The Rezūm System is intended to relieve symptoms, obstructions, and reduce prostate tissue associated with BPH. It is indicated for men ≥ 50 years of age with a prostate volume ≥ 30cm³ and ≤ 80cm³. The Rezūm System is also indicated for treatment of prostate with hyperplasia of the central zone and/or a median lobe.

Device Description

The reusable Rezūm Generator is provided with the following reusable components:

Generator
One Power Cord
The Rezūm Delivery Device Kit contains the following disposable components:
One sterile Delivery Device with cable and tubing
One sterile Syringe
One sterile Spike Adaptor
One 50 ml Sterile Water Vial
Additional spike adaptor and syringe accessory is provided as an Accessory Pack.

AI/ML Overview

The provided text describes the Rezūm System, a medical device for treating Benign Prostatic Hyperplasia (BPH), and its clinical studies to support substantial equivalence.

Here's an analysis of the acceptance criteria and the studies that prove the device meets them, based on the provided document:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state "acceptance criteria" as a set of predefined thresholds for clinical outcomes. Instead, it reports the "effectiveness" of the device, primarily measured by the International Prostate Symptom Score (IPSS), and its "safety." The approval for substantial equivalence suggests that the reported performance was deemed acceptable by the FDA.

Metric (Implicit Acceptance Criteria)	Reported Device Performance	Study
Effectiveness (IPSS Improvement)
Significant IPSS improvement	Rapid IPSS improvement observed at 1 month, continuing to improve through 6 months and 12 months.	Rezūm FIM Optimization Study
Consistent IPSS improvement	IPSS improvement consistent with FIM study, persisting through 2-year follow-up. At month 3, 6, 12, and 24, >80% of subjects were responders.	Rezūm I Pilot Study
Superior effectiveness to control	At 3 months, effectiveness was superior to the control group (p < 0.001).	Rezūm II Pivotal Study
Long-term effectiveness	At 6 months, 75% of subjects were responders (p < 0.0001). At 12 months, 77% of subjects were responders (p < 0.0001).	Rezūm II Pivotal Study
Safety (Adverse Events)
No unanticipated adverse events	No unanticipated adverse events.	Rezūm FIM Optimization Study
No unanticipated adverse events	No unanticipated adverse events; most reported AEs related to LUTS symptoms and occurred in acute healing phase.	Rezūm I Pilot Study
No unanticipated adverse events	No unanticipated adverse events. The device was safe (p < 0.0001).	Rezūm II Pivotal Study

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

The "test set" in this context refers to the clinical study populations.

Rezūm FIM Optimization Study:
- Sample Size: 15 subjects (14 with 6 months follow-up data).
- Data Provenance: Single site, specific country not explicitly stated, but likely prospective.
Rezūm I Pilot Study:
- Sample Size: 50 patients (45 enrolled in European sites).
- Data Provenance: 3 centers (two in Europe, one in Latin America). Open label, single arm, prospective.
Rezūm II Pivotal Study:
- Sample Size: 197 subjects (136 randomized to treatment, 61 to control).
- Data Provenance: Blinded, 2:1 randomized placebo-controlled study. Countries not specified, but this is a multi-center, prospective study.

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

The document does not provide details on the number or qualifications of experts involved in establishing the "ground truth" for the clinical studies. For BPH clinical trials, the "ground truth" often relies on objective measures (like prostate volume, flow rates) and patient-reported outcomes (like IPSS), which are standard clinical assessments rather than expert consensus on imaging interpretation.

4. Adjudication Method for the Test Set

The document does not explicitly describe an adjudication method for the test set in the sense of independent review of endpoints or adverse events by a separate committee. However, the Rezūm II Pivotal Study was described as a "blinded" and "randomized placebo control study," which inherently includes methods to minimize bias in data collection and assessment.

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

No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. MRMC studies are typically used to assess the impact of AI on human reader performance in interpreting medical images. The Rezūm System is a therapeutic device, and the studies focused on its direct clinical outcomes compared to a control or baseline, not on enhancing human diagnostic capabilities.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done

Yes, the studies were effectively "standalone" in terms of evaluating the device's performance as a therapeutic intervention. The Rezūm System is a medical device that performs a procedure; its "performance" is its ability to treat BPH and improve patient symptoms, which was assessed directly in the clinical trials without human diagnostic interpretation of an algorithm output being the primary endpoint.

7. The Type of Ground Truth Used

The ground truth for the effectiveness of the Rezūm System was based on:

Patient-reported outcomes: Primarily the International Prostate Symptom Score (IPSS), which measures symptoms associated with BPH.
Clinical outcomes: Reduction in prostate tissue (inferred from the mechanism of action and likely measured, though not detailed as a primary endpoint in the summary), and the occurrence of adverse events.
Clinical assessment: Responders defined by a certain improvement in IPSS.

8. The Sample Size for the Training Set

The document describes clinical studies used to evaluate the device rather than "training" a machine learning algorithm. Therefore, there is no "training set" in the context of AI development. The clinical studies (FIM, Pilot, Pivotal) served as the primary evidence for safety and effectiveness.

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

As there is no "training set" in the context of an AI algorithm, this question is not applicable. The clinical study results were established through direct patient observation, validated questionnaires (IPSS), and medical follow-up as discussed in point 7.

Summary

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Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002

September 12, 2016

NxThera, Inc. % Sew-Wah Tay. Ph.D. Regulatory Consultant Libra Medical, Inc. 8401 73rd Avenue North, Suite 63 Brooklyn Park, MN 55428

Re: K150786 Trade/Device Name: Rezūm System Regulation Number: 21 CFR§ 876.4300 Regulation Name: Endoscopic electrosurqical unit and accessories Regulatory Class: II Product Code: KNS Dated: August 21, 2015 Received: August 24, 2015

Dear Sew-Wah Tay:

This letter corrects our substantially equivalent letter of August 27, 2015.

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. 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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Page 2 - Sew-Wah Tay, Ph.D.

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 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

If vou desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Division of Industry and Consumer Education at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm. Also, please note the regulation entitled. "Misbranding by reference to premarket notification" (21CFR 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 the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

You may obtain other general information on your responsibilities under the Act from the Division of Industry and Consumer Education at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.

Sincerely,

For Division

Douglas Silverstein -S 2016.09.12 16:11:58 -04'00'

Benjamin Fisher, Ph.D. Director Division of Reproductive, Gastro-Renal, and Urological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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DEPARTMENT OF HEALTH AND HUMAN SERVICESFood and Drug Administration	Form Approved: OMB No. 0910-0120Expiration Date: January 31, 2017See PRA Statement below.
-------------------------------------------------------------------------	---------------------------------------------------------------------------------------------------

510(k) Number ( if known )	K150786
Device Name:	Rezūm System
Indications for Use ( describe )	The Rezūm System is intended to relieve symptoms, obstructions, and reduce prostate tissue associated with BPH. It is indicated for men ≥ 50 years of age with a prostate volume ≥ 30cm³ and ≤ 80cm³. The Rezūm System is also indicated for treatment of prostate with hyperplasia of the central zone and/or a median lobe.

Type of Use ( select one or both, as applicable )
X Prescription Use (Part 21 CFR 801 Subpart D)	Over-The-Counter Use (Part 21 CFR 801 Subpart C)

CONTINUE ON A SEPARATE PAGE IF NEEDED

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510(K) SUMMARY (K150786) 1

ADMINISTRATIVE INFORMATION 1.1

Date of Summary Preparation: June 12 2015

1.2 CONTACT INFORMATION

Primary Submission Contact	Sew-Wah Tay, PhDRegulatory Consultant,Libra Medical Inc.
----------------------------	------------------------------------------------------------------

Secondary Submission Contact	Julie Bodmer
	Regulatory Consultant,
	Libra Medical Inc.

1.3 DEVICE INFORMATION

Trade Name	Rezūm System
Common Name	Vapor BPH Ablation Device
Classification Name	Endoscopic electrosurgical unit and accessories
Classification Regulation	876.4300
Class	II
Panel	Gastroenterology/Urology
Product Code	KNS

1.4 510(K) TYPE AND REASON FOR SUBMISSION

This 510(k) is a traditional 510(k) and is submitted to obtain marketing clearance for a new device - the Rezūm System.

1.5 PREDICATE DEVICE

The Rezūm System is substantially equivalent to the Medtronic Prostiva devices (K113380 and K142248).

1.6 DEVICE DESCRIPTION

The reusable Rezūm Generator is provided with the following reusable components:

Generator ●
One Power Cord

The Rezūm Delivery Device Kit contains the following disposable components:

0 One sterile Delivery Device with cable and tubing

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One sterile Syringe
One sterile Spike Adaptor ●
One 50 ml Sterile Water Vial ●

Additional spike adaptor and syringe accessory is provided as an Accessory Pack.

INDICATIONS FOR USE / INTENDED USE 1.7

The Rezum System is intended to relieve symptoms, obstructions, and reduce prostate tissue associated with BPH. It is indicated for men ≥ 50 years of age with a prostate volume ≥ 30cm3 and ≤ 80 cm³. The Rezūm System is also indicated for treatment of prostate with hyperplasia of the central zone and/or a median lobe.

1.8 TECHNOLOGICAL CHARACTERISTICS

The device converts water into vapor outside of the body and the vapor is delivered to the prostate tissue via a needle within the sterile Delivery Device. The vapor ablates the targeted tissue within the prostate via thermal ablation as energy is transferred from the vapor to the prostate tissue.

The amount of vapor delivered is controlled by an RF Generator which also controls the amount of saline flush used to cool the urethra.

1.9 PERFORMANCE DATA

The Rezūm System has been tested to meet the FDA 2010 BPH guidance where applicable for preclinical and clinical testing.

The Rezum System has been tested and meets all its physical and performance specifications on the bench including:

Dimensions ●
Tensile strength tests
Full functional tests
Calories tests
Hardware tests ●
Software verification and validation
Packaging tests
Distribution tests

In addition, the Delivery Device was tested for biocompatibility per ISO 10993-1 for short duration contact with tissue and mucosal membrane (<24 hours). The device is sterilized by ethylene oxide to an SAL 10° level. These performances are similar to that described by the predicate device. The testing showed that the device meets specifications before and after aging indicating that the device is as safe and effective as the predicate device.

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The device has also been tested in 3 clinical studies to evaluate the safety and effectiveness of the Rezum device: 65 patients in the feasibility and pilot open label studies and in a 197 patient randomized placebo controlled study. All these studies showed that the device is safe and effective.

1.10 SUMMARY OF CLINICAL DATA

REZŪM FIM OPTIMIZATION STUDY 1.10.1

Fifteen subjects were enrolled in one site in this study to determine the optimum settings and vapor dosage for the Rezum System. Subjects were evaluated for outcomes, adverse events and prostate and lesion sizes at 1 week, 1 month, 3 months and 6 months.

Fifteen subjects were enrolled and treated in this study with 14 subjects having 6 months follow up data. All procedures were completed successfully and there were no unanticipated adverse event. The outcomes for the subjects were equivalent for the full range of energy tested although the higher energy group exhibited more acute AE. Site reported AE early in the study and was typical for thermal ablation of the prostate. Rapid IPSS improvement was observed at 1 month and continues to be improving through 6 months and 12 months.

REZŪM I PILOT STUDY 1.10.2

This is an open label, single arm study involving 3 centers, two in Europe and one from Latin America. A total of 50 patients were enrolled in this study, 45 of whom were enrolled in the two European sites. Only one energy level was used in this study. The IPSS improvement is consistent with the results from Rezūm FIM Optimization Study and improvements in IPSS persist through the 2 year follow up. At month 3, 6, 12 and 24 months, more than 80% of the subjects treated were responders for all the time period. There were no unanticipated adverse events with most of the reported adverse event related to LUTS symptoms and occurred in the acute healing phase.

REZŪM II PIVOTAL STUDY 1.10.3

This is a blinded, 2:1 randomized placebo control study. 197 subjects were enrolled in this study. 136 subjects were randomized to the treatment arm and 61 were assigned to the control arm. 83.6% of the control subjects crossed over to the treatment arm. The rest of the subjects either did not qualify at the time of the crossover or exited the study.

The primary objective is to establish the safety and effectiveness of the device. On an intention to treat basis, the results showed that the device is safe (p<0.0001). The effectiveness as measured by IPSS. At 3 months, the effectiveness of the Rezum System was superior to the control group (p<0.001). The long term effectiveness was measured at 6 and 12 months by comparing the IPSS to the subjects' baseline. At 6 months, 75% of the subjects were responders (p<0.0001) and at 12 months, 77% of the subjects were responders (p<0.0001).

There were no unanticipated adverse events.

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SUBSTANTIAL EQUIVALENCE 1.11

The Rezūm System is substantially equivalent to the Prostiva Device (K113380/K142248). It has the same intended use for thermal ablation of BPH tissue. The test and clinical data showed that the technological difference between the Rezūm and its predicate do not raise safety and efficacy issues. The Rezum II randomized placebo controlled clinical trial data showed that the device is effective in relieving the symptoms of BPH and does not raise new questions of safety.

1.12 CONCLUSION

Based on the test data and the same intended use, the Rezūm System is found to be substantially equivalent to its predicate.

Regulation Number and Section

§ 876.4300 Endoscopic electrosurgical unit and accessories.

(a)
Identification. An endoscopic electrosurgical unit and accessories is a device used to perform electrosurgical procedures through an endoscope. This generic type of device includes the electrosurgical generator, patient plate, electric biopsy forceps, electrode, flexible snare, electrosurgical alarm system, electrosurgical power supply unit, electrical clamp, self-opening rigid snare, flexible suction coagulator electrode, patient return wristlet, contact jelly, adaptor to the cord for transurethral surgical instruments, the electric cord for transurethral surgical instruments, and the transurethral desiccator.(b)
Classification. Class II (performance standards).