MagnetOs Putty is an implant intended to fill bony voids or gaps of the skeletal system i.e., the extremities, pelvis and posterolateral spine. In the posterolateral spine, MagnetOs Putty must be used with autograft as bone graft extender. In extremities and pelvis, MagnetOs Putty is used alone. These osseous defects may be surgically created of of traumatic injury to the bone and are not intrinsic to the stability of the bony structure. MagnetOs Putty resorbs and is replaced with bone during the healing process.

Device Description

MagnetOs Putty is a synthetic, resorbable and osteoconductive bone void filler for the repair of bony defects, containing 65-75% beta-Tri-Calcium Phosphate (TCP, Ca3(PO4)2) and 25-35% Hydroxyapatite (HA, Ca5(PO4)3OH) granules, premixed with a synthetic polymeric binder that provides cohesion between the granules.

MagnetOs Putty is gamma-sterilized, comes in several sizes in block form and is sterile packaged for single use only.

AI/ML Overview

This is a premarket notification (510(k)) for a medical device (MagnetOs Putty), not an AI/ML powered device. Therefore, the information requested in terms of acceptance criteria, study details, ground truth, and training data is not directly applicable in the format typically used for AI/ML devices.

However, I can extract and present the relevant information from the provided document regarding the device's performance, testing, and basis for substantial equivalence to its predicate devices, as if this were a non-AI medical device submission.

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

The document does not explicitly state "acceptance criteria" in the quantitative terms typically found for AI/ML device performance. Instead, it demonstrates substantial equivalence based on a comparison to predicate devices, supported by various tests. The reported performance is that the device is "equivalent" to the predicate devices.

Acceptance Criterion (Implied)	Reported Device Performance
Chemical composition equivalent to predicate	Demonstrated equivalent chemical composition
Physical properties equivalent to predicate	Demonstrated equivalent physical properties
Biocompatibility in accordance with ISO 10993 series and USP <151>	Assessed using the specified methodologies; no adverse indications or results reported.
Performance in a posterolateral spine fusion animal model equivalent to predicate	Demonstrated equivalent performance to predicate.
Performance as a standalone bone void filler in a critical sized femoral animal model equivalent to predicate	Demonstrated equivalent performance to predicate.
Safety and effectiveness equivalent to predicate devices	Indicated no adverse indications or results; determined to be as safe and effective.

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

Animal Studies: The document mentions "a posterolateral spine fusion animal model" and "a critical sized femoral animal model." It does not specify the exact number of animals used in these studies, nor their country of origin. It is implied these were prospective studies as they were conducted to support the 510(k) submission.
Bench Testing: No "sample size" in the conventional sense is stated for bench tests. These tests are performed on the device material itself.
Data Provenance: Not explicitly stated for either animal studies or bench testing, but likely associated with the manufacturer (Kuros Biosciences B.V., Netherlands) or testing facilities they contracted.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)

This concept of "experts establishing ground truth" is not applicable in this context. The "ground truth" for the device's performance in animal models would be based on histological analysis, imaging, and biomechanical assessments conducted by animal study researchers and pathologists, whose qualifications are not detailed in this summary. For chemical and physical properties, the "ground truth" is derived from established analytical methods.

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

Not applicable. This concept is typically relevant for human reader studies or clinical trials involving subjective human assessment.

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 medical device (bone void filler), not an AI/ML powered diagnostic or therapeutic aid. No human reader studies or AI assistance are involved.

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

Not applicable. This device is not an algorithm. Performance of the device itself was evaluated in bench and animal studies (standalone in terms of the device's function as a biological implant).

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

Biocompatibility: Ground truth is established by adherence to recognized ISO standards (ISO 10993 series) and USP <151>, which define acceptable biological responses.
Chemical/Physical Properties: Ground truth is established by validated analytical methods (XRD, FTIR, NMR, ICP/MS, SEM, SBF immersion, mercury intrusion porosimetry) and comparison to the known properties of the predicate devices.
Animal Studies: Ground truth for performance (e.g., bone fusion, defect repair) would be based on pathological assessment (histology, imaging) and potentially functional outcomes in the animal models, as evaluated by veterinary surgeons and pathologists. The document states "demonstrated that the performance of the subject device was equivalent to that of the predicate," implying direct comparative assessment of these outcomes.

8. The sample size for the training set

Not applicable. This device is not an AI/ML algorithm that requires a training set.

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

Not applicable. See point 8.

Summary

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December 6, 2018

Kuros Biosciences B.V. % Angela Paterson Senior Consultant Compliance Solutions Ltd. Suite 10, Dunswood House, 1 Dunswood Road, Cumbernauld Glasgow, United Kingdom, G67 3EN

Re: K181958

Trade/Device Name: MagnetOs Putty Regulation Number: 21 CFR 888.3045 Regulation Name: Resorbable calcium salt bone void filler device Regulatory Class: Class II Product Code: MQV Dated: November 5, 2018 Received: November 7, 2018

Dear Ms. Paterson:

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/cdrl/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, 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.

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

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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 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 medical devices and radiation-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,

Laurence D. Coyne -S

For Mark N. Melkerson Director Division of Orthopedic Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Form Approved: OMB No. 0910-0120

Expiration Date: 06/30/2020

See PRA Statement below.

Indications for Use

510(k) Number (if known) K181958

Device Name MagnetOs Putty

Indications for Use (Describe)

MagnetOs Putty is an implant intended to fill bony voids or gaps of the skeletal system i.e., the extremities, pelvis and posterolateral spine. In the posterolateral spine, Magnet Os Patty must be used with autograft as bone graft extender. In extremities and pelvis, MagnetOs Putty is used alone. These osseous defects may be surgically created of of traumatic injury to the bone and are not intrinsic to the stability of the bony structure. MagnetOs Putty resorbs and is replaced with bone during the healing process.

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

Prescription Use (Part 21 CFR 801 Subpart D)

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

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FORM FDA 3881 (7/17)

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510(k) Summary

This 510(k) summary is submitted in accordance with 21 CFR Part 807, Section 807.92.

Submitter's Name:

Kuros Biosciences B.V.

Submitter's Address:

Kuros Biosciences B.V. Professor Bronkhorstlaan 10, building 48 3723 MB Bilthoven The Netherlands Tel: +31 307400450

Establishment registration Number

3008147766

Contact person:

Angela Paterson

Telephone +44 (0)7884 274 220

Date prepared:

24th October 2018

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Kuros Biosciences B.V. Traditional 510 (k): For MagnetOs Putty

Device Classification Information:

RegulationNumber	Device Name	Device Class	ProductCode	ClassificationPanel
888.3045	Resorbablecalcium saltbone voidfiller	II	MQV	Orthopedic &Rehabilitation

Device Trade Name:

MagnetOs Putty

Device Common Name:

MagnetOs Putty

Intended Use:

MagnetOs Putty is an implant intended to fill bony voids or gaps of the skeletal system i.e., the extremities, pelvis and posterolateral spine. In the posterolateral spine, MagnetOs Putty must be used with autograft as bone graft extender. In extremities and pelvis, MagnetOs Putty is used alone. These osseous defects may be surgically created or the result of traumatic injury to the bone and are not intrinsic to the stability of the bony structure.

MagnetOs Putty resorbs and is replaced with bone during the healing process.

Summary of substantial equivalence:

MagnetOs Putty is substantially equivalent in indications and design principles to the following legally marketed predicate devices:

General Information
Property	510ksubjectDevice	PrimaryEquivalentDevice	EquivalentDevice
Device Name	MagnetOsPutty	Actifuse	Actifuse ABX
DeviceManufacturer	KurosBiosciencesBV	Baxter	Baxter
510k	No	K082575	K082575
DeviceClassification	II	II	II
Product Code	MQV	MQV	MQV

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Kuros Biosciences B.V. Traditional 510 (k): For MagnetOs Putty

General Information
Property	510k subject Device	Primary Equivalent Device	Equivalent Device
Use Environment	Medical/ Clinical	Medical/ Clinical	Medical/ Clinical

The subject device MagnetOs and predicate devices Actifuse and Actifuse ABX K082575 have the same intended use, the same product classification and product code (MQV).

MagnetOs Putty is substantially equivalent to the predicate devices Actifuse and Actifuse ABX (K082575) with respect to design, structure, materials, mechanism of action, and similar Indications for Use in extremities and pelvis. Actifuse is the primary predicate device used for comparison animal studies.

Between MagnetOs Putty, Actifuse and Actifuse ABX predicate devices, the limited differences are the total porosity, ratio of beta-tricalcium phosphate: Hydroxyapatite, silicate content and the binder formulation. The LEOL binder of MagnetOs Putty has the same temporary function as the binder's predicate device Actifuse ABX (K082575). These aspects do not affect the safety and biocompatibility of MagnetOs Putty because of the identical nature of the building blocks of these materials and the site of application (bone).

Device Description

MagnetOs Putty is a synthetic, resorbable and osteoconductive bone void filler for the repair of bony defects, containing 65-75% beta-Tri-Calcium Phosphate (TCP, Саз(PO4)2) and 25-35% Hydroxyapatite (HA, Cas(PO4)3OH) granules, premixed with a synthetic polymeric binder that provides cohesion between the granules.

MagnetOs Putty is gamma-sterilized, comes in several sizes in block form and is sterile packaged for single use only.

Technological Characteristics

Non-clinical testing data submitted, referenced, or relied upon to demonstrate substantial equivalence included chemical composition, physical properties, biocompatibility, and performance characteristics in accordance with FDA recognized consensus standards and FDA guidance documents as applicable.

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Performance Data

Bench testing and animal data demonstrated that the safety and effectiveness of the MagnetOs putty is equivalent to the predicate devices. A summary is given below.

Biocompatibility Testing

Biocompatibility of the device was assessed using the methodology described in ISO 10993-1, ISO10993-3, ISO 10993-5, ISO 10993-6, ISO 10993-10, ISO10993-11 and USP <151>.

Bench Testing (non-clinical tests)

Material characterization performed included the following:

. chemical composition was analyzed by x-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), Organic Volatile Impurities (OVI)
trace elemental analysis was performed by inductively coupled plasma/mass . spectroscopy (ICP/MS),
surface microstructure and bioactivity were evaluated by scanning electron ● microscopy (SEM) and in vitro surface mineralization study (following immersion in simulated body fluid (SBF)), and
physical properties including porosity by mercury intrusion porosimetry. . dissolution, molecular weight by inherent viscosity (IV).

The analytical characterization demonstrated equivalent chemical composition, physical properties and performance characteristics for the subject MagnetOs Putty and the predicate devices.

Animal Studies

The performance of MagnetOs Putty was compared to that of the predicate devices in a posterolateral spine fusion animal model and as a stand alone bone void filler for repair of defects in a critical sized femoral animal model. The results of the study demonstrated that the performance of the subject device was equivalent to that of the predicate.

The data included in this submission demonstrate substantial equivalence to the predicate devices listed above.

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Kuros Biosciences B.V. Traditional 510 (k): For MagnetOs Putty

Safety and effectiveness

MagnetOs Putty utilizes similar technology currently found in legally marketed predicate devices. Based on testing and comparison with the predicate devices, the MagnetOs Putty indicated no adverse indications or results. It is our determination that the MagnetOs Putty is as safe and effective as the predicate devices and performs within its design specifications and is substantially equivalent to the predicate devices.

Regulation Number and Section

§ 888.3045 Resorbable calcium salt bone void filler device.

(a)
Identification. A resorbable calcium salt bone void filler device is a resorbable implant intended to fill bony voids or gaps of the extremities, spine, and pelvis that are caused by trauma or surgery and are not intrinsic to the stability of the bony structure.(b)
Classification. Class II (special controls). The special control for this device is the FDA guidance document entitled “Class II Special Controls Guidance: Resorbable Calcium Salt Bone Void Filler Device; Guidance for Industry and FDA.” See § 888.1(e) of this chapter for the availability of this guidance.