Trial Outcomes & Findings for Subcutaneous Nerve Stimulation for Failed Back Surgery Syndrome (FBSS) Patients (NCT NCT01818297)
NCT ID: NCT01818297
Last Updated: 2017-09-21
Results Overview
Number of responders in Treatment and Control groups. Subjects reported typical back pain (0=no pain, 10=worst pain) during the Baseline (BL) and Blinded Phase (M3) periods. Percentage reduction in average back pain was calculated as (BL-M3)/BL. Subjects with at least a 50% reduction in average back pain between Baseline and Month 3, with no increase in prescribed pain medications, were considered responders.
TERMINATED
NA
137 participants
Baseline to 3 months
2017-09-21
Participant Flow
This study enrolled adult patients with chronic, intractable post-surgical back pain. First enrollment was in April 2013. Enrollment was suspended in September 2014 due to slow enrollment. The last subject visit was in March 2016. The planned enrollment was 323 subjects, with 218 randomized. Actual enrollment was 137 subjects with 62 randomized.
Of the 137 enrolled subjects, 62 were implanted and randomized. Of the 75 subjects who discontinued from the study prior to randomization, 54 did not meet inclusion/exclusion criteria, 12 withdrew consent or declined device implant, 3 discontinued due to study suspension, and 6 discontinued for other reasons.
Participant milestones
| Measure |
Treatment
Treatment settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
Control
Control settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
|---|---|---|
|
Blinded Phase (Randomization - 3 Months)
STARTED
|
32
|
30
|
|
Blinded Phase (Randomization - 3 Months)
Week 1
|
32
|
30
|
|
Blinded Phase (Randomization - 3 Months)
Week 6
|
32
|
29
|
|
Blinded Phase (Randomization - 3 Months)
COMPLETED
|
32
|
29
|
|
Blinded Phase (Randomization - 3 Months)
NOT COMPLETED
|
0
|
1
|
|
Open Label Phase (3-12 Months)
STARTED
|
32
|
29
|
|
Open Label Phase (3-12 Months)
COMPLETED
|
14
|
19
|
|
Open Label Phase (3-12 Months)
NOT COMPLETED
|
18
|
10
|
Reasons for withdrawal
| Measure |
Treatment
Treatment settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
Control
Control settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
|---|---|---|
|
Blinded Phase (Randomization - 3 Months)
Adverse Event
|
0
|
1
|
|
Open Label Phase (3-12 Months)
Physician Decision
|
1
|
0
|
|
Open Label Phase (3-12 Months)
Early study closure
|
17
|
10
|
Baseline Characteristics
Subcutaneous Nerve Stimulation for Failed Back Surgery Syndrome (FBSS) Patients
Baseline characteristics by cohort
| Measure |
Treatment
n=32 Participants
Treatment settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
Control
n=30 Participants
Control settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
Total
n=62 Participants
Total of all reporting groups
|
|---|---|---|---|
|
Age, Continuous
|
60.6 years
STANDARD_DEVIATION 13.1 • n=93 Participants
|
59.8 years
STANDARD_DEVIATION 13.7 • n=4 Participants
|
60.2 years
STANDARD_DEVIATION 13.3 • n=27 Participants
|
|
Sex: Female, Male
Female
|
18 Participants
n=93 Participants
|
16 Participants
n=4 Participants
|
34 Participants
n=27 Participants
|
|
Sex: Female, Male
Male
|
14 Participants
n=93 Participants
|
14 Participants
n=4 Participants
|
28 Participants
n=27 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
0 Participants
n=93 Participants
|
1 Participants
n=4 Participants
|
1 Participants
n=27 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
32 Participants
n=93 Participants
|
29 Participants
n=4 Participants
|
61 Participants
n=27 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Race (NIH/OMB)
Asian
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Race (NIH/OMB)
Black or African American
|
2 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
2 Participants
n=27 Participants
|
|
Race (NIH/OMB)
White
|
30 Participants
n=93 Participants
|
28 Participants
n=4 Participants
|
58 Participants
n=27 Participants
|
|
Race (NIH/OMB)
More than one race
|
0 Participants
n=93 Participants
|
2 Participants
n=4 Participants
|
2 Participants
n=27 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Region of Enrollment
United States
|
32 participants
n=93 Participants
|
30 participants
n=4 Participants
|
62 participants
n=27 Participants
|
|
Back pain
|
6.77 units on a scale
STANDARD_DEVIATION 1.25 • n=93 Participants
|
6.66 units on a scale
STANDARD_DEVIATION 0.88 • n=4 Participants
|
6.71 units on a scale
STANDARD_DEVIATION 1.08 • n=27 Participants
|
PRIMARY outcome
Timeframe: Baseline to 3 monthsNumber of responders in Treatment and Control groups. Subjects reported typical back pain (0=no pain, 10=worst pain) during the Baseline (BL) and Blinded Phase (M3) periods. Percentage reduction in average back pain was calculated as (BL-M3)/BL. Subjects with at least a 50% reduction in average back pain between Baseline and Month 3, with no increase in prescribed pain medications, were considered responders.
Outcome measures
| Measure |
Treatment
n=32 Participants
Treatment settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
Control
n=30 Participants
Control settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
|---|---|---|
|
Number of Back Pain Responders (Subjects Who Achieve at Least a 50% Reduction in Average Back Pain With no Increase in Prescription Pain Medications) From Baseline to Month 3 Post-device Activation.
|
9 Participants
|
5 Participants
|
SECONDARY outcome
Timeframe: Baseline to 3 monthsCompare the difference in average improvement in disability (as measured by Oswestry Disability Index (ODI)) from Baseline to Month 3 between the Treatment and Control groups. ODI ranges from 0% (no disability) -100% (greatest disability). Change is calculated as Baseline - Month 3 with a positive change indicating improvement in disability. Subjects with missing Baseline and/or Month 3 ODI assessments were counted as no change (Baseline - Month 3 = 0).
Outcome measures
| Measure |
Treatment
n=32 Participants
Treatment settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
Control
n=30 Participants
Control settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
|---|---|---|
|
Functional Disability
|
9.8 units on a scale
Standard Deviation 14.3
|
10.0 units on a scale
Standard Deviation 12.1
|
SECONDARY outcome
Timeframe: 3 monthsPopulation: The analysis population includes all randomized subjects, with the exception of one subject in the Control group who did not have a satisfaction value. This subject was excluded from the analysis.
Compare difference in number of subjects satisfied with therapy between the Treatment and Control groups at Month 3. Subjects who reported they were very or somewhat satisfied with the therapy were counted as satisfied. Subjects with no satisfaction response were excluded from the analysis.
Outcome measures
| Measure |
Treatment
n=32 Participants
Treatment settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
Control
n=29 Participants
Control settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
|---|---|---|
|
Subject Satisfaction
|
25 Participants
|
22 Participants
|
SECONDARY outcome
Timeframe: Baseline to 3 monthsCompare the average change in quality of life (as measured by Short Form Health Survey (SF36 v2): Physical component score (PCS)) from Baseline to Month 3 between subjects in the Treatment and Control groups. The PCS ranges from 0 (worst possible physicial quality of life) to 100 (best possible physical quality of life). Change was calculated as Month 3 - Baseline, with a positive difference indicating improvement in physical quality of life. Subjects with missing Baseline and/or Month 3 SF-36: PCS assessments were counted as no change (Month 3 - Baseline = 0).
Outcome measures
| Measure |
Treatment
n=32 Participants
Treatment settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
Control
n=30 Participants
Control settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
|---|---|---|
|
Quality of Life: Physical
|
3.6 units on a scale
Standard Deviation 8.6
|
3.1 units on a scale
Standard Deviation 7.1
|
SECONDARY outcome
Timeframe: Baseline to 3 monthsCompare the average change in quality of life (as measured by Short Form Health Survey (SF36 v2): Mental component score (MCS)) from Baseline to Month 3 between subjects in the Treatment and Control groups. The MCS ranges from 0 (worst possible mental quality of life) to 100 (best possible mental quality of life). Change was calculated as Month 3 - Baseline, with a positive difference indicating improvement in mental quality of life. Subjects with missing Baseline and/or Month 3 SF-36: MCS assessments were counted as no change (Month 3 - Baseline = 0).
Outcome measures
| Measure |
Treatment
n=32 Participants
Treatment settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
Control
n=30 Participants
Control settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
|---|---|---|
|
Quality of Life: Mental
|
1.9 units on a scale
Standard Deviation 10.0
|
1.4 units on a scale
Standard Deviation 9.6
|
SECONDARY outcome
Timeframe: Baseline to 3 monthsCompare the average improvement in worst back pain from Baseline to Month 3 between the Treatment and Control groups. Subjects reported worst back pain (0 (no pain) - 10 (worst pain)) during the Baseline and Blinded Phase (Month 3) periods. Change was calculated as Baseline - Month 3, with a positive change indicating improvement in worst back pain.
Outcome measures
| Measure |
Treatment
n=32 Participants
Treatment settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
Control
n=30 Participants
Control settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
|---|---|---|
|
Worst Back Pain
|
2.7 units on a scale
Standard Deviation 2.6
|
1.6 units on a scale
Standard Deviation 1.9
|
Adverse Events
Treatment
Control
Serious adverse events
| Measure |
Treatment
n=32 participants at risk
Treatment settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
Control
n=30 participants at risk
Control settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
|---|---|---|
|
Infections and infestations
Implant site infection
|
3.1%
1/32 • Number of events 1 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
0.00%
0/30 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
|
Respiratory, thoracic and mediastinal disorders
Pulmonary embolism
|
3.1%
1/32 • Number of events 1 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
0.00%
0/30 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
Other adverse events
| Measure |
Treatment
n=32 participants at risk
Treatment settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
Control
n=30 participants at risk
Control settings of Medtronic PrimeAdvanced® neurostimulator system implant
PrimeAdvanced® neurostimulator system: Neurostimulator and associated components
|
|---|---|---|
|
Musculoskeletal and connective tissue disorders
Back pain
|
12.5%
4/32 • Number of events 4 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
6.7%
2/30 • Number of events 2 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
|
General disorders
Implant site pain
|
9.4%
3/32 • Number of events 3 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
6.7%
2/30 • Number of events 2 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
|
Musculoskeletal and connective tissue disorders
Pain in extremity
|
6.2%
2/32 • Number of events 2 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
3.3%
1/30 • Number of events 1 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
|
Musculoskeletal and connective tissue disorders
Spinal osteoarthritis
|
0.00%
0/32 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
10.0%
3/30 • Number of events 3 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
|
Gastrointestinal disorders
Nausea
|
0.00%
0/32 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
6.7%
2/30 • Number of events 2 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
|
Nervous system disorders
Burning sensation
|
6.2%
2/32 • Number of events 2 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
0.00%
0/30 • The adverse events summarized by treatment arm are all adverse events that were collected during the Blinded Phase of the study (from Randomization through the Month 3 visit).
There were 175.6 total months of subject follow-up during this time: 94.2 months in the Treatment group and 81.4 months in the Control group.
|
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee Disclosure restrictions on the PI allow for the sponsor to review results communications prior to public release and to embargo communications regarding trial results for a period that is less than or equal to 60 days from the time submitted to sponsor for review. The sponsor is also allowed to require changes for technical correctness and to protect confidential information, copyrightable or patentable material; and when reasonably requested, extend the embargo up to an additional 90 days.
- Publication restrictions are in place
Restriction type: OTHER