Neurolyser XR (NXR100)

DEN250015 · Fusmobile, Inc. · SGN · Nov 14, 2025 · Neurology

Device Facts

• Record ID: DEN250015
• Device Name: Neurolyser XR (NXR100)
• Applicant: Fusmobile, Inc.
• Product Code: SGN · Neurology
• Decision Date: Nov 14, 2025
• Decision: DENG
• Submission Type: Direct
• Regulation: 21 CFR 882.4420
• Device Class: Class 2
• Attributes: Therapeutic

Indications for Use

The Neurolyser XR is indicated for the thermal ablation (neurolysis) of the medial branch nerve of the lumbar facet joint(s) (L1 to L5) for the treatment of chronic, facet-mediated low back pain of at least 6 months duration and a confirmed diagnosis based on positive response to lumbar branch block or denervation.

Device Story

Neurolyser XR is a high intensity focused ultrasound (HIFU) system designed for peripheral neural tissue ablation. Device transmits ultrasound energy to produce thermal lesions in targeted lumbar medial branch nerves. System utilizes acoustic coupling to focus energy into a defined volume. Intended for use in clinical settings by healthcare professionals. Output consists of thermal energy delivery for neurolysis. Clinical benefit includes treatment of chronic, facet-mediated low back pain. Safety is managed through precise targeting, acoustic power control, and monitoring of focal temperature to prevent unintended tissue injury or cavitation.

Clinical Evidence

No clinical trial data provided in the document. Evidence requirements for this De Novo classification include in vivo performance testing to demonstrate intended ablative energy delivery and evaluation of adverse effects, alongside non-clinical performance testing (acoustic mapping, power output, focal temperature, targeting accuracy, and cavitation safety).

Technological Characteristics

High intensity focused ultrasound (HIFU) system. Employs acoustic coupling to deliver thermal energy. Technical parameters include acoustic pressure mapping, focal region characterization, and acoustic power output control. Patient-contacting components must be biocompatible. Requires software verification and validation. Electrical safety and electromagnetic compatibility (EMC) testing required.

Indications for Use

Indicated for patients with chronic, facet-mediated low back pain (duration ≥ 6 months) confirmed by positive response to lumbar branch block or denervation, requiring thermal ablation of the medial branch nerve of the lumbar facet joint(s) (L1 to L5).

Regulatory Classification

Identification

The Neurolyser XR is a high intensity focused ultrasound system for peripheral neural tissue ablation. It is a device that transmits ultrasound energy to produce thermal lesions in a defined, targeted volume of peripheral nervous tissue through acoustic coupling. It is indicated for the thermal ablation (neurolysis) of the medial branch nerve of the lumbar facet joint(s) (L1 to L5) for the treatment of chronic, facet-mediated low back pain of at least 6 months duration and a confirmed diagnosis based on positive response to lumbar branch block or denervation.

Special Controls

In combination with the general controls of the FD&C Act, the high intensity focused ultrasound system for peripheral neural tissue ablation is subject to the following special controls: (1) In vivo performance testing must demonstrate that the device performs as intended to deliver ablative energy and evaluate all adverse effects, including adverse tissue injury to target and non-target tissues. (2) Non-clinical performance testing must demonstrate that the device performs as intended under anticipated conditions of use, including: (i) Characterization of acoustic pressure, including an acoustic map of relevant sections of the focal region, near-, and far-fields; (ii) Characterization of overall acoustic power output and reproducibility; (iii) Characterization of ultrasound induced focal temperature; (iv) Demonstration of device positioning and targeting accuracy; and (v) Assessment of ultrasound induced cavitation safety. (3) Performance data must demonstrate the electrical safety and electromagnetic compatibility of the device. (4) Software verification, validation, and hazard analysis must be performed. (5) The patient-contacting components of the device must be demonstrated to be biocompatible. (6) Labeling must include: (i) Detailed description of the device components and technical parameters including targeting accuracy; and (ii) A shelf life for single use components.

Submission Summary (Full Text)

{0}

FDA U.S. FOOD & DRUG ADMINISTRATION

November 14, 2025

FUSMobile, Inc.
Ron Aginsky
President and Director
6120 Windward Parkway
Suite 210
Alpharetta, Georgia 30005

Re: DEN250015
Trade/Device Name: Neurolyser XR
Regulation Number: 21 CFR 882.4420
Regulation Name: High intensity focused ultrasound system for peripheral neural tissue ablation
Regulatory Class: Class II
Product Code: SGN
Dated: April 24, 2025
Received: April 25, 2025

Dear Ron Aginsky:

The Center for Devices and Radiological Health (CDRH) of the Food and Drug Administration (FDA) has completed its review of your De Novo request for classification of the Neurolyser XR, a prescription device under 21 CFR Part 801.109 with the following indications for use:

The Neurolyser XR is indicated for the thermal ablation (neurolysis) of the medial branch nerve of the lumbar facet joint(s) (L1 to L5) for the treatment of chronic, facet-mediated low back pain of at least 6 months duration and a confirmed diagnosis based on positive response to lumbar branch block or denervation.

FDA concludes that this device should be classified into Class II. This order, therefore, classifies the Neurolyser XR, and substantially equivalent devices of this generic type, into Class II under the generic name high intensity focused ultrasound system for peripheral neural tissue ablation.

FDA identifies this generic type of device as:

High intensity focused ultrasound system for peripheral neural tissue ablation. A high intensity focused ultrasound system for peripheral neural tissue ablation is a device that transmits ultrasound energy to produce thermal lesions in a defined, targeted volume of peripheral nervous tissue through acoustic coupling.

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

{1}

DEN250015 - Ron Aginsky
Page 2

Section 513(f)(2) of the Food, Drug and Cosmetic Act (the FD&C Act) was amended by section 607 of the Food and Drug Administration Safety and Innovation Act (FDASIA) on July 9, 2012. This law provides two options for De Novo classification. First, any person who receives a "not substantially equivalent" (NSE) determination in response to a 510(k) for a device that has not been previously classified under the Act may request FDA to make a risk-based classification of the device under section 513(a)(1) of the Act. On December 13, 2016, the 21st Century Cures Act removed a requirement that a De Novo request be submitted within 30 days of receiving an NSE determination. Alternatively, any person who determines that there is no legally marketed device upon which to base a determination of substantial equivalence may request FDA to make a risk-based classification of the device under section 513(a)(1) of the Act without first submitting a 510(k). FDA shall, within 120 days of receiving such a request, classify the device. This classification shall be the initial classification of the device. Within 30 days after the issuance of an order classifying the device, FDA must publish a notice in the Federal Register announcing the classification.

On April 25, 2025, FDA received your De Novo requesting classification of the Neurolyser XR. The request was submitted under section 513(f)(2) of the FD&C Act. In order to classify the Neurolyser XR into class I or II, it is necessary that the proposed class have sufficient regulatory controls to provide reasonable assurance of the safety and effectiveness of the device for its intended use. After review of the information submitted in the De Novo, FDA has determined that, for the previously stated indications for use, the Neurolyser XR can be classified in class II with the establishment of special controls for class II. FDA believes that class II (special) controls provide reasonable assurance of the safety and effectiveness of the device type. The identified risks and mitigation measures associated with the device type are summarized in the following table:

| Risks to Health | Mitigation Measures |
| --- | --- |
| Tissue injury resulting from:
• Unintended tissue heating
• Cavitation
• Mistargeting or higher or lower energy than intended
• Electrical shock
• Acute radiation injury
• User error | In vivo performance testing
Non-clinical performance testing
Software verification, validation, and hazard analysis
Electrical safety testing
Electromagnetic compatibility testing
Labeling |
| Pain and nervous system disorders:
• Skin discomfort or burns
• Paresthesia
• Ineffective treatment leading to worsening back pain | In vivo performance testing |
| Adverse tissue reaction | Biocompatibility evaluation |

In combination with the general controls of the FD&C Act, the high intensity focused ultrasound system for peripheral neural tissue ablation is subject to the following special controls:

(1) In vivo performance testing must demonstrate that the device performs as intended to deliver ablative energy and evaluate all adverse effects, including adverse tissue injury to target and non-target tissues.
(2) Non-clinical performance testing must demonstrate that the device performs as intended under anticipated conditions of use, including:

{2}

DEN250015 - Ron Aginsky
Page 3

(i) Characterization of acoustic pressure, including an acoustic map of relevant sections of the focal region, near-, and far-fields;
(ii) Characterization of overall acoustic power output and reproducibility;
(iii) Characterization of ultrasound induced focal temperature;
(iv) Demonstration of device positioning and targeting accuracy; and
(v) Assessment of ultrasound induced cavitation safety.

(3) Performance data must demonstrate the electrical safety and electromagnetic compatibility of the device.
(4) Software verification, validation, and hazard analysis must be performed.
(5) The patient-contacting components of the device must be demonstrated to be biocompatible.
(6) Labeling must include:
(i) Detailed description of the device components and technical parameters including targeting accuracy; and
(ii) A shelf life for single use components.

In addition, this is a prescription device and must comply with 21 CFR 801.109.

Although this letter refers to your product as a device, please be aware that some granted products may instead be combination products. If you have questions on whether your product is a combination product, contact [e-mail].

Section 510(m) of the FD&C Act provides that FDA may exempt a class II device from the premarket notification requirements under section 510(k) of the FD&C Act, if FDA determines that premarket notification is not necessary to provide reasonable assurance of the safety and effectiveness of the device type. FDA has determined premarket notification is necessary to provide reasonable assurance of the safety and effectiveness of the device type and, therefore, the device is not exempt from the premarket notification requirements of the FD&C Act. Thus, persons who intend to market this device type must submit a premarket notification containing information on the high intensity focused ultrasound system for peripheral neural tissue ablation they intend to market prior to marketing the device.

Please be advised that FDA's decision to grant this De Novo request does not mean that FDA has made a determination that your device complies with other requirements of the FD&C Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the FD&C 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) for 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-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 4, Subpart A) for combination products; and if applicable, the electronic product radiation control provisions (Sections 531-542 of the FD&C Act; 21 CFR 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

{3}

DEN250015 - Ron Aginsky
Page 4

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.

A notice announcing this classification order will be published in the Federal Register. A copy of this order and supporting documentation are on file in the Dockets Management Branch (HFA-305), Food and Drug Administration, 5630 Fishers Lane, Room 1061, Rockville, MD 20852 and are available for inspection between 9 a.m. and 4 p.m., Monday through Friday.

As a result of this order, you may immediately market your device as described in the De Novo request, subject to the general control provisions of the FD&C Act and the special controls identified in this order.

For comprehensive regulatory information about medical devices and radiation-emitting products, 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 ([e-mail]) or phone [phone] or 301-796-7100).

If you have any questions concerning the contents of the letter, please contact Morgan Dundon, Ph.D at [e-mail].

Sincerely,

Jaime Raben -S

Jaime Raben, Ph.D.
Director

DHT5A: Division of Neurosurgical, Neurointerventional, and Neurodiagnostic Devices
OHT5: Office of Neurological and Physical Medicine Devices
Office of Product Evaluation and Quality
Center for Devices and Radiological Health