Partial thickness wounds
Full thickness wounds
Pressure ulcers
Venous ulcers
Chronic vascular ulcers
Diabetic ulcers
Trauma wounds (abrasions, lacerations, partial thickness burns, skin tears)
Surgical wounds (donor sites/grafts, post-Mohs surgery, post-laser surgery, podiatric, wound dehiscence)
Draining wounds

Device Description

All three subject devices of this bundled submission are part of a family of devices manufactured by Kerecis Limited. The subject devices can be seen in Table 1. They are lyophilized, terminally sterilized, fish skin medical devices comprised of biocompatible, resorbable fish skin (Wild North Atlantic Cod) for wound management. The devices are intended for single use only. The devices are applied to the wound bed to maintain a moist wound environment. The primary predicate device is Marigen Wound Extra (K190528) and the additional predicate devices are Kerecis Silicone (K213231), and Kerecis Parvus (K241080). Marigen Wound Extra is commercially available under the names Kerecis MariGen, Kerecis GraftGuide, and Kerecis SurgiClose. Kerecis Silicone is commercially available under the names Kerecis Shield and Kerecis SurgiClose Silicone. For clarity, this submission will refer to the devices under their commercially available names, except when specifically referring to the primary predicate device. This information is also shown in Table 1.
Although the subject devices differ from each other in terms of device indications and dimensional specifications, each one remains physically identical to its primary predicate device, both in design and packaging, as well as for indications for use. The only difference between each subject device and its respective primary predicate device is in the device labeling, with the subject devices having additional rehydration fluid options included in their instructions for use (IFUs).

AI/ML Overview

The provided FDA 510(k) clearance letter and summary describe the acceptance criteria and a study to prove the device meets these criteria. However, it's important to note that this submission is for a modification to an existing device (Kerecis Marigen Wound Extra, Kerecis Silicone, Kerecis Parvus) and not for an entirely novel device. The modification specifically addresses the inclusion of additional rehydration fluids. Therefore, the "study" is focused on verifying the device's performance with these new rehydration fluids, rather than establishing initial clinical effectiveness.

Here's a breakdown of the requested information based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria are implicitly defined by the device's performance with the original rehydration fluid (saline) and the need for the device to perform comparably with the new rehydration fluids. The performance is assessed through specific bench tests.

Acceptance Criteria Category	Specific Criteria/Test	Reported Device Performance
Rehydration	Device rehydration with lactated Ringer's solution	Performance remains consistent and comparable to primary predicate devices.
Suture Retention	Device suture retention with autologous body fluid	Performance remains consistent and comparable to primary predicate devices.
General Device Performance	Maintenance of intended use, materials, manufacturing processes, and fundamental scientific technology despite new rehydration fluid options.	Device performance remains consistent and comparable to primary predicate devices, supporting substantial equivalence.

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

The document does not explicitly state the sample size for the rehydration and suture retention tests. It mentions "bench testing" was performed.

Data provenance: Not explicitly stated, but bench testing typically involves laboratory-controlled conditions. It is not patient data from a specific country, nor is it referred to as retrospective or prospective in a clinical trial sense.

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

This type of information (expert consensus for ground truth) is typically associated with clinical studies or diagnostic device clearances where a "truth" is established through expert review of patient data (e.g., radiologist opinions on images). Since this submission focuses on bench testing for a modification to rehydration fluids, this information is not relevant or provided. The "ground truth" here is the prior established performance of the predicate device under saline rehydration.

4. Adjudication Method for the Test Set

Adjudication methods (e.g., 2+1, 3+1) are relevant for studies involving human interpretation or clinical endpoints. As this submission describes bench testing for material and process compatibility, an adjudication method is not applicable and therefore not provided.

5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was done

No, an MRMC comparative effectiveness study was not done. This type of study is typically for diagnostic devices where multiple readers evaluate cases to assess performance with and without AI assistance. This submission is for wound dressings and focuses on physical and biological compatibility with different rehydration fluids.

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

This question is not applicable. The device is a wound dressing, not a software algorithm or an AI-based system. Therefore, there is no "algorithm only" performance to evaluate.

7. The Type of Ground Truth Used

For the specific tests conducted for this modification (rehydration and suture retention with new fluids), the ground truth is implicitly the established performance characteristics of the predicate device when rehydrated with saline. The goal of the new tests was to show that these characteristics are maintained or are comparable when using lactated Ringer's solution and autologous body fluids.

8. The Sample Size for the Training Set

This concept is not applicable as this is not a machine learning or AI device. The "training set" for a traditional medical device would refer to the data used to design and develop the device prior to its initial submission. The summary doesn't provide this detail for the original device development, only that performance testing was "leveraged from the Kerecis primary predicate devices."

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

Again, "training set" and its "ground truth" are terms typically used in AI/ML contexts. For a medical device like a wound dressing, the "ground truth" during initial development (analogous to a training phase) would involve extensive material testing, biocompatibility studies, mechanical property evaluations, and potentially pre-clinical and clinical studies to establish its safety and effectiveness for wound management. The summary indicates that for this modification, the ground truth is based on the previously established performance of the predicate devices.

Summary

U.S. Food & Drug Administration 510(k) Clearance Letter

Page 1

U.S. Food & Drug Administration
10903 New Hampshire Avenue
Silver Spring, MD 20993
www.fda.gov

Doc ID # 04017.08.00

July 16, 2025

Kerecis Limited
Skuli Magnusson
Vice President (Regulatory Affairs, Quality & Clinical Affairs)
Sundastraeti 38, 400 Isafjordur
P.O. Box 151, 400 Isafjordur
Isafjordur, 400
Iceland

Re: K251845
Trade/Device Name: Kerecis® Marigen Wound Extra Autologous Hydration, Kerecis Silicone Autologous Hydration and Kerecis Parvus Autologous Hydration
Regulatory Class: Unclassified
Product Code: KGN
Dated: June 16, 2025
Received: June 16, 2025

Dear Skuli Magnusson:

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.

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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K251845 - Skuli Magnusson Page 2

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 (QS) 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 (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-reporting-combination-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.

All medical devices, including Class I and unclassified devices and combination product device constituent parts are required to be in compliance with the final Unique Device Identification System rule ("UDI Rule"). The UDI Rule requires, among other things, that a device bear a unique device identifier (UDI) on its label and package (21 CFR 801.20(a)) unless an exception or alternative applies (21 CFR 801.20(b)) and that the dates on the device label be formatted in accordance with 21 CFR 801.18. The UDI Rule (21 CFR 830.300(a) and 830.320(b)) also requires that certain information be submitted to the Global Unique Device Identification Database (GUDID) (21 CFR Part 830 Subpart E). For additional information on these requirements, please see the UDI System webpage at https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/unique-device-identification-system-udi-system.

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-devices/medical-device-safety/medical-device-reporting-mdr-how-report-medical-device-problems.

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K251845 - Skuli Magnusson Page 3

For comprehensive regulatory information about medical devices and radiation-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-devices/device-advice-comprehensive-regulatory-assistance/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,

Mustafa A. Mazher -S

For Yu-Chieh Chiu
Assistant Director
DHT4B: Division of Plastic and Reconstructive Surgery Devices
OHT4: Office of Surgical and Infection Control Devices
Office of Product Evaluation and Quality
Center for Devices and Radiological Health

Enclosure

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DEPARTMENT OF HEALTH AND HUMAN SERVICES
Food and Drug Administration

Indications for Use

Form Approved: OMB No. 0910-0120
Expiration Date: 07/31/2026
See PRA Statement below.

510(k) Number (if known) K251845

Device Name
Kerecis® Marigen Wound Extra Autologous Hydration, Kerecis Silicone Autologous Hydration and Kerecis Parvus Autologous Hydration

Indications for Use (Describe)

Kerecis® Marigen Wound Extra Autologous Hydration, Kerecis Silicone Autologous Hydration and Kerecis Parvus Autologous Hydration

Management of wounds including:

Partial thickness wounds
Full thickness wounds
Pressure ulcers
Venous ulcers
Chronic vascular ulcers
Diabetic ulcers
Trauma wounds (abrasions, lacerations, partial thickness burns, skin tears)
Surgical wounds (donor sites/grafts, post-Mohs surgery, post-laser surgery, podiatric, wound dehiscence)
Draining wounds

☑ Prescription Use (Part 21 CFR 801 Subpart D) ☐ Over-The-Counter Use (21 CFR 801 Subpart C)

CONTINUE ON A SEPARATE PAGE IF NEEDED.

This section applies only to requirements of the Paperwork Reduction Act of 1995.

DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.

The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:

Department of Health and Human Services
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FORM FDA 3881 (8/23) Page 1 of 1 PSC Publishing Services (301) 443-6740 EF

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510(k) Summary – K251845

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Premarket Notification Submission (510(k) Summary)

Submitter Information

Sponsor Name: Kerecis Limited
Sponsor Address: Eyrargata 2 – PO Box 151, 400 Isafjordur, Iceland
Sponsor Telephone: +354-419-8000
Establishment Registration: 301060025

Applicant: Skuli Magnusson
Title: VP of Regulatory Affairs, QA & Clinical Affairs
Email Direct: sm@kerecis.com

Primary Contact Person: Skuli Magnusson
Contact Title: VP of Regulatory Affairs, QA & Clinical Affairs
Email Direct: sm@kerecis.com

Date Summary Prepared: July 16, 2025

Device Information

Trade Name (Proprietary): Kerecis® Marigen Wound Extra Autologous Hydration, Kerecis Silicone Autologous Hydration and Kerecis Parvus Autologous Hydration
FDA Device Code: KGN
Categorization: Wound dressing with animal-derived material(s)
Device Class: Unclassified, (Pre-Amendment)

Primary Predicate Device

Company Name: Kerecis
Device Name (Proprietary): Marigen Wound Extra
Device 510(k): K190528

Additional predicate Devices

Company Name: Kerecis
Device Name (Proprietary): Kerecis Silicone
Device 510(k): K213231

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Company Name: Kerecis
Device Name (Proprietary): Kerecis Parvus
Device 510(k): K241080

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Device Description

Table 1: Subject devices of this submission

#	Product Name	510(k) Proprietary Name/Device Name	510(k) Clearance
1	MariGen, GraftGuide, SurgiClose	Marigen Wound Extra	K190528¹
2	Kerecis Shield Adhesive, Kerecis Shield Standard, Kerecis Shield Spiral, Kerecis SurgiClose Silicone	Kerecis Silicone	K213231
3	Kerecis Parvus	Kerecis Parvus	K241080

Although the subject devices differ from each other in terms of device indications and dimensional specifications, each one remains physically identical to its primary predicate device, both in design and packaging, as well as for indications for use. The only difference between each subject device and its respective primary predicate device is in the device labeling, with the subject devices having additional rehydration fluid options included in their instructions for use (IFUs).

Intended Use / Indications for Use

The intended use of each of the subject devices is listed below. No changes to the intended use are proposed in this bundled 510(k) submission.

Product name(s)	Indications for Use
Kerecis MariGen (K190528), Kerecis GraftGuide	Management of wounds, including: • Partial-thickness wounds

¹ K132343 (Marigen Wound Dressing) was the initial submission covering the products now included in the more recent K190528 submission, which introduced additional size variants.

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Product name(s)	Indications for Use
(K190528), Kerecis SurgiClose (K190528), Kerecis Shield variants (K213231), Kerecis SurgiClose Silicone (K213231), and Kerecis Parvus (K241080).	• Full-thickness wounds• Pressure ulcers• Venous ulcers• Chronic vascular ulcers• Diabetic ulcers• Trauma wounds (abrasions, lacerations, partial thickness burns, skin tears)• Surgical wounds (donor sites/grafts, post-Mohs surgery, post-laser surgery, podiatric, wound dehiscence)• Draining wounds

Description of Modification

The only modification from the primary predicate device is in the device labeling. The modification that triggered this submission is the inclusion of additional rehydration options in the instructions for use (IFU). In addition to saline (which is the rehydration fluid in the primary predicate devices), lactated Ringer's solution and autologous body fluids are being added as potential rehydration fluid options for the subject devices of this submission.

Kerecis is implementing this modification in response to interest within the field regarding the use of these fluids for device rehydration.

Technological characteristics and substantial Equivalence

The technological characteristics of the subject devices of this submission and the primary predicate devices (K190528, K213231, K241080), are identical to each respective primary predicate device, to that described in their respective submissions in that they are all animal-based products suitable for the management of multiple types of wounds. They also share identical device design and principle of operation, respectively. The following items are provided to demonstrate substantial equivalence to the primary predicate devices:

Risk analysis summary
Sterilization justification
Shelf-life justification
Biocompatibility justification
Bench testing

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Table 2: Substantial Equivalence comparison table.

Device name	MariGen, GraftGuide, SurgiClose, SurgiClose Silicone, Shield, and Parvus (Subject Devices)	Predicate Devices all with the same names as the Subject Devices (Predicate Devices)	Comparison
Manufacturer	Kerecis Limited	Kerecis Limited	N/A
510(k)	K251845 (Bundled)	K190528 (primary predicate)K213231 (additional predicate)K241080 (additional predicate)	N/A
Prescription, single use only	Yes	Yes	Same
Product Code	KGN (Bundled Submission)	KGN	Same
Indications for Use	The management of wounds including:• Partial-thickness wounds• Full-thickness wounds• Pressure ulcers• Venous ulcers• Chronic vascular ulcers• Diabetic ulcers• Trauma wounds (abrasions, lacerations, partial thickness burns, skin tears)• Surgical wounds (donor sites/grafts, post-Mohs surgery, post-laser surgery, podiatric, wound dehiscence)• Draining wounds	The management of wounds including:• Partial-thickness wounds• Full-thickness wounds• Pressure ulcers• Venous ulcers• Chronic vascular ulcers• Diabetic ulcers• Trauma wounds (abrasions, lacerations, partial thickness burns, skin tears)• Surgical wounds (donor sites/grafts, post-Mohs surgery, post-laser surgery, podiatric, wound dehiscence)• Draining wounds	Same
Materials	Atlantic Cod Fish Skin, Atlantic Cod Fish Skin + Silicone Film Layer	Atlantic Cod Fish Skin, Atlantic Cod Fish Skin + Silicone Film Layer	Same
Supplied sterile?	Yes	Yes	Same

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Device name	MariGen, GraftGuide, SurgiClose, SurgiClose Silicone, Shield, and Parvus (Subject Devices)	Predicate Devices all with the same names as the Subject Devices (Predicate Devices)	Comparison
Sterilization Method	Ethylene Oxide	Ethylene Oxide	Same
Intended for single use?	Yes	Yes	Same
Rehydration Fluid	All Devices in the bundle: Sterile saline, sterile lactated Ringer's solution and autologous body fluids	All Devices in the bundle: Sterile Saline	Different

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Performance Testing

Performance testing for this 510(k) submission was largely leveraged from the Kerecis primary predicate devices, as the subject devices share the same intended use, materials, and manufacturing processes. As a result, additional performance testing was not required, except for rehydration and suture retention tests using autologous body fluid. These specific tests were conducted to address the only modification for the subject devices, i.e., the inclusion of lactated Ringer's solution and of autologous body fluids as rehydration agents. The results confirmed that device performance remains consistent and comparable to the primary predicate devices, supporting a determination of substantial equivalence.

Conclusion

For the purposes of determining substantial equivalence under section 513(i) of the FD&C Act (21 U.S.C. § 360c(i)), the Kerecis® Marigen Wound Extra, Kerecis Silicone, and Kerecis Parvus devices (the subject devices) share the same intended use, functions, mode of action, and fundamental scientific technology as their respective primary predicate devices. Additionally, the subject devices are composed of the same materials and are manufactured using identical processes as the primary predicate devices. The modification is the inclusion of lactated Ringer's solution and of autologous body fluids as optional rehydration fluids in the devices' Instructions for Use (IFUs). Because there are no changes to the fundamental scientific technology or intended use, and verification and validation activities have been completed, there is sufficient evidence to demonstrate that the subject devices perform comparably to the primary predicate devices currently marketed for the same intended use.

It is concluded that the bundled subject device is substantially equivalent to the primary predicate devices.

Regulation Number and Section

N/A