INRATIO by HEMOSENSE, INC. | FDA 510(k) Summary

The HemoSense INRatio is an in vitro diagnostic system that provides a quantitative prothrombin time results, expressed in seconds and as an International Normalized Ratio (INR). It uses fresh capillary whole blood and is intended for use by health care professionals in monitoring patients who are on warfarin-type (coumarin) anticoagulation therapy. This device is not intended to be used for screening purposes.

Device Description

The INRatio Prothrombin Time Monitoring System uses a modified version of the one-stage prothrombin time test. After a drop of blood is applied to the test strip, it is drawn into the test area and mixed with reagents that cause coagulation to begin. The test area on the test strip is separated into three channels, each of which contains electrodes for detection of the blood clot. One channel contains the reagents to perform the prothrombin time test on the blood sample. The other two channels contain the reagents to run control tests. No external quality control tests are required for the INRatio System. The meter monitors the reactions, and calculates the PT and INR for the blood sample, which are reported on the display. If the control results are not within a set range, it indicates a problem with the test and an error message is reported on the display instead of a result.

AI/ML Overview

The provided document describes the INRatio Prothrombin Time Monitoring System (K020679) and its substantial equivalence to a predicate device, the Roche CoaguChek S. However, it does not provide detailed acceptance criteria and a structured study report with the specific information requested in your prompt.

The document is a 510(k) summary for premarket notification, which focuses on demonstrating substantial equivalence, not necessarily on presenting a comprehensive study report with quantitative acceptance criteria as you've outlined.

Here's a breakdown of what can be inferred or is explicitly stated from the provided text, and what information is missing:

1. Table of Acceptance Criteria and Reported Device Performance:

Acceptance Criteria	Reported Device Performance
Accuracy (compared to predicate and reference method)	"found to be equivalent (r>0.90)"
Precision	"were found acceptable"
Linearity	"were found acceptable"
Interfering Substances	"performed and the results are reflected in the product labeling"
Hematocrit	"performed and the results are reflected in the product labeling"

Missing Information:

Specific quantitative thresholds for "acceptable" precision and linearity. The document only states they were "found acceptable."
Details of the reference method used for accuracy comparison.

2. Sample size used for the test set and the data provenance:

Sample Size: Not explicitly stated for any of the tests (accuracy, precision, linearity).
Data Provenance: The studies were described as "field studies." The country of origin is not specified, but the applicant (HemoSense, Inc.) and the FDA are in the USA. It's not explicitly stated if the data was retrospective or prospective. Given it's a "field study," it's likely prospective data collection for device evaluation.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:

Missing Information. The document does not describe the use of experts to establish ground truth for the test set. The ground truth for Prothrombin Time devices is typically established through a reference laboratory method or a predicate device.

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

Missing Information. No mention of an adjudication method is made.

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 to the INRatio device. The INRatio is an in vitro diagnostic device for quantitative Prothrombin Time measurement, not an AI-assisted diagnostic imaging or interpretation system requiring human readers or affecting their performance. The device directly calculates and reports PT/INR values.

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

Yes, implicitly. The context of the INRatio system, as an in vitro diagnostic device that calculates and displays results, inherently refers to its standalone performance. The accuracy, precision, and linearity tests would assess the device's performance in generating these results independently.

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

For accuracy, the device was compared to the predicate device CoaguChek S and a "reference method." While the specific "reference method" isn't detailed, for PT/INR testing, this typically refers to a laboratory-based coagulation analyzer (e.g., automated photo-optical clot detection instruments). This would be considered a reference laboratory method or a calibrated gold standard.

8. The sample size for the training set:

Missing Information. The document does not discuss a "training set" in the context of machine learning or AI. This device is electro-mechanical and reagent-based, not an AI model that undergoes a training phase.

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

Not applicable. As explained in point 8, there is no "training set" for this type of device.

Summary of Limitations in the Provided Document:

The provided text is a 510(k) summary, which serves to establish substantial equivalence. It highlights key performance aspects like accuracy, precision, and linearity as "acceptable" or "equivalent," but it lacks the granular detail of a full study report (e.g., specific sample sizes for each test, detailed methodology for ground truth establishment, quantitative acceptance criteria thresholds, or raw/processed data). This information would typically be found in the full 510(k) submission, not necessarily in the public summary.

Summary

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K020679

MAY 0 6 2002

Appendix 10. Summary

PREMARKET NOTIFICATION 510(k) Summary

Introduction:

According to the requirements of 21 CFR 807.92, the following information provides sufficient detail to understand the basis for a determination of substantial equivalence.

1. Submitter's name, HemoSense. Inc. 600 Valley Way address, contact: Milpitas, CA 95035 (408) 719-1393 (phone) (408) 719-1184 (fax)
  Contact person: Judith Blunt Date Prepared: February 28, 2002
1. Device name: Common or usual name: Prothrombin Time Test
  Classification Name: Prothrombin Time Test

Trade or Proprietary Name: INRatio

The Roche CoaguChek STM system: device for testing 3. Predicate device Prothrombin Time and INR in whole blood.
1. Device description: The INRatio Prothrombin Time Monitoring System uses a modified version of the one-stage prothrombin time test. After a drop of blood is applied to the test strip, it is drawn into the test area and mixed with reagents that cause coagulation to begin. The test area on the test strip is separated into three channels, each of which contains electrodes for detection of the blood clot. One channel contains the reagents to perform the prothrombin time test on the blood sample. The other two channels contain the reagents to run control tests. No external quality control tests are required for the INRatio System. The meter monitors the reactions, and calculates the PT and INR for the blood sample, which are reported on the display. If the control results are not within a set

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range, it indicates a problem with the test and an error message is reported on the display instead of a result.

The INRatio is an in vitro diagnostic system that 5. Intended use: provides a quantitative prothrombin time result, expressed in seconds and as an International normalized ratio (INR). It is intended for use by healthcare professionals in monitoring patients who are on warfarin-like (coumarin) anticoagulation therapy. This device is not intended to be used for screening purposes.
The INRatio is substantially equivalent in 6. Comparison to materials, design and intended use to other products predicate device: that measure Prothrombin Time in human blood. Most notably, it is substantially equivalent to the CoaguChek S™, manufactured by Roche Diagnostics. Both products are prothrombin time devices, have the same intended use and serve the same professional, point-of-care market. The HemoSense INRatio and the CoaguChek both measure the reaction of the extrinsic coagulation pathway. Both products measure the elapsed time between the start of the reaction and the formation of fibrin from fibrinogen; the CoaguChek measure fibrin formation via the motion of magnetic particles, while the INRatio measures it via a change in the impedance of the sample.
The accuracy of the INRatio was compared 7. Summary of to the CoaguChek S and a reference method in field Performance data: studies and found to be equivalent (r>0.90). Precision and linearity evaluations were performed on the INRatio and the results were found acceptable. Additional testing on interfering substances, and hematocrit were performed and the results are reflected in the product labeling.

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DEPARTMENT OF HEALTH & HUMAN SERVICES

Image /page/2/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular seal with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter. Inside the circle is a stylized image of three human profiles facing to the right, with flowing lines representing hair or movement.

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

Ms. Judith Blunt Director of Clinical Affairs & Customer Support HemoSense, Inc. 600 Valley Way Milpitas, California 95035

MAY 06 2002

K020679 Re:

Trade/Device Name: INRatioTM Regulation Number: 21 CFR § 864.7750 Regulation Name: Prothrombin Time Test Regulatory Class: II Product Code: GJS Dated: February 28, 2002 Received: March 4, 2002

Dear Ms. Blunt:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, 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 (PMA), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) 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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Page 2

This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for 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 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4588. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the 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 "http://www.fda.gov/cdrh/dsma/dsmamain.html".

Sincerely yours,

Steven Sutman

Steven I. Gutman, M.D., M.B.A. Director Division of Clinical Laboratory Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Appendix 11. Indications for Use Statement

Feb 28, 2002

PREMARKET NOTIFICATION INDICATIONS FOR USE STATEMENT (As required by 21 CFR 807.87(j))

510(K) Number:

Device Name: HemoSense INRatio PT Monitoring System

PLEASE DO NOT WRITE BELOW THIS LINE -- CONTINUE ON ANOTHER PAGE IF NEEDED

Signed:	Judith Blunt
Name:	Judith Blunt
Position:	Director of Clinical Affairs and Product Support
Date:	Feb. 28, 2002

on Bign-Off

510(K) Number

Division of Clinical Laboratory Devices

000564

Regulation Number and Section

§ 864.7750 Prothrombin time test.

(a)
Identification. A prothrombin time test is a device used as a general screening procedure for the detection of possible clotting factor deficiencies in the extrinsic coagulation pathway, which involves the reaction between coagulation factors III and VII, and to monitor patients receiving coumarin therapy (the administration of one of the coumarin anticoagulants in the treatment of venous thrombosis or pulmonary embolism).(b)
Classification. Class II (performance standards).