Complex Regional Pain Syndrome (CRPS)
Conditions
Keywords
Complex Regional Pain Syndrome (CRPS), Chronic pain, SJM-CIP-10113
Brief summary
The purpose of this prospective, multicenter, single arm post-approval study is to demonstrate continued safety of the Axium and Proclaim Neurostimulator System for dorsal root ganglion (DRG) stimulation. The primary endpoint is the 12-month serious adverse event rate for permanent implants.
Detailed description
A maximum of 426 adult subjects with moderate to severe chronic, intractable, pain of the lower limbs due to CRPS types I and II will undergo a trial of the Axium or Proclaim Neurostimulator System across up to 45 study sites in the United States. Only subjects who report a 50% or greater reduction in overall pain intensity through direct patient-reported percentage of pain relief will receive the permanent implant. Subjects will then return to the office for follow-up at 1, 3, 6 and 12 months post-permanent implant.
Interventions
DEVICEDorsal Root Ganglion (DRG) Stimulation (Axium™ Neurostimulator System)
Electrical stimulation of the DRG using the Axium™ Neurostimulator System
DEVICEDorsal Root Ganglion (DRG) Stimulation (Proclaim™ Neurostimulator System)
Electrical Stimulation of the DRG using the Proclaim™ Neurostimulator System.
Sponsors
Abbott Medical Devices
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
22 Years to 75 Years
Healthy volunteers
No
Inclusion criteria
* Subject is male or female between ≥ 22 and ≤ 75 years of age. * Subject has moderate to severe chronic intractable pain of the lower limbs resulting from Complex Regional Pain Syndrome (CRPS) types I or II. * Subject has a baseline Visual Analogue Scale (VAS) of ≥ 60 mm for overall pain at the time of the baseline assessment. * Subject is willing and able to comply with the study requirements. * Subject is able to provide written informed consent.
Exclusion criteria
* Subject has an active implantable medical device including but not limited to cardiac pacemakers and cardiac defibrillators. * Subject is currently involved in medically related litigation, including workers compensation. * Subject has a life expectancy of less than one year. * Subject is pregnant or of child bearing potential and not using adequate contraception as determined by the investigator. * Subject has, or plans to have, a spinal cord stimulation system or infusion pump system implanted. * Subject has, or plans to have, a peripheral nerve stimulation system (PNS) or peripheral nerve field stimulation system (PNfS) implanted. * Subject is considered to be a poor surgical or study candidate, which may include, but is not limited to the following: any medical, social, or psychological problem that could complicate the implant procedure and/or recovery from the implant procedure or could complicate the required procedures and evaluations of the study in the judgment of the investigator.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Rate of Serious Adverse Events (SAEs) | throughout 12 month study | The serious adverse event rate for subjects receiving the permanent DRG implantable pulse generator (IPG) was analyzed using Kaplan-Meier method on subjects who received the permanent Axium or Proclaim DRG IPG (N = 296). While 426 patients were enrolled, only 296 received the permanent implant. The primary population is 296. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Percent Change From Baseline to 12 Months Post-permanent Implant for Overall Pain Intensity Measured Using the Visual Analog Scale (VAS) | 12 months | The VAS is a common, self-administered measure in which subjects rate their pain intensity by marking a vertical line through a 100 mm horizontal line anchored by word descriptors on each end (no pain to worst imaginable pain). The distance between the beginning of the horizontal line and the vertical line is measured to produce a score between 0 and 100 mm (or 0 to 10 cm). A higher score indicates higher pain intensity and a 30% reduction in VAS score from baseline to follow-up is considered clinically relevant. |
| Change From Baseline to 12 Months Post-permanent Implant for Physical Function Measured Using the Patient Reported Outcomes Measurement Information System-29 (PROMIS-29) Physical Function Scale | 12 months | The PROMIS-29 Profile is an instrument made up of seven individual short forms (physical function, anxiety, depression, fatigue, sleep disturbance, ability to participate in social roles and activities, pain interference) that are scored individually. The instrument also includes a single pain intensity item which is reported as its raw score (e.g., 0 to 10). Each item has five response options ranging in value from 1 to 5, except for the Pain Intensity item which has eleven response options ranging in value from 0 to 10. A raw score is created from each short form that makes up the Profile. Raw scores are calculated by summing the values of the response to each question within each domain. |
| Change From Baseline to 12 Months Post-permanent Implant for Quality of Life Measured Using the PROMIS Global Health Scale | 12 months | The PROMIS Global Health short form is a validated, 10-item instrument designed to assess multiple health domains. The questionnaire yields a total score and sub-scale scores for Global Physical and Mental Health. Each question has potential five response options ranging in value from one to five to give a total score ranging from 10 to 50. All questions must be answered to arrive at a total score as one or more missing responses will render scores unusable. Scores are converted into t-scores where the average for the general US population is 50 and the SD is 10. Higher scores indicate better global health. |
Countries
United States
Participant flow
Recruitment details
The study enrolled a total of 426 subjects at 44 investigational sites. The first subject was enrolled in August 2016 and the last subject in December 2019. Completion of enrollment and follow-up in the study occurred in September 2021.
Participants by arm
| Arm | Count |
|---|---|
| Dorsal Root Ganglion (DRG) Stimulation Dorsal Root Ganglion (DRG) Stimulation (Axium™ Neurostimulator System): Electrical stimulation of the DRG using the Axium™ Neurostimulator System
Dorsal Root Ganglion (DRG) Stimulation (Proclaim™ Neurostimulator System): Electrical Stimulation of the DRG using the Proclaim™ Neurostimulator System. | 426 |
| Total | 426 |
Withdrawals & dropouts
| Period | Reason | FG000 |
|---|---|---|
| Overall Study | Adverse Event | 14 |
| Overall Study | Another Device Implanted | 1 |
| Overall Study | Death | 3 |
| Overall Study | Device Explanted | 1 |
| Overall Study | Device Has Been Turned Off Since Jan 2019 | 1 |
| Overall Study | Health Issues | 1 |
| Overall Study | Insurance Denial | 8 |
| Overall Study | Lost to Follow-up | 26 |
| Overall Study | No Perm Implant, Active Pain Pump Implanted | 1 |
| Overall Study | Patient Did not Obtain at Least 50% Pain Relief | 1 |
| Overall Study | Screen Failure | 1 |
| Overall Study | Sponsor Request | 6 |
| Overall Study | Subject and/or Family Request | 64 |
| Overall Study | Subject Implant at Another Facility | 1 |
| Overall Study | Subject Participation Terminated by Investigator | 17 |
| Overall Study | Trial Failure | 81 |
| Overall Study | Used Different Battery not Approved for Study at Time of Perm | 1 |
Baseline characteristics
| Characteristic | Dorsal Root Ganglion (DRG) Stimulation |
|---|---|
| Age, Continuous | 52.7 years STANDARD_DEVIATION 13.8 |
| Complex Regional Pain Syndrome (CRPS) CRPS I | 301 Participants |
| Complex Regional Pain Syndrome (CRPS) CRPS II | 125 Participants |
| Ethnicity (NIH/OMB) Hispanic or Latino | 36 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 375 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 15 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 2 Participants |
| Race (NIH/OMB) Asian | 4 Participants |
| Race (NIH/OMB) Black or African American | 32 Participants |
| Race (NIH/OMB) More than one race | 17 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 10 Participants |
| Race (NIH/OMB) White | 361 Participants |
| Region of Enrollment United States | 426 participants |
| Sex: Female, Male Female | 259 Participants |
| Sex: Female, Male Male | 167 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 3 / 426 |
| other Total, other adverse events | 5 / 426 |
| serious Total, serious adverse events | 26 / 426 |
Outcome results
Primary
Rate of Serious Adverse Events (SAEs)
The serious adverse event rate for subjects receiving the permanent DRG implantable pulse generator (IPG) was analyzed using Kaplan-Meier method on subjects who received the permanent Axium or Proclaim DRG IPG (N = 296). While 426 patients were enrolled, only 296 received the permanent implant. The primary population is 296.
Time frame: throughout 12 month study
Population: The number of participants analyzed includes subjects who were available at that time of analysis.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Dorsal Root Ganglion (DRG) Stimulation | Rate of Serious Adverse Events (SAEs) | 8.7 percentage of events | Standard Error 1.7 |
Secondary
Change From Baseline to 12 Months Post-permanent Implant for Physical Function Measured Using the Patient Reported Outcomes Measurement Information System-29 (PROMIS-29) Physical Function Scale
The PROMIS-29 Profile is an instrument made up of seven individual short forms (physical function, anxiety, depression, fatigue, sleep disturbance, ability to participate in social roles and activities, pain interference) that are scored individually. The instrument also includes a single pain intensity item which is reported as its raw score (e.g., 0 to 10). Each item has five response options ranging in value from 1 to 5, except for the Pain Intensity item which has eleven response options ranging in value from 0 to 10. A raw score is created from each short form that makes up the Profile. Raw scores are calculated by summing the values of the response to each question within each domain.
Time frame: 12 months
Population: The number of participants analyzed includes subjects who were available at that time of analysis.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Dorsal Root Ganglion (DRG) Stimulation | Change From Baseline to 12 Months Post-permanent Implant for Physical Function Measured Using the Patient Reported Outcomes Measurement Information System-29 (PROMIS-29) Physical Function Scale | 5.13 percent | Standard Deviation 6.28 |
Secondary
Change From Baseline to 12 Months Post-permanent Implant for Quality of Life Measured Using the PROMIS Global Health Scale
The PROMIS Global Health short form is a validated, 10-item instrument designed to assess multiple health domains. The questionnaire yields a total score and sub-scale scores for Global Physical and Mental Health. Each question has potential five response options ranging in value from one to five to give a total score ranging from 10 to 50. All questions must be answered to arrive at a total score as one or more missing responses will render scores unusable. Scores are converted into t-scores where the average for the general US population is 50 and the SD is 10. Higher scores indicate better global health.
Time frame: 12 months
Population: The number of participants analyzed includes subjects who were available at that time of analysis.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Dorsal Root Ganglion (DRG) Stimulation | Change From Baseline to 12 Months Post-permanent Implant for Quality of Life Measured Using the PROMIS Global Health Scale | Physical Health | 6.22 percent | Standard Deviation 7.25 |
| Dorsal Root Ganglion (DRG) Stimulation | Change From Baseline to 12 Months Post-permanent Implant for Quality of Life Measured Using the PROMIS Global Health Scale | Mental Health | 4.42 percent | Standard Deviation 8.19 |
Secondary
Percent Change From Baseline to 12 Months Post-permanent Implant for Overall Pain Intensity Measured Using the Visual Analog Scale (VAS)
The VAS is a common, self-administered measure in which subjects rate their pain intensity by marking a vertical line through a 100 mm horizontal line anchored by word descriptors on each end (no pain to worst imaginable pain). The distance between the beginning of the horizontal line and the vertical line is measured to produce a score between 0 and 100 mm (or 0 to 10 cm). A higher score indicates higher pain intensity and a 30% reduction in VAS score from baseline to follow-up is considered clinically relevant.
Time frame: 12 months
Population: The number of participants analyzed includes subjects who were available at that time of analysis.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Dorsal Root Ganglion (DRG) Stimulation | Percent Change From Baseline to 12 Months Post-permanent Implant for Overall Pain Intensity Measured Using the Visual Analog Scale (VAS) | 44.48 percent | Standard Deviation 34.15 |