Motor Cortex Stimulation for Chronic Neuropathic Pain

A Clinical Evaluation for the Management of Patients With Chronic Neuropathic Pain With Cortical Stimulation

The purpose of this study is to evaluate the efficacy of cortical stimulation (CS) as an adjunctive treatment for chronic neuropathic pain.

Study Overview

• Status: Unknown
• Conditions: Neuropathic Pain; Facial Pain; Post-stroke Pain; Brachial Plexus Avulsion; Phantom Limb Pain of the Upper Extremities
• Intervention / Treatment: Device: Motor Cortex Stimulation using SJM EonC Stimulator

Detailed Description

Prospective, controlled, double blind, randomized, crossover study with endpoint evaluations at the end of each 3-month treatment period.

An interim analysis will be conducted by a blinded committee when approximately half of the patients have finished the study.

• Study Type: Interventional
• Enrollment (Actual): 38
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Brazil
  • São Paulo, Brazil
    • University of Sao Paulo - Hospital das Clinicas

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Men and women (non-pregnant) age 21-70 years;
• Able to give informed consent in accordance with institutional policies;
• Diagnosis of chronic neuropathic pain according to the DN4 Neuropathic Pain Diagnosis scale (score ≥ 4).
• Documented pain for at least 12 months;
• Documented previous or current treatment for neuropathic pain with medications from at least two of the following groups at adequate doses: antidepressants, anticonvulsants, and/or gabapentinoids;
• VAS scores of at least 6 during baselines #1 and 2.
• Documented clinical diagnosis of neuropathic pain associated with one of the following conditions: facial pain, post-stroke pain, brachial plexus avulsion, or phantom limb pain of the upper extremities.
• In the group with post-stroke pain, only patients with predominant face and upper extremity pain will be included. This will be defined as a difference of ≥ 30% or ≥ 2 points in VAS scores between these regions and lower extremity (in patients who also have pain in the leg).
• No change in current neuropathic pain medication regimen for at least 4 weeks prior to study enrollment.
• Able to comply with all testing and follow-up requirements as defined by the study protocol.
• Must be determined medically stable by surgeon to undergo cortical stimulation surgical procedure.

Exclusion Criteria:

• Alcohol, medication, or illegal substance dependence or abuse within last 12 months;
• Trigeminal neuralgia or atypical facial pain.
• Post-stroke pain predominantly in the lower extremity.
• Advanced cardiovascular disease which renders anesthesia and surgery as unsafe as determined by neurosurgeon;
• Clinically relevant abnormality (e.g. tumor) on study MRI;
• Has cardiac pacemaker/defibrillator or other implanted active stimulator;
• Has a medical condition requiring a repetitive MRI body scan;
• Requires chemotherapy for the treatment of malignancy or requiring chronic oral or intravenous, immunosuppressive, or steroid therapy;
• Is unable to comply with study visit schedule and timeline;
• Past ablative or relevant intracranial surgery;
• A female lactating or of child bearing potential, with a positive pregnancy test or not using adequate contraception;
• Other medical conditions likely to require hospitalization within the next year.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Sham Comparator: Sham stimulation	Device: Motor Cortex Stimulation using SJM EonC Stimulator; Patients will be randomized to receive either active stimulation the first 3 months followed by a one-month washout, followed by Sham Stimulation the next 3 months, vs. the reverse order of treatment, followed by single blind stimulation, and an open label phase.
Active Comparator: Active stimulation	Device: Motor Cortex Stimulation using SJM EonC Stimulator; Patients will be randomized to receive either active stimulation the first 3 months followed by a one-month washout, followed by Sham Stimulation the next 3 months, vs. the reverse order of treatment, followed by single blind stimulation, and an open label phase.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Visual Analog Scale (VAS)	The primary analysis of effectiveness is based on the mean differences in changes from the period-specific baseline in VAS scores when patients are receiving 3 month of active vs. 3 months of sham stimulation on a double-blinded fashion.	Approximately 7 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Visual Analog Scale, responder	defined as a ≥30% or 2 points reduction from baseline in VAS scores	Participants will be followed for approximatley 18 months
Neuropathic Pain Symptom Inventory (NPSI)		Participants will be followed for approximatley 18 months
Brief Pain Inventory (BPI)		Participants will be followed for approximatley 18 months
Short Form of the McGill Pain Questionnaire(SF-MPQ)		Participants will be followed for approximatley 18 months
Sickness Impact Profile (SIP)		Participants will be followed for approximatley 18 months
Medication Quantification Scale (MQS)		Participants will be followed for approximatley 18 months
SF-36 Health Survey and safety		Participants will be followed for approximatley 18 months
Pain Catastrophizing Scale (PCS)		Participants will be followed for approximatley 18 months
Global Impression of Change (patient and evaluator's version)		Participants will be followed for approximatley 18 months
Device related Adverse Events		Participants will be followed for approximatley 18 months

Collaborators and Investigators

• Sponsor: Abbott Medical Devices
• Investigators: Study Director: Edward Karst, Abbott Neuromodulation

Study record dates

Study Major Dates

• Study Start: October 1, 2012
• Primary Completion (Anticipated): December 31, 2020
• Study Completion (Anticipated): December 31, 2020

Study Registration Dates

• First Submitted: January 13, 2012
• First Submitted That Met QC Criteria: March 12, 2012
• First Posted (Estimate): March 14, 2012

Study Record Updates

• Last Update Posted (Actual): June 12, 2020
• Last Update Submitted That Met QC Criteria: June 11, 2020
• Last Verified: June 1, 2020

More Information

Terms related to this study

• Keywords: Neuropathic pain; Motor Cortex Stimulation
• Additional Relevant MeSH Terms: Pathologic Processes; Nervous System Diseases; Postoperative Complications; Pain; Neurologic Manifestations; Neurobehavioral Manifestations; Neuromuscular Diseases; Peripheral Nervous System Diseases; Perceptual Disorders; Pain, Postoperative; Neuralgia; Facial Pain; Phantom Limb
• Other Study ID Numbers: C-11-13