Trial Outcomes & Findings for A Safety and Effectiveness Study of Intraspinal Gabapentin (MDT2004) for the Treatment of Chronic Pain (NCT NCT00414466)

Last Updated: 2013-08-23

Results Overview

Average pain score calculated over last 7 days of baseline minus average pain score calculated over last 7 days of follow-up using the Numeric Pain Rating Scale where 0=no pain, 10=worst possible pain.

Recruitment status

TERMINATED

Study phase

PHASE2

Target enrollment

254 participants

Primary outcome timeframe

Baseline and Post-randomization Day 22

Results posted on

2013-08-23

Participant Flow

A total of 254 subjects were enrolled into the study between December 2006 and October 2009.

During a 2-week screening period subjects were required to meet eligibility criteria including maintaining stable pain medications and demonstrating a numerical pain rating score of 6 or greater averaged over the last 7 days of screening. A total of 170 subjects met eligibility criteria, were implanted with an infusion system and were randomized.

Participant milestones

Participant milestones
Measure	1 Placebo (0mg/Day) Intraspinal Placebo delivered continuously for 29 days via an implantable infusion system	2 Gabapentin Low (1mg/Day) Intraspinal Gabapentin Low (1mg/day) delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose	3 Gabapentin Medium (6mg/Day) Intraspinal Gabapentin Medium (6mg/day) delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose	4 Gabapentin High (30mg/Day) Intraspinal Gabapentin High (30mg/day) delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose
Overall Study STARTED	44	42	41	43
Overall Study COMPLETED	42	42	40	42
Overall Study NOT COMPLETED	2	0	1	1

Reasons for withdrawal

Reasons for withdrawal
Measure	1 Placebo (0mg/Day) Intraspinal Placebo delivered continuously for 29 days via an implantable infusion system	3 Gabapentin Medium (6mg/Day) Intraspinal Gabapentin Medium (6mg/day) delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose	4 Gabapentin High (30mg/Day) Intraspinal Gabapentin High (30mg/day) delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose
Overall Study Adverse Event	0	1	1
Overall Study Lack of Efficacy	1	0	0
Overall Study Withdrawn by Sponsor	1	0	0

Baseline Characteristics

A Safety and Effectiveness Study of Intraspinal Gabapentin (MDT2004) for the Treatment of Chronic Pain

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	1 Placebo n=44 Participants Intraspinal Placebo delivered continuously for 29 days via an implantable infusion system	2 Gabapentin Low n=42 Participants Intraspinal Gabapentin Low delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose	3 Gabapentin Medium n=41 Participants Intraspinal Gabapentin Medium delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose	4 Gabapentin High n=43 Participants Intraspinal Gabapentin High delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose	Total n=170 Participants Total of all reporting groups
Age, Categorical <=18 years	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants
Age, Categorical Between 18 and 65 years	39 Participants n=5 Participants	41 Participants n=7 Participants	40 Participants n=5 Participants	40 Participants n=4 Participants	160 Participants n=21 Participants
Age, Categorical >=65 years	5 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants	3 Participants n=4 Participants	10 Participants n=21 Participants
Age Continuous	51.8 years STANDARD_DEVIATION 11.2 • n=5 Participants	50.1 years STANDARD_DEVIATION 9.9 • n=7 Participants	48.1 years STANDARD_DEVIATION 9.4 • n=5 Participants	48.3 years STANDARD_DEVIATION 11.1 • n=4 Participants	49.6 years STANDARD_DEVIATION 10.5 • n=21 Participants
Sex: Female, Male Female	27 Participants n=5 Participants	28 Participants n=7 Participants	20 Participants n=5 Participants	23 Participants n=4 Participants	98 Participants n=21 Participants
Sex: Female, Male Male	17 Participants n=5 Participants	14 Participants n=7 Participants	21 Participants n=5 Participants	20 Participants n=4 Participants	72 Participants n=21 Participants
Region of Enrollment United States	44 participants n=5 Participants	42 participants n=7 Participants	41 participants n=5 Participants	43 participants n=4 Participants	170 participants n=21 Participants

PRIMARY outcome

Timeframe: Baseline and Post-randomization Day 22

Population: Primary efficacy analysis was performed on the 167 randomized subjects that completed at least 4 days of the electronic pain diary during the last 7 days prior to the Day 22 or Early Termination Visit as per protocol. No imputation methods were used.

Outcome measures

Outcome measures
Measure	1 Placebo n=43 Participants Intraspinal Placebo delivered continuously for 29 days via an implantable infusion system	2 Gabapentin Low n=42 Participants Intraspinal Gabapentin Low (1mg/day) delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose	3 Gabapentin Medium n=41 Participants Intraspinal Gabapentin Medium (6mg/day) delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose	4 Gabapentin High n=41 Participants Intraspinal Gabapentin High (30mg/day) delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose
Changes in a Pain Rating Scale After 3 Weeks of Blinded Treatment.	0.48 Scores on a scale Standard Deviation 1.52	0.40 Scores on a scale Standard Deviation 1.33	0.10 Scores on a scale Standard Deviation 0.99	-0.02 Scores on a scale Standard Deviation 1.11

PRIMARY outcome

Timeframe: Randomization to Post-randomization Day 29 (includes dose reduction)

Population: All randomized subjects were included as per protocol.

Evaluation of adverse event profiles between placebo and active treatment groups.

Outcome measures

Outcome measures
Measure	1 Placebo n=44 Participants Intraspinal Placebo delivered continuously for 29 days via an implantable infusion system	2 Gabapentin Low n=42 Participants Intraspinal Gabapentin Low (1mg/day) delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose	3 Gabapentin Medium n=41 Participants Intraspinal Gabapentin Medium (6mg/day) delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose	4 Gabapentin High n=43 Participants Intraspinal Gabapentin High (30mg/day) delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose
Number of Participants With Treatment-emergent Adverse Events	40 Participants	32 Participants	37 Participants	36 Participants

SECONDARY outcome

Timeframe: Baseline to Post-randomization Day 22

Population: All 170 randomized subjects were included as per protocol. Subjects experiencing an intolerable adverse event, discontinuing due to an adverse event or lack of efficacy, or not providing data were considered non-responders.

Responders were subjects that reported at least a 30% decrease in average daily pain scores between baseline and Day 22.

Outcome measures

Outcome measures
Measure	1 Placebo n=44 Participants Intraspinal Placebo delivered continuously for 29 days via an implantable infusion system	2 Gabapentin Low n=42 Participants Intraspinal Gabapentin Low (1mg/day) delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose	3 Gabapentin Medium n=41 Participants Intraspinal Gabapentin Medium (6mg/day) delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose	4 Gabapentin High n=43 Participants Intraspinal Gabapentin High (30mg/day) delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose
Responder Analysis Between Active Treatment and Placebo Groups.	4 Participants	4 Participants	1 Participants	2 Participants

Adverse Events

1 Placebo

Serious events: 1 serious events

Other events: 30 other events

Deaths: 0 deaths

2 Gabapentin Low

Serious events: 1 serious events

Other events: 21 other events

Deaths: 0 deaths

3 Gabapentin Medium

Serious events: 4 serious events

Other events: 27 other events

Deaths: 0 deaths

4 Gabapentin High

Serious events: 4 serious events

Other events: 25 other events

Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure	1 Placebo n=44 participants at risk Intraspinal Placebo delivered continuously for 29 days via an implantable infusion system	2 Gabapentin Low n=42 participants at risk Intraspinal Gabapentin Low delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose	3 Gabapentin Medium n=41 participants at risk Intraspinal Gabapentin Medium delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose	4 Gabapentin High n=43 participants at risk Intraspinal Gabapentin High delivered continuously for 22 days via an implantable infusion system followed by 7 days of infusion at half dose
Infections and infestations Catheter site infection	0.00% 0/44 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/42 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/41 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	2.3% 1/43 • Number of events 1 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.
Infections and infestations Implant site infection	2.3% 1/44 • Number of events 1 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/42 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/41 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/43 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.
Infections and infestations Osteomyelitis	0.00% 0/44 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	2.4% 1/42 • Number of events 1 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/41 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/43 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.
Blood and lymphatic system disorders Bone marrow disorder	0.00% 0/44 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/42 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	2.4% 1/41 • Number of events 1 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/43 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.
Psychiatric disorders Suicidal ideation	0.00% 0/44 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/42 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/41 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	2.3% 1/43 • Number of events 1 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.
Nervous system disorders Neuropathic pain	0.00% 0/44 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/42 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	2.4% 1/41 • Number of events 1 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/43 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.
Nervous system disorders Radiculopathy	0.00% 0/44 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/42 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/41 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	2.3% 1/43 • Number of events 1 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.
Gastrointestinal disorders Oesophageal spasm	0.00% 0/44 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/42 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/41 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	2.3% 1/43 • Number of events 1 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.
General disorders Pain	0.00% 0/44 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/42 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	2.4% 1/41 • Number of events 1 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/43 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.
Injury, poisoning and procedural complications Closed head injury	0.00% 0/44 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/42 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	2.4% 1/41 • Number of events 1 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/43 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.
Injury, poisoning and procedural complications Overdose	0.00% 0/44 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/42 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/41 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	2.3% 1/43 • Number of events 1 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.
Injury, poisoning and procedural complications Therapeutic agent toxicity	0.00% 0/44 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/42 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	2.4% 1/41 • Number of events 1 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.	0.00% 0/43 • Adverse events are reported through 29 days post-randomization, including 22 days of dosing at the randomized dose and 7 days of dose reduction. All randomized subjects were included in adverse event summaries.

Other adverse events

Additional Information

Robert Spencer, Clinical Research Manager

Medtronic Neuromodulation

Phone: (763) 514-0253

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place

Restriction type: LTE60