The Radixact Treatment Delivery System is indicated for the delivery of radiation therapy stereotactic body radiotherapy (SBRT), or stereotactic radiosurgery (SRS) to tumors or other targeted tissues anywhere in the body under the direction of a licensed medical practitioner. The megavoltage x-ray radiation is delivered using rotational, intensitymodulated (IMRT), or non-modulated (non-INRT/three-dimensional conformal) treatment techniques and using imageguided (IGRT) or non-image-guided workflows in accordance with the physician-approved plan. The Radixact Treatment Delivery System integrates Surface Guided Radiation Therapy (SGRT) for patient position and motion monitoring, and breath-hold gating.

Device Description

The predicate and modified Radixact Treatment Delivery Systems are radiation therapy delivery systems, that provide megavoltage CT imaging capabilities coupled with x-ray radiation delivery. The system achieves delivery using rotational, intensity modulated (IMRT), or non-modulated (non-IMRT/three-dimensional conformal) radiation therapy treatment techniques utilizing image-guided (IGRT) or non-image-guided workflows, to tumors or other targeted tissues anywhere in the body, in accordance with the physician-approved plan.

The additional feature update: VitalHold incorporates an external optical monitoring system (EMS), which is integrated with the Radixact system to enable Surface Guided Radiotherapy (SGRT) for patient setup, patient position and motion monitoring, and breath-hold gating.

Neither the predicate Radixact Treatment Delivery System nor the modified Radixact Treatment Delivery System diagnose disease or quantify treatment effectiveness. Accordingly, they are not intended for diagnostic use.

AI/ML Overview

The provided text describes a 510(k) premarket notification for the Radixact Treatment Delivery System, which is a medical device for radiation therapy. The submission focuses on the substantial equivalence of the modified device to a legally marketed predicate device.

It's crucial to understand that this document does not describe a study involving AI-driven diagnostic or treatment planning software that requires complex acceptance criteria based on human expert review, high-volume datasets, or MRMC studies. Instead, it describes a hardware and software update to an existing radiation therapy delivery system, primarily the integration of a Surface Guided Radiotherapy (SGRT) system for patient positioning and motion monitoring, and breath-hold gating.

Therefore, many of the requested elements regarding acceptance criteria for AI performance (like sensitivity, specificity, MRMC studies, large training/test sets for AI, expert readers for ground truth, and adjudication methods) are not applicable to this type of device submission as described in the provided text.

The "Performance Data" section primarily addresses engineering verification and validation, compliance with electrical safety and EMC standards, and risk management. The "Non-Clinical Data" section focuses on testing the functionality of the SGRT integration with the core Radixact system, not AI performance. It states "No animal or clinical tests are being submitted to establish substantial equivalence with the predicate device."

Here's a breakdown of the requested information based on the provided text, indicating where information is present and where it is not applicable or not detailed for this type of device:

Acceptance Criteria and Study for Radixact Treatment Delivery System (K223159)

This submission is for a modification to an existing radiation therapy delivery system, primarily focusing on the integration of a Surface Guided Radiotherapy (SGRT) system for patient positioning and motion monitoring, and breath-hold gating. The "study" described is primarily engineering verification and validation testing to demonstrate the device's functionality, safety, and effectiveness, not a clinical trial or an AI performance study as typically understood for diagnostic support systems.

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

The document lists "Key system performance attributes" related to the SGRT integration and states that "The Verification results show that the design goals and objectives had been met." However, it does not provide a quantitative table of specific acceptance criteria values and reported performance values beyond stating that the tests demonstrated conformity to design specifications and met user needs. The performance attributes mentioned are functional:

Acceptance Criteria (Functional)	Reported Device Performance (as stated)
1. Track a moving surrogate	"Verification results show that the design goals and objectives had been met." "Data within this submission... include data, discussion, and results." (Implying successful tracking)
2. Deliver treatment beam to the surrogate	"Verification results show that the design goals and objectives had been met." (Implying successful beam delivery in relation to the surrogate)
3. Pause the treatment beam when the surrogate has moved out of a defined threshold, i.e., gating window	"Verification results show that the design goals and objectives had been met." (Implying successful pausing when out of threshold)
4. Inform the user to resume the treatment beam when the surrogate moves within the defined threshold	"Verification results show that the design goals and objectives had been met." (Implying successful user notification for resumption)
Overall Safety and Effectiveness	"The modified Radixact Treatment Delivery System meets the safety and performance criteria and is substantially equivalent with reference to safety and effectiveness to the predicate Radixact Treatment Delivery System." "The enhanced ability to turn the MV beam on in under one second."
Compliance with Standards	Conforms to listed electrical safety, EMC, radiation protection, and usability standards (e.g., ANSI AAMI ES60601-1, IEC 60601-1-2 Ed 4.1, IEC 60601-2-1 Ed 3.1) and regulatory references (21 CFR §820, ISO 13485, ISO 14971).

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

Test Set Sample Size: Not specified in terms of patient cases or images for performance testing. The "Non-Clinical Data" section refers to "testing outlined above" (functional tests with a "moving surrogate"), which are likely engineering tests rather than patient studies.
Data Provenance: Not applicable in the context of patient data for a test set. The validation is primarily technical/engineering.

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

Not Applicable. This submission does not involve AI-driven diagnosis or analysis requiring expert interpretation of medical images to establish ground truth for a test set. The "ground truth" for the functional tests would be the controlled movement of the surrogate and the expected system response, not expert consensus on clinical data.

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

Not Applicable. There are no medical image interpretations requiring adjudication for this device's submission as described.

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

No Multi-Reader Multi-Case (MRMC) study was done. The document explicitly states: "No animal or clinical tests are being submitted to establish substantial equivalence with the predicate device." This device is a treatment delivery system, not a diagnostic AI system intended to assist human readers in interpretation.

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

The performance evaluation focused on the integrated system's functional capabilities (tracking, beam delivery, pausing, informing user). While the SGRT system itself performs some automated actions (e.g., gating the beam), the evaluation is of its function within the treatment delivery workflow, not as a standalone AI algorithm producing outputs for human review. The document does not describe "algorithm only" performance as a separate study element in the context of an AI-driven system.

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

Type of Ground Truth: For the "Key system performance attributes" related to the SGRT, the ground truth would be the controlled and known physical parameters of the moving surrogate (e.g., its position, movement beyond/within thresholds) and the expected system response according to design specifications. This is typical for engineering verification and validation of a mechanical/software system, not clinical ground truth from patient data like pathology or expert consensus.

8. The sample size for the training set

Not Applicable. This document does not describe the development of a machine learning (AI) model with a "training set" in the context of diagnostic or predictive AI. The submission is for a hardware and software update to a radiation therapy delivery system.

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

Not Applicable. As there is no described training set for an AI model, this question is not relevant to the provided text.

Summary

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June 23, 2023

Image /page/0/Picture/1 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). The logo consists of two parts: the Department of Health & Human Services logo on the left and the FDA logo on the right. The FDA logo is in blue and includes the letters "FDA" in a square, followed by the words "U.S. FOOD & DRUG ADMINISTRATION".

Accuray Incorporated % Karla Fields Senior Regulatory Affairs Specialist 1209 Deming Way MADISON WI 53717

Re: K223159

Trade/Device Name: Radixact Treatment Delivery System Regulation Number: 21 CFR 892.5050 Regulation Name: Medical Charged-Particle Radiation Therapy System Regulatory Class: Class II Product Code: IYE Dated: May 23, 2023 Received: May 24, 2023

Dear Karla Fields:

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.

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 803) for

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devices or postmarketing safety reporting (21 CFR 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 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 https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.

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

Image /page/1/Picture/5 description: The image shows a digital signature. The signature is from Lora D. Weidner. The date of the signature is 2023.06.23, and the time is 07:54:07 -04'00'.

Lora D. Weidner, Ph.D. Assistant Director Radiation Therapy Team DHT8C: Division of Radiological Imaging and Radiation Therapy Devices OHT8: Office of Radiological Health 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) K223159

Device Name The Radixact Treatment Delivery System

Indications for Use (Describe)

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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Premarket Notification 510(k) Summary

As required by 21 CFR 807.92

510(k) Number:	K223159
Product Name:	Radixact Treatment Delivery System
Date Prepared:	June 22, 2023
Submitter:	Accuray Incorporated1209 Deming WayMadison, Wisconsin 53717
Primary Contact Person:	Karla Fields(608) 824-2990kfields@accuray.com
Secondary Contact Person:	Michael Preto(608) 405-9427mpreto@accuray.com
Common or Usual Name	Medical Linear Accelerator
Regulation:	21 CFR 892.5050
Classification Name:	892.5050 Medical charged-particle radiation therapy system
Regulatory Class:	II
Product Code:	IYE
Primary Predicate Device:	Radixact Treatment Delivery System, K202412
Reference Device:	Radixact Treatment Delivery System, K182687

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Device Description

The primary predicate Radixact Treatment Delivery System was last cleared on K202412.

Intended Use

The Radixact Treatment Delivery System is intended for the delivery of radiation therapy, stereotactic body radiotherapy (SBRT), or stereotactic radiosurgery (SRS) to tumors or other targeted tissues anywhere in the body under the direction of a licensed medical practitioner. The megavoltage x-ray radiation is delivered using rotational, intensity-modulated (IMRT), or non-modulated (non-IMRT/three-dimensional conformal) treatment techniques and using image-guided (IGRT) or nonimage-guided workflows in accordance with the physician-approved plan.

Indication for Use

The Radixact Treatment Delivery System is indicated for the delivery of radiation therapy, stereotactic body radiotherapy (SBRT), or stereotactic radiosurgery (SRS) to tumors or other targeted tissues anywhere in the body under the direction of a licensed medical practitioner. The megavoltage x-ray radiation is delivered using rotational, non-rotational, intensity-modulated (IMRT), or non-modulated (non-IMRT/three-dimensional conformal) treatment techniques and using image-guided (IGRT) or nonimage-guided workflows in accordance with the physician-approved plan. The Radixact Treatment Delivery System integrates Surface Guided Radiotherapy (SGRT) for patient setup, patient position and motion monitoring, and breath-hold gating.

Significant Differences

The new functionality added to the modified Radixact Treatment Delivery System provides an enhanced user experience. The primary focus of the additional updates within this submission for the modified Radixact Treatment Delivery System are:

To provide integration of a Surface-Guided Radiotherapy (SGRT) system, through an optional interface VitalHold utilized for breath-hold gating capabilities
Switching of the intended use and indications for use statements, to their appropriate descriptors (with the feature update included in this submission)

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The primary function of VitalHold encompasses a licensable feature that integrates a Surface Guided Radiotherapy (SGRT) system through the Accuray Connect - Surface Imaging interface. VitalHold can be used for real-time optical patient setup and to perform breath-hold gating techniques like deep inspirational breath-hold (DIBH) and allows an external system to gate the MV beam during treatment delivery for the purpose of breath-hold gating and/or monitoring of patient positioning during treatment. Note that breath-hold gating can be used to do DIBH, is just one of several clinical techniques that can be delivered by using the breath-hold gating feature. This feature also includes the enhanced ability to turn the MV beam on in under one second.

Summary of Technological Characteristics

The modified Radixact Treatment Delivery System has imaging and treatment capabilities similar to those of the predicate Radixact Treatment Delivery System. It also incorporates a functionally equivalent CT-style gantry and patient couch.

Additionally, the predicate and subject devices have substantially equivalent performance specifications, technological characteristics, and incorporate ClearRT helical kVCT imaging (complementing the feature addition in this submission). Further, the predicate and modified Radixact Treatment Delivery System are comprised of the same fundamental scientific principles and have substantially equivalent principles of operation.

The main difference between the predicate and the subject device is the integration of VitalHold the licensable feature discussed. The Intended Use and Indications for Use have been modified (switching them to their appropriate descriptors) with the Intended Use Statement to be more general and the Indications for Use to be more specific. The feature addition supported by the verification and validation activities, the additional acronyms and specificity added to the Indications for Use are considered minor, as outlined in the table below. Where there are technological differences between the subject and predicate devices, those differences do not raise different questions of safety or effectiveness.

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Device Characteristic	Predicate Device	Subject Device	Comparison
Intended Use	ClearRT Helical kVCT for theRadixact Treatment Delivery System(K202412)	Radixact Treatment Delivery System	Analysis
Intended Use	The kVCT Imaging Feature is anoption within the intended use of theRadixact Treatment Delivery System.The Radixact Treatment DeliverySystem is intended to be used for thedelivery of radiation therapy,stereotactic radiotherapy or stereotacticradiosurgery to tumors or other targetedtissues. The megavoltage x-rayradiation is delivered using rotational,non-rotational, intensity modulated(IMRT), or non-modulated (non-IMRT/three dimensional conformal)treatment techniques and using image-guided (IGRT) or non-image-guidedworkflows in accordance with thephysician-approved plan.	The Radixact Treatment Delivery Systemis intended for the delivery of radiationtherapy, stereotactic body radiotherapy(SBRT) or stereotactic radiosurgery (SRS)to tumors or other targeted tissuesanywhere in the body under the directionof a licensed medical practitioner. Themegavoltage x-ray radiation is deliveredusing rotational, non-rotational, intensity-modulated (IMRT), or non-modulated(non-IMRT/three-dimensional conformal)treatment techniques and using image-guided (IGRT) or non-image-guidedworkflows in accordance with thephysician-approved plan.	Addition of acronyms (features), switchingIntended Use Statement to be more general.
Device Characteristic	Predicate Device	Subject Device	Comparison
Indications for Use	ClearRT Helical kVCT for theRadixact Treatment Delivery System(K202412)	Radixact Treatment Delivery System	Analysis
Indications for Use	The kVCT Imaging Feature is an optionwithin the indications for use of theRadixact Treatment Delivery System.The Radixact Treatment Delivery Systemis indicated for the delivery of radiationtherapy, stereotactic radiotherapy orstereotactic radiosurgery to tumors orother targeted tissues anywhere in thebody under the direction of a licensedmedical practitioner.	The Radixact Treatment Delivery System isindicated for the delivery of radiationtherapy, stereotactic body radiotherapy(SBRT) or stereotactic radiosurgery (SRS) totumors or other targeted tissues anywhere inthe body under the direction of a licensedmedical practitioner. The megavoltage x-rayradiation is delivered using rotational, non-rotational, intensity-modulated (IMRT), ornon-modulated (non-IMRT/three-dimensional conformal) treatment techniquesand using image-guided (IGRT) or non-image-guided workflows in accordance withthe physician-approved plan.The Radixact Treatment Delivery Systemintegrates Surface Guided Radiation Therapy(SGRT) for patient setup, patient positionand motion monitoring, and breath holdgating.	Addition of acronyms (features), switchingIndications for Use Statement to be more specific.Addition of SGRT.The SGRT statement is supported by the VitalHoldfeature updates: incorporating an external opticalmonitoring system (EMS), integrated with theRadixact system for patient setup, patient positionalong with motion monitoring, and breath-holdgating.The optional feature update does not raiseadditional questions of safety and effectivenesssupported by the results of the verification andvalidation activities, the additional acronyms andspecificity.Adding to the Indications for Use is consideredminor.
Device Characteristic	Predicate Device	Subject Device	Comparison
ClassificationRegulation, ProductCode & SystemConfiguration	ClearRT Helical KVCT for theRadixact Treatment Delivery System(K202412)	Radixact Treatment Delivery System	Analysis
Classification,Regulation, ProductCode	§892.5050 Medical charged-particleradiation therapy system, class II, IYE	§892.5050 Medical charged-particleradiation therapy system, class II, IYE	Identical
System Configuration	Stand-alone radiation delivery systemwith kV imaging added (does notinclude data management system orplanning system)	Stand-alone radiation delivery system withClearRT & kV imaging (does not includedata management system or planningsystem) with gated motion management.	Administrative updates. kV Radiographs andMotion Tracking introduced in K182687. kVCTintroduced in K202412. Updates to brandnames. Inclusion of Gated Motion Management.
Radiation Source
Nominal BeamEnergy	6 MV	6 MV	Identical
Fixed Field Size	1.0 cm x 40 cm2.5 cm x 40 cm5.0 cm x 40 cm	1.0 cm x 40 cm2.5 cm x 40 cm5.0 cm x 40 cm	Identical
Dynamic Field Size	1.0 - 2.5 cm x 40 cm1.0 - 5.0 cm x 40 cm	1.0 - 2.5 cm x 40 cm1.0 - 5.0 cm x 40 cm	Identical
Isocenter Distance	850 mm	850 mm	Identical
Dose Rate(standard)	850 cGy/min	850 cGy/min	Identical
Dose Rate (optional)	1000 cGy/min	1000 cGy/min	Identical
Collimation
Primary CollimationMethod	Rectangular, fixed tungsten aperture	Rectangular, fixed tungsten aperture	Identical
Collimation Size(MLC)	40 cm total width	40 cm total width	Identical
CollimationTransition Time(MLC)	< 30 ms (MLC)	< 30 ms (MLC)	Identical
Device Characteristic	Predicate Device	Subject Device	Comparison
MVCT Imaging
Energy/Type(source)	Megavoltage ComputedTomography	Megavoltage Computed Tomography	Identical
Field of View Size	39 cm diameter	39 cm diameter	Identical
Contrast Resolution(FBP-Filtered BackProjection)	3% contrast for 30 mm object orbetter	3% contrast for 30 mm object or better	Identical
Contrast Resolution(ITR-IterativeReconstruction)	2% contrast for 20 mm object orbetter	2% contrast for 20 mm object or better	Identical
Spatial Resolution	1.6 mm (at 3.2 mm intervals)	1.6 mm (at 3.2 mm intervals)	Identical
Dose	1.1 - 3.4 cGy (CTDIvol, Head)0.8 - 2.5 cGy (CTDIvol, Body)	1.1 - 3.4 cGy (CTDIvol, Head)0.8 - 2.5 cGy (CTDIvol, Body)	Identical
Spatial Integrity	1 mm	1 mm	Identical, same capability as original system
kVCT Imaging	ClearRT Helical kVCT for theRadixact Treatment Delivery System(K202412)	Radixact Treatment Delivery System	Analysis
Source	40 - 150 kV Radiography Class I(60601-2-28) X-ray tube assembly	40 - 150 kV Radiography Class I(60601-2-28) X-ray tube assembly	Identical
Field of View (FOV)options	25 - 50 cm	27 - 50 cm	Small adjustment to lower end of the range.Minor differences are negligible and do notresult in different questions of safety oreffectiveness.
Scan Length	Up to 135 cm continuous	Up to 135 cm continuous	Identical.
Imaging Dose	0.6 - 4.3 (CTDIvol, Head)0.4 - 2.3 (CTDIvol, Body)	0.17- 2.6 (CTDIvol, Head)0.21 - 3.1 (CTDIvol, Body)	No changes made, slight differences due to fine-tuning of protocols. The latest measurements forCTDIvol, head were measured for Headprotocols only. CTDIvol, body was measuredfor Thorax, Pelvis, and Whole Body.
Slice Spacing	1.2, 1.8, 3.6 mm	1.2, 1.8, 3.6 mm	Identical.
Spatial Resolution	1.0 mm (at 2.0 mm intervals)	1.0 mm (at 2.0 mm intervals)	Identical.
Image Size	512 x 512 pixels	512 x 512 pixels	Identical.
Device Characteristic	Predicate Device	Subject Device	Comparison
Spatial Integrity	0.5 mm	0.5 mm	Identical.
Low ContrastResolution	1% contrast for 10 mm object (20 cmphantom)2% contrast for 15 mm object (30 cmphantom)	1% contrast for 10 mm object (20 cmphantom)2% contrast for 15 mm object (30 cmphantom)	Identical.
Physical Geometry
Bore size (diameter)	85 cm	85 cm	Identical
Minimum RoomDimensions (HWL)	274.3 x 463 x 602 cm	Approximately 270 x 462 x 602 cm	Substantially equivalent. Minor differences arenegligible.
Patient Couch –Degrees of Freedom	Independent of each of the other axesX: +/- 2.5 cmY: 145 cmZ: at least 2 cm below isocenter	Independent of each of the other axesX: +/- 2.5 cmY: 145 cmZ: at least 2 cm below isocenter	Substantially equivalent. Does not result indifferent questions of safety or effectiveness.
Patient Surface -Biocompatibility(Couch Top)	Carbon-fiber top	Carbon-fiber top and Synchrony vest/fiberoptic assembly	Substantially equivalent. ISO 10993-1compliant. First introduced to Radixact onK182687. Does not result in different questionsof safety or effectiveness.

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Performance Data

The modified Radixact Treatment Delivery System was verified and validated according to the FDA Quality System Regulation (21 CFR §820) and other FDA recognized consensus standards listed below. Test results demonstrate that the device conforms to design specifications and meets of the intended users, including assuring risk mitigations were implemented and functioned properly. Software verification and validation testing were completed and documented in conformance with guidance document Content of Premarket Submissions for Software Contained in Medical Devices (issued May 11, 2005).

Standards

The performance of the modified Radixact Treatment Delivery System has been evaluated and tested for electrical safety and EMC compliance by the independent NRTL test house Intertek Testing Services to the following standards*:

FDARec #	Standard Designation	Short Title
19-4	ANSI AAMIES60601-1:2005/ (R) 2012 and A1:2012,C1:2009/(R)2012 and 2:2010/(R)2012	General requirements for basic safety and essentialperformance
19-36	IEC 60601-1-2 Edition 4.1 2020-09	Electromagnetic Compatibility - Requirements and Tests
12-269	IEC 60601-1-3 Ed. 2.1 2013-04	Radiation Protection in Diagnostic X-ray Equipment.
12-285	IEC 60601-2-1 Ed. 3.1 2014-07	Electron Accelerators in the Range 1 MeV to 50 MeV
12-319	IEC 60601-2-68 Ed. 1.0 2014-09	X-ray-based Image-Guided Radiotherapy Equipment foruse with Electron Accelerators, Light Ion Beam TherapyEquipment and Radionuclide Beam Therapy Equipment
12-307	AAMI RT2:2017	Radiation therapy readiness check
5-89	IEC 60601-1-6 Edition 3.1 2013-10	Usability

Regulatory References

In accordance with the regulatory references containing product requirements, the modified Radixact Treatment Delivery System conforms to the following:

21 CFR §820 Quality System Regulation ●
ISO 13485: 2016 Medical devices - Quality management systems
ISO 14971: 2019 Medical devices Applications of risk management to medical devices ●

Non-Clinical Data

Breath-hold gating is enabled by the integration of Radixact with a Surface Guided Radiotherapy (SGRT) system. The use of an SGRT system with Radixact also provides the clinician with the ability to perform optical setup, and patient surface monitoring during treatment. We described the new features that are added on Radixact and their benefits in treatment of cases are described further in the executive summaries. We also showed the advantages these features have compared to using traditional methods. We discussed the design concept and how the implementation supports the automatic use of Radixact with an SGRT device, in other words, enables this new feature.

Key system performance attributes were evaluated:

1. Track a moving surrogate
1. Deliver treatment beam to the surrogate
1. Pause the treatment beam when the surrogate has moved out of a defined threshold, i.e., gating window
1. Inform the user to resume the treatment beam when the surrogate moves within the defined threshold

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This testing outlined above and included in this submittal has been performed to ensure that we deliver a safe and effective design, hence a safe product. Data within this submission and specifically, the executive summaries, include data, discussion, and results. The Verification results show that the design goals and objectives had been met. These summaries along with raw data within our submission support the feature addition and claim that the modified Radixact Treatment Delivery System is as safe and effective as the predicate device. Therefore, the modified Radixact Treatment Delivery System is substantially equivalent to the predicate device.

Clinical Testing

No animal or clinical tests are being submitted to establish substantial equivalence with the predicate device.

Conclusion

The modified Radixact Treatment Delivery System is substantially equivalent to the predicate Radixact Treatment Delivery System. The intended use and indications for use of the modified Radixact Treatment Delivery System include feature acronyms included with this submission, switching of the Intended Use Statement to be more general, and the Indications for Use Statement to be more specific. A detailed comparison of the similarities and differences between the predicate and modified Radixact Treatment Delivery Systems is provided in this submission. The minor differences between the subject and predicate devices do not raise different questions of safety or effectiveness.

The final results of verification and validation, as well as conformance to relevant safety standards. demonstrate that the modified Radixact Treatment Delivery System meets the safety and performance criteria and is substantially equivalent with reference to safety and effectiveness to the predicate Radixact Treatment Delivery System.

Regulation Number and Section

§ 892.5050 Medical charged-particle radiation therapy system.

(a)
Identification. A medical charged-particle radiation therapy system is a device that produces by acceleration high energy charged particles (e.g., electrons and protons) intended for use in radiation therapy. This generic type of device may include signal analysis and display equipment, patient and equipment supports, treatment planning computer programs, component parts, and accessories.(b)
Classification. Class II. When intended for use as a quality control system, the film dosimetry system (film scanning system) included as an accessory to the device described in paragraph (a) of this section, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 892.9.