K250584 · Boston Scientific Corporation · KNS · Jun 11, 2025 · Gastroenterology, Urology
Device Facts
Record ID
K250584
Device Name
Rezum System
Applicant
Boston Scientific Corporation
Product Code
KNS · Gastroenterology, Urology
Decision Date
Jun 11, 2025
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 876.4300
Device Class
Class 2
Attributes
Therapeutic
Indications for Use
The Rezüm System is intended to relieve symptoms, obstructions, and reduce prostate tissue associated with benign prostatic hyperplasia(BPH). It is indicated for men ≥ 50 years of age with a prostate volume 30 cm3 ≤ 150 cm3. The Rezüm System is also indicated for treatment of prostate with hyperplasia of the central zone and/or a median lobe.
Device Story
The Rezüm System treats benign prostatic hyperplasia (BPH) via convective water vapor thermal therapy. The system consists of a reusable generator and a sterile, single-use delivery device. The physician injects controlled 9-second doses of water vapor into the prostate transition zone or median lobe. The vapor condenses upon contact with tissue, releasing thermal energy that denatures cell membranes and causes cell death. This process reduces prostate volume and collapses vasculature in the treatment zone, facilitating a bloodless procedure. Denatured tissue is subsequently absorbed by the body or sloughed off and expelled via urination. The procedure is performed to relieve urinary symptoms and obstructions. The device is identical to the predicate; the update expands the indicated prostate volume range to 150 cm³.
Clinical Evidence
Evidence includes a systematic review, meta-analysis, and a manufacturer-sponsored prospective, non-randomized, single-arm study. The study compared safety and effectiveness in patients with prostate volumes >80 cm³ and ≤150 cm³ against the pivotal clinical study data for patients ≤80 cm³. Results showed comparable functional and quality of life improvements, no negative impact on sexual function, and similar adverse event rates between the two groups. No unexpected adverse events were reported.
Technological Characteristics
The system utilizes radiofrequency current to generate water vapor for thermal ablation. Components include a reusable generator and a sterile, single-use delivery device kit (delivery device, syringe, spike adaptor, water vial). The device is an endoscopic electrosurgical unit (21 CFR 876.4300). Technological characteristics are identical to the predicate device.
Indications for Use
Indicated for men ≥ 50 years of age with benign prostatic hyperplasia (BPH) and prostate volume between 30 cm³ and 150 cm³, including hyperplasia of the central zone and/or median lobe.
Regulatory Classification
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.
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FDA U.S. FOOD & DRUG ADMINISTRATION
June 11, 2025
Boston Scientific Corporation
Joseph Tabor
Regulatory Affairs Specialist
100 Boston Scientific Way
Marlborough, Massachusetts 01752
Re: K250584
Trade/Device Name: Rezum System
Regulation Number: 21 CFR 876.4300
Regulation Name: Endoscopic Electrosurgical Unit and accessories
Regulatory Class: II
Product Code: KNS
Dated: February 27, 2025
Received: May 6, 2025
Dear Joseph Tabor:
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.
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).
U.S. Food & Drug Administration
10903 New Hampshire Avenue
Silver Spring, MD 20993
www.fda.gov
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K250584 - Joseph Tabor
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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.
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
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K250584 - Joseph Tabor
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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,
Mark J. Antonino -S
Mark J. Antonino, M.S.
Assistant Director
DHT3B: Division of Reproductive, Gynecology, and Urology Devices
OHT3: Office of Gastrorenal, ObGyn, General Hospital, and Urology Devices
Office of Product Evaluation and Quality
Center for Devices and Radiological Health
Enclosure
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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.
Submission Number (if known)
K250584
Device Name
Rezüm System
Indications for Use (Describe)
The Rezüm System is intended to relieve symptoms, obstructions, and reduce prostate tissue associated with benign prostatic hyperplasia(BPH). It is indicated for men ≥ 50 years of age with a prostate volume 30 cm3 ≤ 150 cm3. The Rezüm 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)
☑ Prescription Use (Part 21 CFR 801 Subpart D)
☐ Over-The-Counter Use (21 CFR 801 Subpart C)
# CONTINUE ON A SEPARATE PAGE IF NEEDED.
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*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:
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K250584
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# 510(k) Summary
## A. Date Prepared
This 510(k) summary was prepared February 27, 2025
## B. Submitter
Boston Scientific Corporation
Urology Division
100 Boston Scientific Way
Marlborough, MA 01752
## C. Contacts
Joseph Tabor
Regulatory Affairs Specialist II
Joseph.Tabor@bsci.com
(508) 382-0313
Alternate:
Cody Johnson
Regulatory Affairs Manager
Cody.Johnson@bsci.com
(952) 930-5736
## D. Subject Device
| Trade Name | Rezūm System |
| --- | --- |
| Common Name | Vapor Ablation Device |
| Regulation Name | Endoscopic electrosurgical unit and accessories |
| Regulation Number | 21 CFR 876.4300 |
| Classification | Class II |
| Product Code | KNS |
## E. Predicate Device
| Trade Name | Rezūm System |
| --- | --- |
| Common Name | Vapor Ablation Device |
| Regulation Name | Endoscopic electrosurgical unit and accessories |
| Regulation Number | 21 CFR 876.4300 |
| Classification | Class II |
| Product Code | KNS |
| 510(k) Submitter/Holder | Boston Scientific Corporation |
| 510(k) #/Clearance Date | K191505/cleared August 2, 2019 |
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K250584
Page 2 of 3
# 510(k) Summary
## F. Device Description
The Rezūm System is designed to treat patients with bothersome urinary symptoms associated with benign prostatic hyperplasia (BPH). The Rezūm System utilizes radiofrequency current to generate "wet" thermal energy in the form of water vapor, which is then injected into the transition zone and/or median lobe of the prostate tissue in controlled 9-second doses. The vapor that is injected into the prostate tissue rapidly disperses through the interstitial space between the tissue cells. As the vapor cools, it condenses immediately on contact with tissue and the stored thermal energy is released, denaturing the cell membranes and causing cell death.
The denatured cells are absorbed by the body, which reduces the volume of prostate tissue adjacent to the urethra. The vapor condensation process also causes a rapid collapse of vasculature in the treatment zone, resulting in a bloodless procedure.
Following thermal therapy for BPH, small pieces of coagulated tissue may slough off and be expelled via urination. This sloughing process may continue for a few months post-procedure depending on the rate of healing.
The Rezūm System consists of the following:
- Rezūm Generator – reusable, non-sterile capital equipment, provided with one power cord
- Rezūm Delivery Device Kit – sterile, single-use kit containing the following disposable components:
- One sterile Delivery Device with cable and tubing
- One sterile syringe
- One sterile spike adaptor
- One sterile water vial
## G. Intended Use/Indications for Use
The Rezūm System is intended to relieve symptoms, obstructions, and reduce prostate tissue associated with benign prostatic hyperplasia (BPH). It is indicated for men ≥ 50 years of age with a prostate volume 30 cm³ ≤ 150 cm³. The Rezūm System is also indicated for treatment of prostate with hyperplasia of the central zone and/or a median lobe.
## H. Technological Characteristics Compared to the Predicate Device
The technological characteristics of the proposed (subject) Rezūm System are identical to those of the predicate device. There are no changes to any device features. The only change is a modification to the Indications for Use to expand the prostate volume upper limit from ≤ 80 cm³ to ≤ 150 cm³. The change in Indications for Use does not create a new intended use. The predicate and the proposed Rezūm System are both intended to relieve symptoms, obstructions, and reduce prostate tissue associated with BPH. The modification to the Indications for Use is supported by manufacturer-sponsored and independent clinical studies and the clinical evidence demonstrates that there are no new safety or effectiveness concerns regarding use of the Rezūm System in patients with prostates >80 cm³ and ≤ 150 cm³.
## I. Substantial Equivalence
The proposed Rezūm System is substantially equivalent to the predicate Rezūm System (K191505). The proposed and predicate Rezūm System are both intended to relieve symptoms, obstructions, and reduce prostate tissue associated with BPH, and the modification to the
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K250584
Page 3 of 3
## 510(k) Summary
Indications for Use does not introduce any new safety or effectiveness concerns. The Rezūm System intended use, principle of operation and technological characteristics remain the same.
## J. Performance Data
The Indications for Use modification to the proposed Rezūm System has been evaluated in comparison to the predicate device. The expanded indication is supported by a systematic review and meta-analysis of clinical studies that examined safety and effectiveness of the Rezūm System in symptomatic BPH patients with prostate volumes >80 cm³ and compared outcomes to patients with prostate volumes ≤80 cm³. In addition, data from a manufacturer-sponsored prospective, non-randomized, single-arm study that evaluated safety and effectiveness of the Rezūm System in patients with prostate volumes >80 cm³ and ≤150 cm³ was compared to data from the Rezūm System pivotal clinical study. The clinical evidence showed overall comparable results between patients with prostate volumes >80 cm³ and ≤80 cm³. Significant and similar improvements in functional and quality of life outcomes were demonstrated in both patient populations, with no negative impact to sexual function. Patients with prostate volumes >80 cm³ had generally similar rates of adverse events, including serious complications. No unexpected adverse events were reported, and all adverse events were consistent with those reported in the Rezūm System pivotal clinical study. Use of the proposed device in the expanded patient population does not result in any new concerns of safety or effectiveness.
## K. Conclusion
Based on the intended use, technological characteristics, and the clinical evidence presented in this submission to support use of the device in the expanded patient population, the Rezūm System is substantially equivalent to the predicate device.
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