The HILZO Esophageal Stents are partially covered and fully covered, self-expanding tubular prosthesis designed to maintain patency of esophageal strictures. The HILZO Esophageal stents are available loaded on two styles of delivery devices, Over the Wire (OTW) and Through the Scope (TTS). The OTW delivery devices are 14Fr and the TTS is 10.5Fr to enable delivery through the working channel of an endoscope. The stents are made of Nitinol wire and are designed to prevent stent migration due to peristaltic motion and tumor in-growth. The stents are available in a variety models, diameters and lengths.

AI/ML Overview

The document provided is a 510(k) Premarket Notification from the FDA for a medical device: the Hilzo Esophageal Stents. This type of submission is for demonstrating "substantial equivalence" to a legally marketed predicate device, not for establishing novel safety and effectiveness through clinical trials or performance studies involving complex metrics like those for AI/ML devices (e.g., sensitivity, specificity, clinical workflow improvement).

Therefore, the vast majority of the requested information regarding acceptance criteria, study design, ground truth establishment, expert adjudication, MRMC studies, and training set details are not applicable to this particular document. This document focuses on demonstrating that the new device is as safe and effective as a previously cleared device, primarily through bench testing comparing physical and mechanical properties, and biocompatibility.

Here's what can be extracted and what cannot:

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

The document provides a comparative table where "acceptance criteria" are implicitly defined by similarity to the predicate device's performance, often with an explicit acceptance range (e.g., "fell within the +/- 5% difference acceptance criteria").

Feature	Acceptance Criteria (compared to Niti-S Esophageal K080782)	Reported HILZO Esophageal Stent Performance Range / Value	Reported Niti-S Esophageal Performance Range / Value
Regulatory Number	Same	878.3610	878.3610
Product Code	Same	ESW	ESW
Indication for Use	Same	For esophageal strictures caused by intrinsic and/or extrinsic malignant tumors	For esophageal strictures caused by intrinsic and/or extrinsic malignant tumors
Principle of Operation	Similar/Same (TTS and OTW models for HILZO, OTW for predicate)	TTS and OTW models available	OTW
Biocompatibility	Biocompatible per ISO 10993	Biocompatible per ISO 10993 (found to be)	Biocompatible per ISO 10993
Single Use	Yes	Yes	Yes
Sterility	Eto	Eto	Eto
Stent material	Nitinol	Nitinol	Nitinol
Covering material	Similar (biocompatibility and mechanical testing support equivalence)	Silicone/PTFE	Silicone
Stent diameter (mm)	Similar (compression & expansion testing support differences)	18-20 mm	16-20 mm
Stent total length (mm)	Similar (compression & expansion testing support differences; context of other cleared stents)	60-150 mm	60-120 mm
Stent head	Similar flaring stent head design	Silicone covered and uncovered flaring stent head design with/without removal string (lasso)	Silicon covered and uncovered flaring stent head design with/without removal string (lasso)
Delivery Diameter	Similar (deployment testing and tensile strength demonstrate performance)	OTW - 14 Fr, 16 Fr; TTS - 10.5 Fr	OTW - 16 Fr and 20 Fr
MR Status	MR Conditional	MR Conditional	MR Conditional
Expansion Force	All results fell within ±5% difference	Range: 0.442-0.537 kgf (Avg.)	Range: 0.439-0.543 kgf (Avg.)
Compression Force	All results fell within ±5% difference	Range: 3.073-3.925 kgf (Avg.)	Range: 3.093-3.914 kgf (Avg.)

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

The document mentions "extensive biocompatibility data" and various "Non-Clinical Performance Testing" types (shelf-life, expansion force, compression force, etc.). However, it does not specify sample sizes for these tests. The data provenance would be that of the manufacturer's internal testing. It's retrospective in the sense that the tests were completed before the submission. No country of origin for specific test data is provided, but the manufacturer is Thoracent, Inc. in Huntington, NY, USA.

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

This is not applicable. For this type of device (a physical medical implant), "ground truth" is established through engineering and biological performance standards, not expert medical opinion on a data set. The device is evaluated on its physical and mechanical properties and biocompatibility.

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

Not applicable. There is no expert adjudication process for bench testing results in the way there would be for image interpretation in an AI/ML study.

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

Not applicable. This is a physical medical device (stent), not an AI/ML diagnostic or assistive software. MRMC studies are used for evaluating the impact of AI on human reader performance for diagnostic tasks.

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

Not applicable. This is a physical medical device, not an algorithm.

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

For this device, "ground truth" is established through:

Engineering specifications and standards: For mechanical properties like expansion and compression force, dimensions, tensile strength, kink resistance.
Biocompatibility standards (e.S. ISO 10993): For biological safety, ensuring the materials are not toxic or harmful to the body.
Sterilization validation: Ensuring the device can be terminally sterilized.
MR safety standards: To determine if the device is safe for patients undergoing MRI.

8. The sample size for the training set

Not applicable. This is a physical medical device, not an AI/ML model that requires a training set.

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

Not applicable. As above, no training set for an AI/ML model exists for this device.

Summary

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Image /page/0/Picture/0 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). The logo consists of two parts: on the left, there is a symbol representing the Department of Health & Human Services-USA, and on the right, there is the text "FDA U.S. FOOD & DRUG ADMINISTRATION" in blue. The text is arranged in three lines, with "FDA" being the largest and boldest, followed by "U.S. FOOD & DRUG" and then "ADMINISTRATION".

January 16, 2024

Thoracent, Inc. % Bosmat Friedman Regulatory Consultant ProMedoss, Inc. 3521 Hatwynn Rd. Charlotte, North Carolina 28269

Re: K223266

Trade/Device Name: Hilzo Esophageal Stents Regulation Number: 21 CFR 878.3610 Regulation Name: Esophageal Prosthesis Regulatory Class: Class II Product Code: ESW Dated: April 26, 2023 Received: April 26, 2023

Dear Bosmat Friedman:

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 (the 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 available 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.

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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.

Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download). Your device is also subject to, among other requirements, the Quality System (OS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30, Design controls; 21 CFR 820.90, Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review, the QS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).

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); medical device reporting of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); 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 Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.

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For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medical-

devices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). 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 (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely,

Sivakami Venkatachalam -S

for

Shanil P. Haugen, Ph.D. Assistant Director DHT3A: Division of Renal, Gastrointestinal, Obesity and Transplant Devices OHT3: Office of GastroRenal, ObGyn, General Hospital, and Urology Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K223266

Device Name Hilzo Esophageal Stents

Indications for Use (Describe)

The HILZO Esophageal Stents are indicated for use in esophageal strictures caused by intrinsic malignant tumors.

X Prescription Use (Part 21 CFR 801 Subpart D)

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

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K223266 Page 1 of 4

510(K) SUMMARY [as required by section 807.92(c)] HILZO Esophageal Stent 510(k) Number K223266

5.1 SUBMITTER

Applicant's Name:

Thoracent, Inc. Brian Lynch, CEO 11 Stewart Ave. Unit 1, Suite 200 Huntington, NY, USA 917-4396742 brian@thoracent.com

Contact Person:

Bosmat Friedman Regulatory Affairs Consultant 3521 Hatwynn Rd. Charlotte, NC 28269 Phone: 980-308-1636 bosmat.f(@promedoss.com

Date Revised:

December 14, 2023

5.2 DEVICE

Trade Name: HILZO Esophageal Stents

Classification Code:	Device:	Prosthesis, Esophageal
	Product Code:	ESW
	Regulation No:	878.3610
	Class:	2
	Medical Specialty:	General & Plastic Surgery
	Review Panel:	Gastroenterology/Urology

5.3 PREDICATE DEVICE

Primary Predicate:

Niti-S Esophageal Stent System, manufactured by Taewoong Medical Co., . Ltd., cleared under K080782; Product Code: ESW

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Reference devices for

. Esophageal TTS Stent, manufactured by Taewoong Medical Co., Ltd., cleared under K123205; Product Code: ESW.
Bonastent Esophageal, manufactured by EndoChoice, Inc. cleared under . K092144: Product Code: ESW

5.4 DEVICE DESCRIPTION

5.5 INDICATIONS FOR USE

The HILZO Esophageal Stents are indicated for use in esophageal strictures caused by intrinsic and/or extrinsic malignant tumors.

5.6 SUBSTANTIAL EQUIVALENCE

The subject and predicate devices are both single- use, partially covered and fully covered esophageal stents indicated for use in esophageal strictures caused by intrinsic and/or extrinsic malignant tumors. The stent weave pattern, delivery devices as well as the available stent sizes are equivalent in design and performance.

Feature	HILZO Esophageal Stent	Niti-S Esophageal (OTW) K080782	Comparison to Predicate
Reg. Number	878.3610	878.3610	Same
Product Code	ESW	ESW	Same
Indication for Use	The HILZO Esophageal Stents are indicated for use in esophageal strictures caused by intrinsic and/or extrinsic malignant tumors	Niti-S Esophageal Stent is intended for use in esophageal strictures caused by intrinsic and/or extrinsic malignant tumors.	Same
Principle of Operation	TTS and OTW models available	OTW	Same as both devices
Biocompatibility	Biocompatible per ISO 10993	Biocompatible per ISO 10993	Same
Single use	Yes	Yes	Same
Feature	HILZO Esophageal Stent	Niti-S Esophageal(OTW)K080782	Comparison to Predicate
Sterility	Eto	Eto	Same
Stent material	Nitinol	Nitinol	Same
Coveringmaterial	Silicone/PTFE	Silicone	Similar; biocompatibility testingsupports the safety and effectivenessprofile of the HILZO Esophageal Stent;literature survey and material tensilestrength testing support the use of PTFEcover material
Stent diameter(mm)	18-20 mm	16 - 20 mm	Same; compression and expansiontesting support the stent diameterdifference
Stent total length(mm)	60-150 mm	60-120 mm	Similar; compression and expansiontesting support the increased stentlength; FDA has cleared otheresophageal stents with a length of 150such as K172813 and K211706
Stent head	Silicone covered and uncoveredflaring stent head designwith/without removal string(lasso)	Silicon covered and uncoveredflaring stent head designwith/without removal string(lasso)	Similar flaring stent head design
DeliveryDiameter	OTW - 14 Fr, 16 FrTTS = 10.5 Fr	OTW - 16 Fr and 20 Fr	Similar; deployment testing and tensilestrength testing demonstrate deliverydevice performance
MR Status	MR Conditional	MR Conditional	Same
Expansion force	Fully Covered:18X60 - Avg. 0.442 kgf18X150 - Avg. 0.443 kgf20X60 - Avg. 0.520 kgf20X150 - Avg. 0.460 kgfPartial Covered:18X60 - Avg. 0.445 kgf18X150 - Avg. 0.446 kgf20X60 - Avg. 0.528 kgf20X150 - Avg.0.537 kgf	Fully Covered:18X60 - Avg. 0.439 kgf18X150 - Avg. 0.443 kgf20X60 - Avg. 0.521 kgf20X150 - Avg. 0.543 kgfPartial Covered:18X60 - Avg. 0.440 kgf18X150 - Avg. 0.448 kgf20X60 - Avg. 0.530 kgf20X150 - Avg.0.542 kgf	Similar; all results fell within the ±5%difference acceptance criteria. Theresults support our SE claim
Compressionforce	Fully Covered:18X60 - Avg. 3.073 kgf18X150-Avg. 3.189 kgf20X60 - Avg. 3.75 kgf20X150 - Avg. 3.844 kgfPartial Covered:18X60 - Avg. 3.097 kgf18X150 - Avg. 3.176 kgf20X60 - Avg. 3.876 kgf20X150 - Avg.3.925 kgf	Fully Covered:18X60 - Avg. 3.093 kgf18X150-Avg. 3.168 kgf20X60 - Avg. 3.786 kgf20X150 - Avg. 3.889 kgfPartial Covered:18X60 - Avg. 3.141 kgf18X150 - Avg. 3.220 kgf20X60 - Avg. 3.875 kgf20X150 - Avg.3.914 kgf	Similar; all results fell within the ±5%difference acceptance criteria. Theresults support our SE claim

The following table provides a comparison with the predicate:

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Any differences in technological characteristics do not raise different questions of safety or effectiveness.

5.7 PERFORMANCE DATA

The following performance data is provided in support of the substantial equivalence determination.

Biocompatibility:

The stent and delivery system underwent extensive biocompatibility data in accordance with guidance document: Use of International Standard ISO 10993-1, "Biological evaluation of medical devices - Part 1: Evaluation and testing within a risk management process". Per the obtained results, the HILZO Esophageal Stent System was found to be biocompatible.

Non-Clinical Performance Testing:

The HILZO Esophageal Stents have undergone and successfully passed the following:

Shelf-life and sterilization validation -
Expansion force testing -
Compression force testing -
Dimensional testing -
-Corrosion testing
-Kink resistance testing
-Tensile strength testing (delivery system)
Tensile strength test (cover material) -
Deployment force and deployment positioning testing -
-Suture Loop Tensile Strength Testing
Radiopacity testing -
MR safety -

5.8 CONCLUSION

The HILZO Esophageal Stents have the same indications for use and technological characteristics as its predicates. Niti-S and Esophageal. The company has provided sufficient comparative testing between the HILZO Esophageal Stents and the predicates, as well as additional pre-clinical bench data to demonstrate our substantial equivalency claim. Consequently, it is clear that the HILZO Esophageal Stents are as safe and effective as their primary predicates without raising any new safety and/or effectiveness concerns.

Regulation Number and Section

§ 878.3610 Esophageal prosthesis.

(a)
Identification. An esophageal prosthesis is a rigid, flexible, or expandable tubular device made of a plastic, metal, or polymeric material that is intended to be implanted to restore the structure and/or function of the esophagus. The metal esophageal prosthesis may be uncovered or covered with a polymeric material. This device may also include a device delivery system.(b)
Classification. Class II. The special control for this device is FDA's “Guidance for the Content of Premarket Notification Submissions for Esophageal and Tracheal Prostheses.”