Chronic Pain
Conditions
Keywords
Chronic pain, peripheral nerve, neuralgia, somatosensory nervous system
Brief summary
The purpose of this study is to investigate whether the StimRouter (SR) electrical stimulation therapy leads to clinically important pain relief in patients with chronic intractable pain of peripheral nerve origin after three months of treatment. At the same time, this study will gather information on side effects associated with the StimRouter electrical stimulation therapy.
Detailed description
Ninety (minimum) up to one hundred twenty-six (126) adult (≥ 22 years) subjects who have severe intractable chronic pain of peripheral nerve origin associated with post traumatic/post surgical neuralgia persisting for 3 months or longer and an average chronic pain level of at least 5 on a 0-10 numeric rating scale, where such pain is attributable to a lesion or disease of the somatosensory nervous system, will be recruited from U.S. outpatient physical medicine and rehabilitation clinics. After screening, subjects who were confirmed to be eligible for the study and provided informed consent will have a pain level assessment period for approximately one week then come back for the Baseline/Implantation visit. Subjects will be trained on and required to complete a patient diary of pain intensity level for at least 7 consecutive days prior to baseline. The randomization and programming will take place approximately two weeks after implantation. Subjects in the treatment group will receive electrical stimulation and pain medication. In contrast, subjects in the parallel control group will receive control stimulation and pain medication. The plan is to have the parallel portion of the study run for approximately 12 weeks (or 3 months) after randomization for efficacy analysis. Subjects in the control group will be allowed to cross over to the treatment group for nine months of electrical stimulation; the subjects in the treatment group will have nine additional months of stimulation treatment such that safety data will be collected throughout a full twelve month period on all available subjects. While the end of the study is approximately 12 months after randomization, as previously stated, the efficacy analyses will be based on the data collected at the end of the 3-month follow-up evaluation.
Interventions
DEVICEStimRouter - active stimulation
The stimulation program settings for this arm are as follows: Stim Settings * Waveform: Symmetric or Asymmetric * Phase Duration: 100-250 µsec * Pulse Rate: 50-100 Hz * Intensity: 0-30mA Time Settings * Constant Stim: On * Total Time: 6 hour
DEVICEStimRouter - Control
The stimulation program settings for this arm are as follows: Stim Settings * Waveform: Symmetric or Asymmetric * Phase Duration: 200 µsec * Pulse Rate: 1 Hz * Intensity: 0 mA Time Settings * Constant Stim: On * Total Time: 6 hour
Sponsors
Bioness Inc
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
22 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. Adults (≥ 22 years) suitable for an implanted electrode for pain relief. 2. Subjects who are able to give informed consent and to understand and comply with study requirements. 3. Subjects who have severe intractable chronic pain of peripheral nerve origin associated with post traumatic/post surgical neuralgia for ≥ 3 months (i.e., intractable to pain medication). 4. Subjects who are able to tolerate skin surface stimulation (TENS). 5. Subjects who have a worst chronic pain level in the last 24 hours ≥ 5/10 (on 0-10 NRS) where such pain is attributable to a lesion or disease of the somatosensory nervous system. 6. Subjects who are on a stable dose of pain medications for at least four weeks prior to screening and willing and able to maintain an equivalent dosage of their current pain medications from randomization to 3-month follow-up.
Exclusion criteria
1. Subjects who are not willing and able to maintain stable dosages of their pain medications from randomization to 3-month follow-up. 2. Subjects with a pain condition that could be confused with their peripheral neuropathic pain or that is more severe than their peripheral neuropathic pain. 3. Subjects who, for implantation in the trunk, have an implanted demand-type cardiac pacemaker or defibrillator. 4. Subjects who have a metal implant in the area for StimRouter implantation without Sponsor approval. Maintain a minimum separation distance of 6 inches (15 cm) between the StimRouter system and all other active implanted devices and metallic implants. 5. Subjects who require, or are likely to require, diathermy at the implant site. 6. Subjects who require, or are likely to require, therapeutic ultrasound at the implant site. 7. Subjects who have a cancerous lesion present near the target stimulation point or near to where the StimRouter user patch will adhere. 8. Subjects who are known or suspected to have a nickel allergy. 9. Subjects with bleeding disorders or active anticoagulation that cannot be stopped for a few days close to the time of the surgical procedure. 10. Subjects who decline to provide written consent or follow-up. 11. Subjects who are pregnant, plan on becoming pregnant, or are breastfeeding during the study period. Subjects who are female of child-bearing potential must have a negative pregnancy test at baseline visit and, if sexually active, must be using a medically acceptable method of contraception for the duration of the study participation. 12. Subjects who have an active systemic infection or are immunocompromised. 13. Subjects who have an active or existing skin disorder or irritation, which, at the physician's discretion, precludes the use of skin gel electrodes. 14. Subjects who currently require or are likely to require Magnetic Resonance Imaging (MRI) within the MRI exclusion zone: the entire StimRouter lead must be at least 50 cm from the center of the MR system's bore (the iso-center) and at least 16 cm outside of the MR coil measured from the edge of the MR coil. 15. Subjects who have a history of adverse reactions to local anesthetic (e.g., lidocaine). 16. Subjects who are participating in any other study that could affect the outcome of the StimRouter study, such as a spinal stimulation study, without Sponsor approval. 17. Subjects who are in litigation or who have pending or an active worker's compensation claim. 18. Subjects with less than one year of life expectancy.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Brief Pain Inventory (BPI): Number of Participants With a Pain Reduction of Greater Than or Equal to 30% | Baseline and at 3-month follow-up. | The average pain at rest was assessed using a numerical (0-10) rating scale (NRS) on the Brief Pain Inventory (BPI) Short Form (SF). A higher score indicates worse pain (10=worst pain imaginable) and zero indicates 'no pain at all'. A pain reduction of greater than or equal to 30% on the NRS was considered to be clinically relevant. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Patient Global Impression of Improvement With Treatment Will be Assessed Using the Patient Global Impression of Change Scale (PGIC). | at 3 month follow-up | Patient Global Impression of Change in activity limitations, symptoms, emotions and overall life quality related to their painful condition (Range 1 to 7, with 1 indicating no change and 7 indicating a great deal better/considerable improvement). |
| Worst Pain in the Last 24 Hours Will be Assessed Using 7-day Patient Pain Diary Scores for BPI SF #3. | at baseline and 3 month follow-up | Worst pain in the last 24 hours assessed using 7-day patient pain diary scores for BPI ranging from 0 to 10, with 0 indicating no pain and 10 indicating pain as bad as you can imagine. Change from baseline to Month 3 was compared. |
| Patient Satisfaction Will be Assessed Using a Patient Satisfaction Survey | at the 3-month follow-up | Patient satisfaction with the StimRouter System was rated on a numerical rating scale (range 0 to 10), with 0 indicating not satisfied at all and 10 indicating completely satisfied. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Active Stimulation Treatment Subjects implanted with the StimRouter lead and randomized to receive active stimulation. | 45 |
| Control Subjects implanted with the StimRouter lead and randomized to receive no electrical stimulation. | 49 |
| Total | 94 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Adverse Event | 1 | 1 |
| Overall Study | Lack of Efficacy | 1 | 0 |
| Overall Study | not available at primary outcome visit | 2 | 4 |
Baseline characteristics
| Characteristic | Active Stimulation Treatment | Control | Total |
|---|---|---|---|
| Age, Continuous | 52.8 years STANDARD_DEVIATION 10 | 53.2 years STANDARD_DEVIATION 12.1 | 53.0 years STANDARD_DEVIATION 11.1 |
| Region of Enrollment United States | 45 participants | 49 participants | 94 participants |
| Sex: Female, Male Female | 25 Participants | 30 Participants | 55 Participants |
| Sex: Female, Male Male | 20 Participants | 19 Participants | 39 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 19 / 45 | 16 / 49 |
| serious Total, serious adverse events | 9 / 45 | 11 / 49 |
Outcome results
Primary
Brief Pain Inventory (BPI): Number of Participants With a Pain Reduction of Greater Than or Equal to 30%
The average pain at rest was assessed using a numerical (0-10) rating scale (NRS) on the Brief Pain Inventory (BPI) Short Form (SF). A higher score indicates worse pain (10=worst pain imaginable) and zero indicates 'no pain at all'. A pain reduction of greater than or equal to 30% on the NRS was considered to be clinically relevant.
Time frame: Baseline and at 3-month follow-up.
Population: Intent to treat (ITT) population was analyzed.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| StimRouter - Active Stimulation | Brief Pain Inventory (BPI): Number of Participants With a Pain Reduction of Greater Than or Equal to 30% | 17 participants |
| StimRouter - Control | Brief Pain Inventory (BPI): Number of Participants With a Pain Reduction of Greater Than or Equal to 30% | 5 participants |
p-value: 0.0048Cochran-Mantel-Haenszel
Secondary
Patient Global Impression of Improvement With Treatment Will be Assessed Using the Patient Global Impression of Change Scale (PGIC).
Patient Global Impression of Change in activity limitations, symptoms, emotions and overall life quality related to their painful condition (Range 1 to 7, with 1 indicating no change and 7 indicating a great deal better/considerable improvement).
Time frame: at 3 month follow-up
Population: All patients who completed the 3 month Global Impression of Change questionnaire were included. Four patients in each study arm failed to complete the questionnaire.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| StimRouter - Active Stimulation | Patient Global Impression of Improvement With Treatment Will be Assessed Using the Patient Global Impression of Change Scale (PGIC). | 4.8 units on a scale | Standard Deviation 1.5 |
| StimRouter - Control | Patient Global Impression of Improvement With Treatment Will be Assessed Using the Patient Global Impression of Change Scale (PGIC). | 2.5 units on a scale | Standard Deviation 1.9 |
p-value: <0.0001t-test, 2 sided
Secondary
Patient Satisfaction Will be Assessed Using a Patient Satisfaction Survey
Patient satisfaction with the StimRouter System was rated on a numerical rating scale (range 0 to 10), with 0 indicating not satisfied at all and 10 indicating completely satisfied.
Time frame: at the 3-month follow-up
Population: All subjects who completed the survey at Month 3 were included in this analysis. Four subjects in each study arm (4/45 Treatment; 4/49 Control) failed to complete the satisfaction survey.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| StimRouter - Active Stimulation | Patient Satisfaction Will be Assessed Using a Patient Satisfaction Survey | 7.3 units on a scale | Standard Deviation 2.9 |
| StimRouter - Control | Patient Satisfaction Will be Assessed Using a Patient Satisfaction Survey | 3.0 units on a scale | Standard Deviation 3.6 |
p-value: <0.0001t-test, 2 sided
Secondary
Worst Pain in the Last 24 Hours Will be Assessed Using 7-day Patient Pain Diary Scores for BPI SF #3.
Worst pain in the last 24 hours assessed using 7-day patient pain diary scores for BPI ranging from 0 to 10, with 0 indicating no pain and 10 indicating pain as bad as you can imagine. Change from baseline to Month 3 was compared.
Time frame: at baseline and 3 month follow-up
Population: All available data were analyzed from both treatment arms.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| StimRouter - Active Stimulation | Worst Pain in the Last 24 Hours Will be Assessed Using 7-day Patient Pain Diary Scores for BPI SF #3. | -2.4 units on a scale | Standard Deviation 2.3 |
| StimRouter - Control | Worst Pain in the Last 24 Hours Will be Assessed Using 7-day Patient Pain Diary Scores for BPI SF #3. | -0.3 units on a scale | Standard Deviation 1.6 |
p-value: <0.0001t-test, 2 sided