Trial Outcomes & Findings for Closed-loop Deep Brain Stimulation to Treat Refractory Neuropathic Pain (NCT NCT03029884)

Results Overview

Visual Analog Score is indicated by the patient by marking a 10 cm line as they rate their pain intensity from 0 to 100 in mm. Higher scores represent worse outcome.

Recruitment status

ACTIVE_NOT_RECRUITING

Study phase

NA

Target enrollment

4 participants

Primary outcome timeframe

2 years

Results posted on

2026-02-12

Participant Flow

Recruitment was done through the UCSF Pain management clinic and online from clinicaltrials.gov from October 2017 to December 2019

There was a 6 month run-in period for collection of personalized neural signals before stimulation began

Participant milestones

Participant milestones
Measure	Open vs Closed Loop vs Sham DBS Chronic brain recording and stimulation with unilateral or bilateral implantation in pain-related brain regions. Both thalamic pain syndrome and phantom pain participants will participate in active DBS, blinded to the participant. Open-loop DBS refers to tonic stimulation of ACC or OFC regions without feedback control. Closed loop is feedback enabled stimulation triggered by pain biomarkers. Sham is no stimulation. Because \>6 sequences were used, only 1 arm/group is defined as per instructions.
Inactive DBS Run in Period (6 Months) STARTED	4
Inactive DBS Run in Period (6 Months) COMPLETED	4
Inactive DBS Run in Period (6 Months) NOT COMPLETED	0
Open-Loop DBS (6 Weeks) STARTED	4
Open-Loop DBS (6 Weeks) COMPLETED	4
Open-Loop DBS (6 Weeks) NOT COMPLETED	0
Closed-Loop DBS (6 Weeks) STARTED	4
Closed-Loop DBS (6 Weeks) COMPLETED	4
Closed-Loop DBS (6 Weeks) NOT COMPLETED	0
Sham DBS (3 Weeks) STARTED	4
Sham DBS (3 Weeks) COMPLETED	4
Sham DBS (3 Weeks) NOT COMPLETED	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Closed-loop Deep Brain Stimulation to Treat Refractory Neuropathic Pain

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	All Study Participants n=4 Participants Chronic brain recording and stimulation with unilateral or bilateral implantation in pain-related brain regions. Both thalamic pain syndrome and phantom pain participants will participate in active DBS, blinded to the participant. Medtronic Activa PC+S: In Aim 2 we will perform closed loop DBS versus sham (randomized) to evaluate efficacy of stimulation for analgesia. In Aim 3, closed-loop DBS will be compared to open-loop DBS in a patient blinded, randomized fashion.
Age, Categorical <=18 years	0 Participants n=47 Participants
Age, Categorical Between 18 and 65 years	4 Participants n=47 Participants
Age, Categorical >=65 years	0 Participants n=47 Participants
Age, Continuous	59 years n=47 Participants
Sex: Female, Male Female	2 Participants n=47 Participants
Sex: Female, Male Male	2 Participants n=47 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants n=47 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	4 Participants n=47 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=47 Participants
Region of Enrollment United States	4 participants n=47 Participants
Pain Intensity Numerical Rating Score	7.95 units on a scale n=47 Participants

PRIMARY outcome

Timeframe: 2 years

Visual Analog Score is indicated by the patient by marking a 10 cm line as they rate their pain intensity from 0 to 100 in mm. Higher scores represent worse outcome.

Outcome measures

Outcome measures
Measure	Inactive DBS Run in Period n=4 Participants This period includes the DBS implant surgery, and a run in period of up to 6 months when brain signals are recorded, but electrical stimulation is not yet turned on.	Open Loop DBS n=4 Participants Chronic brain recording and stimulation with unilateral or bilateral implantation in pain-related brain regions. Both thalamic pain syndrome and phantom pain participants will participate in active DBS, blinded to the participant. Open-loop DBS refers to tonic stimulation of ACC or OFC regions without feedback control. Because \>6 sequences were used, only 1 arm/group is defined as per instructions.	Closed Loop DBS n=4 Participants Closed loop is feedback enabled stimulation triggered by pain biomarkers.	Sham n=4 Participants Sham is no stimulation.
Visual Analog Score	76 units on a scale (millimeters) Interval 50.0 to 100.0	74 units on a scale (millimeters) Interval 22.0 to 100.0	75 units on a scale (millimeters) Interval 50.0 to 100.0	75 units on a scale (millimeters) Interval 61.0 to 100.0

SECONDARY outcome

Timeframe: 4 years

The Neuropathic pain Questionnaire (NPQ) is an assessment instrument for neuropathic pain intensity and quality. It contains 12 items: 10 related to sensations or sensory responses and two related to affect. The items are totaled and rated out of 12, with 12 being in the most neuropathic pain.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: 4 years

The Becks Depression Inventory is commonly used assessment tools to quantify and track depression mood state over time. Its a single value outcome measurement ranging from 0 to 63, with 63 being the most depressed.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: 4 years

The Becks Anxiety Inventory is commonly used assessment tools to quantify and track anxious mood state over time.Its a single value outcome measurement ranging from 0 to 63, with 63 the most anxious.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: 4 years

The NIH PROMIS toolbox contains a host of survey questions tailored to measurement of specific disease states such as pain, global health and function. The patient impression evaluates patient self-evaluation and physician evaluation of the patient's general health ranging form 0 to 7 with 7 being the worst general health.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: 4 years

We will calculate total number of of breakthrough pain medication pills (eg. opioids, NSAIDs and neuropathic pain medication) used each month, to evaluate if analgesia from DBS reduces average usage.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: 4 years

Each patient will be given a fitbit activity monitor which can record steps taken, flights of stairs climbed, heart rate and sleep quality. These measures will be used to infer functional improvement over time. Heartrate will be tracked as beats per minute (bpm) and the association of bpm with changes in NRS pain will be used to correlate changes in heartrate with pain levels.

Outcome measures

Outcome data not reported

Adverse Events

Inactive DBS Run in Period

Serious events: 1 serious events

Other events: 4 other events

Deaths: 0 deaths

Open Loop DBS

Serious events: 1 serious events

Other events: 4 other events

Deaths: 0 deaths

Closed Loop DBS

Serious events: 0 serious events

Other events: 1 other events

Deaths: 0 deaths

Sham

Serious events: 0 serious events

Other events: 1 other events

Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure	Inactive DBS Run in Period n=4 participants at risk This period includes the DBS implant surgery, and a run in period of up to 6 months when brain signals are recorded, but electrical stimulation is not yet turned on.	Open Loop DBS n=4 participants at risk Chronic brain recording and stimulation with unilateral or bilateral implantation in pain-related brain regions. Both thalamic pain syndrome and phantom pain participants will participate in active DBS, blinded to the participant. Open-loop DBS refers to tonic stimulation of ACC or OFC regions without feedback control. Because \>6 sequences were used, only 1 arm/group is defined as per instructions.	Closed Loop DBS n=4 participants at risk Closed loop is feedback enabled stimulation triggered by pain biomarkers.	Sham n=4 participants at risk Sham is no stimulation.
Nervous system disorders Hemorrhage	25.0% 1/4 • Number of events 1 • 2 years	0.00% 0/4 • 2 years	0.00% 0/4 • 2 years	0.00% 0/4 • 2 years
Psychiatric disorders Suicidal Ideation (passive)	0.00% 0/4 • 2 years	25.0% 1/4 • Number of events 1 • 2 years	0.00% 0/4 • 2 years	0.00% 0/4 • 2 years

Other adverse events

Other adverse events
Measure	Inactive DBS Run in Period n=4 participants at risk This period includes the DBS implant surgery, and a run in period of up to 6 months when brain signals are recorded, but electrical stimulation is not yet turned on.	Open Loop DBS n=4 participants at risk Chronic brain recording and stimulation with unilateral or bilateral implantation in pain-related brain regions. Both thalamic pain syndrome and phantom pain participants will participate in active DBS, blinded to the participant. Open-loop DBS refers to tonic stimulation of ACC or OFC regions without feedback control. Because \>6 sequences were used, only 1 arm/group is defined as per instructions.	Closed Loop DBS n=4 participants at risk Closed loop is feedback enabled stimulation triggered by pain biomarkers.	Sham n=4 participants at risk Sham is no stimulation.
Nervous system disorders Headache	100.0% 4/4 • Number of events 4 • 2 years	100.0% 4/4 • Number of events 7 • 2 years	0.00% 0/4 • 2 years	0.00% 0/4 • 2 years
Nervous system disorders Dizziness	50.0% 2/4 • Number of events 2 • 2 years	0.00% 0/4 • 2 years	25.0% 1/4 • Number of events 1 • 2 years	0.00% 0/4 • 2 years
Nervous system disorders Fall	25.0% 1/4 • Number of events 1 • 2 years	25.0% 1/4 • Number of events 3 • 2 years	0.00% 0/4 • 2 years	25.0% 1/4 • Number of events 1 • 2 years

Additional Information

Prasad Shirvalkar MD, PhD - Principal Investigator

University of California, San Francisco

Phone: 415-885-7246

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place