BREAKING  Presidio Medical wins FDA IDE approval for global pivotal FULFILL study (2025) $72M Series C led by Deerfield Management Ultra Low Frequency neuromodulation reversibly blocks pain signals Early human data: ~90% pain improvement over two weeks Targeting a ~$20B unmet need in chronic low back pain Research published in Science Translational Medicine BREAKING  Presidio Medical wins FDA IDE approval for global pivotal FULFILL study (2025) $72M Series C led by Deerfield Management Ultra Low Frequency neuromodulation reversibly blocks pain signals Early human data: ~90% pain improvement over two weeks Targeting a ~$20B unmet need in chronic low back pain Research published in Science Translational Medicine
San Mateo, California · Clinical-Stage Medtech · Est. 2017

Presidio Medical

Rewiring the physics of pain relief - one ultra low frequency waveform at a time.

2017Founded
$102MTotal Raised
~42Employees
US + AUSFULFILL Trial
Presidio Medical branding and Ultra Low Frequency neuromodulation identity
Presidio Medical, San Mateo, California. The company's Ultra Low Frequency platform aims to quiet pain at the nerve rather than mask it. - Photo: company materials

The Company Turning Down the Volume on Pain

In a San Mateo lab, a small team of engineers, electrochemists and neuroscientists has spent years chasing a deceptively simple idea: what if chronic pain could be switched off at the nerve, and switched back on again?

Presidio Medical is a clinical-stage medical device company developing an Ultra Low Frequency (ULF) neuromodulation platform - a spinal cord stimulation (SCS) system designed to treat "diseases of undesired neural activity." Its first target is chronic nociceptive low back pain, one of medicine's most stubborn and underserved conditions.

Conventional spinal cord stimulators mask pain by replacing it with a tingling sensation, or paresthesia. Presidio's approach is different in kind, not degree. By delivering very low frequency biphasic electrical currents through leads implanted in the epidural space, the ULF system aims to reversibly block the conduction of pain signals along nerves - achieving a direct-current-like blocking effect without the tissue damage that true direct current would cause.

The word that keeps recurring in Presidio's story is "reversible." In early testing, when the current was turned off, nerve signaling returned. For a field haunted by permanent side effects, that off-switch is not a footnote. It is the point.

Founded in 2017 and led since 2021 by Chairman and CEO Michael Onuscheck, Presidio has raised roughly $102 million to date, including a $72 million Series C led by Deerfield Management. In 2025 it cleared a pivotal regulatory hurdle: FDA approval of its Investigational Device Exemption (IDE), opening the door to its global pivotal trial.

How Ultra Low Frequency Works

01 / SIGNAL

Ultra Low Frequency

A very low frequency biphasic current is generated - designed to mimic the nerve-blocking effect of direct current.

02 / DELIVERY

Epidural Leads

Leads implanted in the epidural space deliver the waveform to the spinal cord (SCS), targeting the pain pathway.

03 / BLOCK

Reversible Inhibition

The current suppresses aberrant nerve firing and blocks conduction of pain signals - without damaging tissue.

04 / RELIEF

Localized Pain Relief

Neuronal responses tied to chronic low back pain are reduced. Turn it off, and signaling returns.

The counterintuitive physics

Direct current can block nerve conduction - but it damages tissue. Very high frequencies stimulate. Presidio's insight sits at the far low end of the spectrum: ultra low frequency currents that borrow direct current's blocking power while staying tissue-safe and reversible.

ULF waveform (illustrative)

The Problem It Solves

An unmet need

Chronic nociceptive low back pain is widespread and hard to treat. There is currently no FDA-approved spinal cord stimulation therapy specifically for it - a genuine gap in care.

The patients left behind

Presidio focuses on people who have exhausted conventional options - the patients other therapies gave up on. Ultimately, its customers are those patients and the pain physicians and neurosurgeons who treat them.

A large market

The chronic nociceptive low back pain opportunity is estimated at roughly $20 billion - a market defined, tellingly, by the words "no approved option."

"Transforming the way neuromodulation balances the human nervous system, and striving to end the cycle of unnecessary pain and help patients live their best lives."- Presidio Medical mission

How It's Different

Block, don't mask

Legacy SCS replaces pain with paresthesia. ULF aims to reversibly block the pain signal itself - a fundamentally different mechanism.

Reversible by design

Switch the current off and nerve signaling returns. Early human data showed pain returning after the lead was explanted - proof the effect is real.

Whitespace, not a fast-follow

Rather than iterating on an existing category, Presidio targets an indication - nociceptive low back pain - with no approved SCS competitor.

Five disciplines, one implant

Circuit design, computational modeling, material science, electrochemistry and neuroscience converge in a single device.

Established neuromodulation players include Medtronic, Boston Scientific, Abbott and Nevro - none with an approved SCS therapy for nociceptive low back pain.

Products & Programs

Platform · Investigational

ULF Neuromodulation System

A spinal cord stimulation platform delivering Ultra Low Frequency biphasic currents via epidural leads to reversibly block pain signals without damaging tissue. First indication: chronic nociceptive low back pain. Still investigational and not yet approved for commercial use.

Clinical · 2025

The FULFILL Study

A global, pivotal, randomized controlled trial across the United States and Australia evaluating the safety and efficacy of the ULF platform for chronic nociceptive low back pain - enabled by FDA IDE approval in 2025.

Business Model & Expertise

How it makes its way

As a clinical-stage medtech company, Presidio is pre-commercial. It builds value through intellectual property, clinical evidence and regulatory milestones, funded by venture and strategic investors, advancing its ULF implant through FDA-regulated trials toward eventual commercialization and reimbursement.

Where the edge lives

Presidio's moat is scientific: a proprietary waveform, peer-reviewed research, and deep cross-disciplinary engineering. Its 2021 publication in Science Translational Medicine turned a pitch into evidence.

Funding & Backers

Series C (2023)$72M
Total raised to date~$102M

The June 2023 Series C was led by Deerfield Management, with existing investors Invus Opportunities and Action Potential Venture Capital, joined by ShangBay Capital. Proceeds fund team expansion, manufacturing scale-up and pivotal clinical studies.

Selected investors

• Deerfield Management (lead)
• Invus Opportunities
• Action Potential Venture Capital
• ShangBay Capital

Timeline

2017

Presidio Medical founded

Launched in the San Francisco Bay Area to build neuromodulation devices based on ultra low frequency signals.

2021

Peer-reviewed science

Research showing ULF currents reversibly block axonal conduction and chronic pain is published in Science Translational Medicine.

2021

Onuscheck becomes CEO

After two years on the board, Michael Onuscheck steps in as Chairman and CEO in September.

2023

$72M Series C

Deerfield Management leads a $72 million round to scale manufacturing and fund pivotal trials.

2024

Board expands

Richard J. Buchholz joins the Board of Directors.

2025

FDA IDE & new CFO

IDE approval clears the way for the global FULFILL study; Dimas Jimenez is appointed CFO.

People

Michael Onuscheck

CHAIRMAN & CEO
Veteran medtech executive who joined the board in 2019 and took the top role in 2021.

Kenneth Wu

CO-FOUNDER
Co-founded the company in 2017 to pursue ultra low frequency neuromodulation.

Michael Ackermann

CO-FOUNDER & BOARD
Co-founder and board member helping steer the company's scientific direction.

Frequently Asked

What does Presidio Medical do?

It is a clinical-stage medical device company developing an Ultra Low Frequency (ULF) neuromodulation platform - a spinal cord stimulation system that reversibly blocks pain signals along nerves, starting with chronic nociceptive low back pain.

How is ULF different from other spinal cord stimulation?

Instead of masking pain with a tingling sensation, ULF uses very low frequency biphasic currents to reversibly block nerve conduction - similar to the effect of direct current, but without damaging tissue.

Is the ULF system FDA approved?

Not yet. It is investigational. In 2025 Presidio received FDA IDE approval to run its pivotal FULFILL trial; commercial approval would depend on trial outcomes.

How much funding has Presidio raised?

The company raised a $72 million Series C led by Deerfield Management in 2023, with total funding across rounds reported at roughly $102 million.

Who leads Presidio Medical?

Michael Onuscheck is Chairman and CEO. The company was co-founded by Kenneth Wu and Michael Ackermann, and is headquartered in San Mateo, California.