The Coag-Sense® Prothrombin Time (PT) / INR Monitoring System (Self-Test) is an in vitro diagnostic device that provides quantitative prothrombin time (PT) results, expressed in seconds and INR units. It uses fresh capillary whole blood.

It is intended for use by properly selected and suitably trained patients or their caregivers on the order of the treating physician to monitor patients who are on anticoagulation therapy. Patients should be stabilized on warfarin-type (coumarin) anticoagulation therapy prior to self-testing.

The device is not intended to be used for screening purposes.

For professional users, the Coag-Sense® Prothrombin Time (PT) / INR Monitoring System is an in vitro diagnostic device that provides quantitative prothrombin time (PT) results, expressed in seconds and INR units. It uses fresh capillary whole blood. It is intended for use by health care professional at the point of care to monitor patients who are on warfarin-type (coumarin) anticoagulation therapy.

The device is not intended to be used for screening purposes.

For self-test users, the Coag-Sense® Prothrombin Time (PT) / INR Monitoring System is an in vitro diagnostic device that provides quantitative prothrombin time (PT) results, expressed in seconds and INR units. It uses fresh capillary whole blood.

The device is intended for use by properly selected and suitably trained patients or their caregivers on the order of the treating physician to monitor patients who are on anticoagulation therapy. Patients should be stabilized on warfarin-type (coumarin) anticoagulation therapy prior to self- testing.

The device is not intended to be used for screening purposes.

Device Description

The Coaq-Sense Prothrombin Time (PT)/INR Monitoring System is a portable medical device for the measurement of the Prothrombin Time (PT) using fresh capillary whole blood obtained from a finger stick. The Coag-Sense Prothrombin Time (PT)/INR Monitoring System is a hand held device and directly detects clot formation. The System measures the PT of fresh capillary whole blood using micro-mechanical end point detection. The test is performed by inserting a test strip into the meter and applying a drop of blood to the sample receptacle of the disposable test strip. The test strip contains a rotating, spoked wheel that draws the sample into the reaction well after it is applied to the sample receptacle. The spokes rotate across the path of an infrared light beam and mix the liquid sample with the thromboplastin which is dried in the reaction well. When the sample clots, the clot is picked up by the spokes, interrupting the path of the infrared light beam that is detected by the meter.

The PT test and the result is displayed as International Normalized Ratio (INR) and seconds (PT). The result is date/time stamped and stored in the memory of the meter.

The device is powered by batteries and/or AC adapter. This PT/INR System uses the exact same test and control strip as the predicate devices.

AI/ML Overview

This document describes the Coag-Sense Prothrombin Time (PT)/INR Monitoring System, a medical device for measuring PT/INR using fresh capillary whole blood. The submission aims to establish substantial equivalence to previously cleared predicate devices (K050243 and K093243) for both professional and self-testing use.

Here's an analysis of the acceptance criteria and the study that proves the device meets them:

1. Table of Acceptance Criteria and Reported Device Performance

The document doesn't present a specific table of numerical acceptance criteria with corresponding performance metrics for clinical accuracy or diagnostic performance (like sensitivity, specificity, or agreement with a gold standard). Instead, it discusses the successful completion of various tests against pre-determined acceptance criteria and design specifications.

Acceptance Criteria Category	Description of Acceptance Criteria (Implied)	Reported Device Performance
Bench Testing	Device meets pre-determined acceptance criteria and design specifications for:	Met pre-determined acceptance criteria and design specifications.
	Viral Inactivation	Study performed.
	Cleaning/Disinfection	Study performed.
	Component Testing (power, battery, clock, temp, humidity, memory, comm.)	Performed as intended.
	Drop Test	Performed.
	Vibration Testing	Performed.
	Transit Testing	Performed.
Electrical Safety	Compliance with IEC 61010-1:2010 and IEC 61010-2-101:2015 standards.	Testing performed per applicable sections.
Cybersecurity	Documentation prepared according to FDA Guidance (October 2, 2014).	Documentation prepared.
Software V&V	Software performs as intended, meets acceptance criteria, no negative impact on performance/safety.	Software performed as intended, met acceptance criteria, no negative impact.
Usability	User interface ease of use, overall satisfaction.	100% professional users and 97% self-test users strongly agree satisfied; navigation features easy to use.
Comparison of Strip Lots	Correlation with various standard laboratory tests, no bias across AMR.	Correlate extremely well, no evidence of bias across AMR.
Comparison to Predicate Device	Performance equivalent or better than the currently marketed predicate, no difference in results with identical samples.	No difference in results obtained on the modified meter when compared to the predicate device.

2. Sample Sizes Used for the Test Set and Data Provenance

The document does not explicitly state the sample sizes for the "test set" in the context of clinical performance or accuracy. The tests mentioned (bench, electrical safety, software V&V, usability) are primarily engineering and human factors validations, not clinical trials with patient samples.

Data Provenance: The document does not specify the country of origin for any data or whether the studies were retrospective or prospective. Given the nature of a 510(k) submission for an in vitro diagnostic device, it's highly likely that the "comparison of strip lots" and "comparison to predicate device" studies involved prospective testing of patient or quality control samples.

3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications of Experts

This information is not provided in the document. For an in vitro diagnostic device like a PT/INR monitor, "ground truth" would typically be established by:

For strip lot comparisons: Reference laboratory methods (e.g., automated coagulometers, specific plasma-based PT assays).
For predicate device comparisons: The results from the predicate device itself, or potentially a gold-standard laboratory method the predicate device correlates with.

4. Adjudication Method for the Test Set

This information is not mentioned. Given that this is an IVD device measuring a quantitative value (PT/INR), "adjudication" in the traditional sense (multiple readers reviewing images) would not be directly applicable to the device's output. The "ground truth" would be the reference measurement.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and Effect Size

An MRMC study is not applicable here because the device is an in vitro diagnostic (IVD) measurement device, not an image interpretation AI tool. There's no "human reader" component in using the device that requires assistance from AI; it provides a direct quantitative measurement. Therefore, no effect size of human improvement with AI assistance is reported.

6. If a Standalone (i.e., Algorithm Only Without Human-in-the-Loop Performance) Was Done

The device itself is a standalone measurement system. The "algorithm" is inherent in its electromechanical design to detect clot formation and calculate PT/INR. The performance studies described (comparison of strip lots, comparison to predicate) are effectively standalone performance evaluations. The device provides a direct result without human interpretation of raw data.

7. The Type of Ground Truth Used

The document implicitly refers to the following as ground truth/reference for comparative testing:

Standard laboratory tests: Used for calibrating Coag-Sense strip lots and confirming correlation. This implies a highly accurate and established method for measuring PT/INR.
The predicate device: Used as the comparator for the modified Coag-Sense PT/INR meter to demonstrate equivalent or better performance.

This is best characterized as Reference Method Comparison / Comparative Performance Study rather than expert consensus, pathology, or outcomes data.

8. The Sample Size for the Training Set

This information is not specified. The document describes verification and validation studies but does not detail the development process of the device's internal algorithms or any machine learning components that would necessitate a "training set" in the modern AI sense. It's a bio-mechanical and electromechanical system.

9. How the Ground Truth for the Training Set Was Established

As no "training set" (in the context of AI/ML) is explicitly mentioned, the method for establishing its ground truth is also not described. The device's operation is based on physical principles of clot detection rather than learning from a vast dataset.

Summary

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March 4, 2019

CoaguSense, Inc. Robin Bush Director, Regulatory Affairs 48377 Fremont Blvd. Suite #113 Fremont, California 94538

Re: K183255

Trade/Device Name: Coag-Sense Prothrombin Time (PT) / INR Monitoring Device Regulation Number: 21 CFR 864.7750 Regulation Name: Prothrombin time test Regulatory Class: Class II Product Code: GJS Dated: November 19, 2018 Received: November 21, 2018

Dear Robin Bush:

This letter corrects our substantially equivalent letter of February 21, 2019.

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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to 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.

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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 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/CombinationProducts/GuidanceRegulatoryInformation/ucm597488.html; good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm.

For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/) and CDRH Learn (http://www.fda.gov/Training/CDRHLearn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (http://www.fda.gov/DICE) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely,

Leonthena R. Carrington -S

Lea Carrington Director Division of Immunology and Hematology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K183255

Device Name

Coag-Sense® Prothrombin Time (PT) / INR Monitoring System (Self-Test)

Indications for Use (Describe)

The device is not intended to be used for screening purposes.

Type of Use (Select one or both, as applicable)
-------------------------------------------------	--

X Prescription Use (Part 21 CFR 801 Subpart D)

| Over-The-Counter Use (21 CFR 801 Subpart C)

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Image /page/3/Picture/0 description: The image shows the logo for CoaguSense. The logo features a red circle with a gray outline on the left side of the image. The text "CoaguSense" is written in black, with the "Coagu" part of the word in red. The logo is simple and modern.

Appendix S

Date of Summary

December 20, 2018

Type of Submission

Traditional 510(k)

510(k) Applicant

CoaguSense Inc. 48377 Fremont Blvd, Suite 113 Fremont CA, 94538 Phone: 510-270-5442

Primary Contact

Robin Bush Director, Regulatory Affairs 510-270-5442 Email: rbush@coagusense.com

Device Overview

Trade Name:	Coag-Sense Prothrombin Time (PT)/INR Monitoring System
Common Name:	PT/INR Test System
Classification Name:	Prothrombin Time Test
Regulation Number:	§864.7750
Product Code:	GJS

Predicate Device

The predicate devices for this premarket submission:

Trade Name	510(k) Submitter	510(k)Number
Coag-Sense ProthrombinTime (PT)/INR System(Professional Use)	Farallon Medical (CoaguSense Inc.)	K050243
Coag-Sense ProthrombinTime (PT)/INR System(Patient Self-Testing)	CoaguSense Inc.	K093243

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Device Description

The PT test and the result is displayed as International Normalized Ratio (INR) and seconds (PT). The result is date/time stamped and stored in the memory of the meter.

The device is powered by batteries and/or AC adapter. This PT/INR System uses the exact same test and control strip as the predicate devices.

Intended Use / Indications for Use

The same meter and test strip is used for both professional and self-test (home) use.

The device is not intended to be used for screening purposes.

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Image /page/5/Picture/0 description: The image shows the logo for CoaguSense. The logo features the word "CoaguSense" in black and red text. The "Coagu" portion of the word is in red, while the "Sense" portion is in black. The logo also includes a red circle that partially surrounds the word "CoaguSense".

Performance Data

Bench testing, transportation testing, electrical safety testing was performed on the modified Coag-Sense PT/INR Monitoring System, demonstrating that it met the pre-determined acceptance criteria and design specifications.

Bench Testing .
The following bench tests were performed:
Viral Inactivation Study O
Cleaning/Disinfection Study O
Component Testing (including power consumption, battery, clock, temperature, o humidity, memory, communication)
Drop Test O
Vibration Testing O
Transit Testing O
Electrical Safety Testing ●

Testing was performed per the applicable sections of the following electrical safety standards:

IEC 61010-1:2010; Safety requirements for electrical equipment for measurement, o control, and laboratory use - Part 1: General requirements
IEC 61010-2-101:2015; Safety requirements for electrical equipment for o measurement, control, and laboratory use - Part 2-101: Particular requirements for in vitro diagnostic (IVD) medical equipment

Cybersecurity documentation was prepared according to FDA Guidance Content of Premarket Submissions for Management of Cybersecurity in Medical Devices (October 2, 2014).

Software Verification and Validation

Software verification and validation was performed on the functions of the software to ensure that the software performs as intended. Verification and Validation testing of the Coag-Sense PT/INR Monitoring System demonstrated the software performed as intended, met acceptance criteria, and does not have a negative impact on product performance or product safety.

Usablity Testing

A usability study was conducted according to EN 62366 and FDA guidance to verify the changes in user interface. All users agreed or strongly agreed that the navigation features were easy to use. 100% of professional users and 97% of self-test users strongly agree that overall, the modified Coag-Sense meter is satisfactory.

All testing results met the pre-determined acceptance criteria that were established in the test protocols. Based on the testing, the Coag-Sense PT/INR Monitoring System performs as intended, with no new questions of safety or effectiveness identified during testing.

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Image /page/6/Picture/2 description: The image contains the logo for CoaguSense. The logo features a red circle on the left side, with the word "CoaguSense" written in black and red letters to the right of the circle. The word "Coagu" is written in red, while the word "Sense" is written in black. The logo is simple and modern, and it is likely used to represent a company that specializes in coagulation testing.

Testing In Support Of Substantial Equivalence Determination

The design verification testing and design validation testing performed on the modified meter demonstrate the subject device meets defined product specification and intended use. The testing demonstrates that the subject device has comparable performance to the predicate device. The bench testing performed verifies that the subject Coag-Sense PT/INR Monitoring System meets the specified performance specifications and thus, is substantially equivalent to the predicate device for professional and home use.

Comparison of Strip Lots

Comparative studies were performed using Coag-Sense strip lots calibrated against various standard laboratory tests. The studies confirmed Coag-Sensetest strips correlate extremely well, with no evidence of any bias across the AMR.

Comparison to Predicate Device

A side by side comparison study was performed with identical test samples to demonstrate that the performance of the modified Coag-Sense PT/INR meter is equivalent or better than the currently marketed predicate Coaq-Sense PT/INR meter. Performance testing confirmed no difference in the results obtained on the modified meter when compared to the predicate device.

The subject Coag-Sense Prothrombin Time (PT)/INR Monitoring System is substantially equivalent to the cleared predicate (#K050243 and #K093243) with respect to indications for use, intended use, and technological characteristics.

The differences between the subject device and the predicate devices do not raise any new or different issues of safety and effectiveness. Design verification testing confirmed that no new questions of safety or effectiveness were identified during testing, and that the subject Coaq-Sense PT/INR Monitoring System performs as intended.

Conclusion

Based on the comparative analysis, when considering the intended use, principles of operation, performance characteristics and technological characteristics, the Coaq-Sense Prothrombin Time (PT)/INR Monitoring System does not introduce any new questions of safety and effectiveness. The minor differences between the subject Coag-Sense Prothrombin Time (PT)/INR Monitoring System and the predicate device raise no new issues of safety or effectiveness. Therefore, the Coag-Sense Prothrombin Time (PT)/INR Monitoring System is substantially equivalent to the predicate devices.

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).