is also exactly how retrieval-augmented generation (RAG) works under the hood, and it makes a great visual on client calls.
Try it yourself
Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.