Trial · NCT00636636

Safety and Efficacy of Gabapentin in Postherpetic Neuralgia

NCT00636636, Phase 3, Completed, Depomed; results first posted 2012-01-13

3 sourcestrials-2026-11-12-0.5.0

Cite this record

ConductScience Library. Safety and Efficacy of Gabapentin in Postherpetic Neuralgia. Trials, record NCT00636636. Release trials-2026-11-12-0.5.0, 12 Nov 2026. https://conductscience.org/library/trials/NCT00636636

On this page

Trial

As registered on ClinicalTrials.gov, in the graph's capture of the registry.

Title: Safety and Efficacy of Gabapentin in Postherpetic Neuralgia
NCT number: NCT00636636
Status: Completed
Phases: Phase 3
Enrollment: 452 participants, actual
Lead sponsor: Depomed
Conditions: Neuralgia,Postherpetic
Interventions: Gabapentin Extended Release tablets, Placebo
First posted: 2008-03-14
Last updated: 2012-02-22
Results first posted: 2012-01-13

Source ClinicalTrials.gov

Registered outcomes5

Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.

List	Outcome	Time frame	Description
Primary	Mean Change in Baseline Observation Carried Forward (BOCF) Average Daily Pain Score	10 weeks	Average daily pain scored on 11-point numerical rating scale (where 0 = no pain, 10 = worst possible pain). Results presented as least squares (LS) mean change in baseline observation carried forward (BOCF) average daily pain score from baseline to the final week of efficacy treatment period (Week 10).
Secondary	Patient Global Impression of Change (PGIC)	10 weeks	Patient self-assessment of how much pain had changed at end of treatment period (Week 10) compared to pain at baseline; scored on 7-point numerical rating scale (where 1 = very much improved, 7 = very much worse). Results presented as number of participants categorized at end of treatment (Week 10) as "very much improved" (score = 1) or "much improved" (score = 2).
Secondary	Clinical Global Impression of Change (CGIC)	10 weeks	Investigator assessment of patient's overall PHN symptoms at end of treatment period (Week 10) compared to overall PHN symptoms at baseline; scored on 7-point numerical rating scale (where 1 = very much improved, 7 = very much worse). Results presented as number of participants categorized at end of treatment (Week 10) as "very much improved" (score = 1) or "much improved" (score = 2).
Secondary	Average Daily Sleep Interference Score	10 weeks	Assessed on 11-point numeric rating scale (where 0 = pain does not interfere with sleep, 10 = pain completely interferes with sleep); evaluated from daily sleep entry in electronic diary. Results presented as least squares (LS) mean change in baseline observation carried forward (BOCF) average daily sleep interference score from baseline to final week of treatment period (Week 10).
Other	Mean Change in Last Observation Carried Forward (LOCF) Average Daily Pain Score	10 weeks	Average daily pain scored on 11-point numerical rating scale (where 0 = no pain, 10 = worst possible pain). Results presented as least squares (LS) mean change in last observation carried forward (LOCF) average daily pain score from baseline to final week of efficacy treatment period (Week 10).

Source ClinicalTrials.gov

Outcomes5

Each outcome the trial posted results for, in ClinicalTrials.gov's words.

Type	Outcome	Time frame	Population	Units	Measured as
PRIMARY	Mean Change in Baseline Observation Carried Forward (BOCF) Average Daily Pain Score	10 weeks	ITT, BOCF	Scores on a scale	LEAST_SQUARES_MEAN
SECONDARY	Patient Global Impression of Change (PGIC)	10 weeks	ITT, BOCF	Participants	NUMBER
SECONDARY	Clinical Global Impression of Change (CGIC)	10 weeks		Participants	NUMBER
SECONDARY	Average Daily Sleep Interference Score	10 weeks		Scores on a scale	LEAST_SQUARES_MEAN
OTHER_PRE_SPECIFIED	Mean Change in Last Observation Carried Forward (LOCF) Average Daily Pain Score	10 weeks		Scores on a scale	LEAST_SQUARES_MEAN

Source ClinicalTrials.gov

Results by group10

Each measurement the trial posted, group by group, in the words and numbers it posted.

Outcome	Group	Value	Spread	Units
Mean Change in Baseline Observation Carried Forward (BOCF) Average Daily Pain Score	G-ER	-2.12	95% Confidence Interval 0.17	Scores on a scale
Mean Change in Baseline Observation Carried Forward (BOCF) Average Daily Pain Score	Placebo	-1.63	95% Confidence Interval 0.16	Scores on a scale
Patient Global Impression of Change (PGIC)	G-ER	94		Participants
Patient Global Impression of Change (PGIC)	Placebo	77		Participants
Clinical Global Impression of Change (CGIC)	G-ER	97		Participants
Clinical Global Impression of Change (CGIC)	Placebo	78		Participants
Average Daily Sleep Interference Score	G-ER	-2.30	Standard Error 0.16	Scores on a scale
Average Daily Sleep Interference Score	Placebo	-1.59	Standard Error 0.15	Scores on a scale
Mean Change in Last Observation Carried Forward (LOCF) Average Daily Pain Score	G-ER	-2.40	Standard Error 0.17	Scores on a scale
Mean Change in Last Observation Carried Forward (LOCF) Average Daily Pain Score	Placebo	-1.85	Standard Error 0.17	Scores on a scale

Source ClinicalTrials.gov

Participant flow10

How many started, completed or left each group, period by period.

Period	Milestone	Group	Participants
Overall Study	STARTED	G-ER	221
Overall Study	STARTED	Placebo	231
Overall Study	Safety & Efficacy of Gabapentin ER	G-ER	186
Overall Study	Safety & Efficacy of Gabapentin ER	Placebo	194
Overall Study	379	G-ER	186
Overall Study	379	Placebo	194
Overall Study	COMPLETED	G-ER	185
Overall Study	COMPLETED	Placebo	192
Overall Study	NOT COMPLETED	G-ER	36
Overall Study	NOT COMPLETED	Placebo	39

Source ClinicalTrials.gov

Adverse events52

Each adverse event the trial posted, group by group: the participants affected out of those at risk.

Type	Event	Organ system	Group	Affected	At risk	Events
other	Abdominal pain upper	Gastrointestinal disorders	G-ER	3	221	3
other	Abdominal pain upper	Gastrointestinal disorders	Placebo	6	231	6
other	Back pain	Musculoskeletal and connective tissue disorders	G-ER	2	221	2
other	Back pain	Musculoskeletal and connective tissue disorders	Placebo	3	231	3
other	Blood pressure increased	Investigations	G-ER	3	221	3
other	Blood pressure increased	Investigations	Placebo	2	231	2
other	Diarrhea	Gastrointestinal disorders	G-ER	6	221	6
other	Diarrhea	Gastrointestinal disorders	Placebo	5	231	5
other	Dizziness	Nervous system disorders	G-ER	25	221	25
other	Dizziness	Nervous system disorders	Placebo	4	231	4

1 to 10 of 52Source ClinicalTrials.gov

See all 52 adverse events

Adverse event totals6

The totals the trial posted for each group.

Total	Group	Affected	At risk
Total, all-cause mortality	G-ER
Total, all-cause mortality	Placebo
Total, other adverse events	G-ER	92	221
Total, other adverse events	Placebo	63	231
Total, serious adverse events	G-ER	4	221
Total, serious adverse events	Placebo	6	231

Source ClinicalTrials.gov

Papers1

The papers the trial lists on ClinicalTrials.gov.

PMID	Listed as
27037091	DERIVED

Source PubMed

Grants0

The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.

None in this release.

Trial comparisons3

Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.

Comparison	Source
G-ER vs Placebo: Patient Global Impression of Change (PGIC)	Trial comparisons
G-ER vs Placebo: Clinical Global Impression of Change (CGIC)	Trial comparisons
G-ER vs Placebo: serious adverse events	Trial comparisons

Tests0

The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.

None in this release.

Data dates

The day each source was copied for this release.

ClinicalTrials.gov: 2026-11-12; ClinicalTrials.gov
Results, from AACT: 2026-03-23; AACT
NIH grant links: 2026-11-13; NIH RePORTER

Sources 3

ClinicalTrials.gov's posted results, through CTTI's AACTFreely available. Acknowledgement requested
ClinicalTrials.govNo license stated
NIH RePORTER's clinical studies and project filesPublic domain

Each source's terms

ClinicalTrials.gov's posted results, through CTTI's AACTClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299
ClinicalTrials.govnone stated
NIH RePORTER's clinical studies and project filesPublic domain (NIH RePORTER)

ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.

For software

Read this trial from software.

The record and each of its lists are JSON, twenty rows a page. No key.

GET https://conductscience.org/api/trials/v1/NCT00636636

GET https://conductscience.org/api/trials/v1/NCT00636636/events?page=2

API reference For AI assistants