Trial Outcomes & Findings for A Study In Patients With Neuropathic Pain From Diabetic Peripheral Neuropathy (DPN) (NCT NCT00643760)

Last Updated: 2013-07-22

Results Overview

Baseline and EOMT values are the calculated means of the daily 24-hour API scores for each participant during the last 7 days prior to randomization (Baseline) and the earliest date of Week 13 visit/Withdrawal visit/last dose of study drug (EOMT). Participants used a hand-held diary to rate their API over the preceding 24 hours, using an 11-point Pain Intensity Numerical Rating Scale (PI-NRS) (0=no pain, 10=pain as bad as you can imagine). LOCF was used if less than 4 days of diary data were provided. Change from baseline was calculated as the EOMT score minus the Baseline score.

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

421 participants

Primary outcome timeframe

Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Results posted on

2013-07-22

Participant Flow

Participant milestones

Participant milestones
Measure	Placebo Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Overall Study STARTED	120	62	56	117	66
Overall Study Safety Population/Treated With Drug	120	62	56	116	66
Overall Study ITT Population	120	62	56	116	66
Overall Study COMPLETED	90	47	37	79	47
Overall Study NOT COMPLETED	30	15	19	38	19

Reasons for withdrawal

Reasons for withdrawal
Measure	Placebo Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Overall Study Adverse Event	11	5	12	21	6
Overall Study Lack of Efficacy	3	1	0	4	3
Overall Study Protocol Violation	7	6	4	4	6
Overall Study Lost to Follow-up	6	2	1	3	3
Overall Study Investigator Discretion	0	0	0	2	0
Overall Study Withdrawal by Subject	3	1	2	4	1

Baseline Characteristics

A Study In Patients With Neuropathic Pain From Diabetic Peripheral Neuropathy (DPN)

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Placebo n=120 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=62 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=56 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=116 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=66 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).	Total n=420 Participants Total of all reporting groups
Age Continuous	60.1 Years STANDARD_DEVIATION 10.63 • n=5 Participants	57.5 Years STANDARD_DEVIATION 10.32 • n=7 Participants	60.8 Years STANDARD_DEVIATION 8.97 • n=5 Participants	57.5 Years STANDARD_DEVIATION 9.87 • n=4 Participants	57.7 Years STANDARD_DEVIATION 10.59 • n=21 Participants	58.7 Years STANDARD_DEVIATION 10.20 • n=10 Participants
Sex: Female, Male Female	47 Participants n=5 Participants	28 Participants n=7 Participants	19 Participants n=5 Participants	45 Participants n=4 Participants	32 Participants n=21 Participants	171 Participants n=10 Participants
Sex: Female, Male Male	73 Participants n=5 Participants	34 Participants n=7 Participants	37 Participants n=5 Participants	71 Participants n=4 Participants	34 Participants n=21 Participants	249 Participants n=10 Participants
Race/Ethnicity, Customized African American/African Heritage	20 participants n=5 Participants	15 participants n=7 Participants	7 participants n=5 Participants	20 participants n=4 Participants	12 participants n=21 Participants	74 participants n=10 Participants
Race/Ethnicity, Customized American Indian or Alaskan Native	2 participants n=5 Participants	0 participants n=7 Participants	0 participants n=5 Participants	0 participants n=4 Participants	0 participants n=21 Participants	2 participants n=10 Participants
Race/Ethnicity, Customized Asian - Central/South Asian Heritage	0 participants n=5 Participants	0 participants n=7 Participants	0 participants n=5 Participants	1 participants n=4 Participants	0 participants n=21 Participants	1 participants n=10 Participants
Race/Ethnicity, Customized Asian - South East Asian Heritage	0 participants n=5 Participants	1 participants n=7 Participants	0 participants n=5 Participants	2 participants n=4 Participants	0 participants n=21 Participants	3 participants n=10 Participants
Race/Ethnicity, Customized White - Arabic/North African Heritage	0 participants n=5 Participants	2 participants n=7 Participants	2 participants n=5 Participants	1 participants n=4 Participants	0 participants n=21 Participants	5 participants n=10 Participants
Race/Ethnicity, Customized White - White/Caucasian/European Heritage	98 participants n=5 Participants	44 participants n=7 Participants	45 participants n=5 Participants	89 participants n=4 Participants	52 participants n=21 Participants	328 participants n=10 Participants
Race/Ethnicity, Customized Mixed Race	0 participants n=5 Participants	0 participants n=7 Participants	1 participants n=5 Participants	1 participants n=4 Participants	0 participants n=21 Participants	2 participants n=10 Participants
Race/Ethnicity, Customized Not Provided	0 participants n=5 Participants	0 participants n=7 Participants	1 participants n=5 Participants	2 participants n=4 Participants	2 participants n=21 Participants	5 participants n=10 Participants

PRIMARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population

Outcome measures

Outcome measures
Measure	Placebo n=120 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=62 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=56 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=116 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=66 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in the Mean 24-hour Average Pain Intensity (API) Score at End of Maintenance Treatment (EOMT) Using Last Observation Carried Forward (LOCF) Data	-2.08 scores on a scale Standard Error 0.196	-2.43 scores on a scale Standard Error 0.274	-2.10 scores on a scale Standard Error 0.289	-2.63 scores on a scale Standard Error 0.202	-1.65 scores on a scale Standard Error 0.266

SECONDARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population

Day-time is defined as the time between rising in the morning and going to bed at night. Participants recorded day-time API on a daily basis in the evening before bedtime using an 11-point PI-NRS (0=no pain, 10=pain as bad as you can imagine). Baseline and EOMT are as defined for the primary endpoint. Change from baseline was calculated as the EOMT score minus the baseline score. An ANCOVA model with baseline value, BMI, grouped center as covariates was used.

Outcome measures

Outcome measures
Measure	Placebo n=120 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=62 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=56 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=116 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=66 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in the Mean Day-time Average Pain Intensity (API) Score at EOMT Using LOCF Data	-2.07 scores on a scale Standard Error 0.195	-2.35 scores on a scale Standard Error 0.272	-2.06 scores on a scale Standard Error 0.286	-2.54 scores on a scale Standard Error 0.200	-1.50 scores on a scale Standard Error 0.264

SECONDARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population. There were two participants in the GEn 3600 mg/day group who did not complete enough post-baseline morning diaries to calculate an average night-time pain intensity score for the EOMT timepoint.

Night-time is defined as the time between going to bed at night and rising in the morning. Participants recorded night-time API on a daily basis in the morning upon awakening using an 11-point PI-NRS (0=no pain, 10=pain as bad as you can imagine). Baseline and EOMT are as defined for the primary endpoint. Change from baseline was calculated as the EOMT score minus the baseline score. An ANCOVA model with baseline value, BMI, grouped center as covariates was used.

Outcome measures

Outcome measures
Measure	Placebo n=120 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=62 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=56 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=114 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=66 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in the Mean Night-time Average Pain Intensity (API) Score at EOMT Using LOCF Data	-1.99 scores on a scale Standard Error 0.203	-2.15 scores on a scale Standard Error 0.282	-2.04 scores on a scale Standard Error 0.298	-2.71 scores on a scale Standard Error 0.210	-1.83 scores on a scale Standard Error 0.274

SECONDARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population. There were two participants in the GEn 3600 mg/day group who did not complete enough post-baseline morning diaries to calculate a current (morning) pain intensity score for the EOMT timepoint.

Current pain is defined as the participant's assessment of pain intensity "right now." Participants recorded their current morning pain intensity in the morning upon wakening using an 11-point PI-NRS (0=no pain, 10=pain as bad as you can imagine). Baseline and EOMT are as defined for the primary endpoint. Change from baseline was calculated as the EOMT score minus the baseline score. An ANCOVA model with baseline value, BMI, grouped center as covariates was used.

Outcome measures

Outcome measures
Measure	Placebo n=120 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=62 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=56 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=114 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=66 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in the Mean Current (Morning) Pain Intensity Score at EOMT Using LOCF Data	-1.90 scores on a scale Standard Error 0.192	-2.08 scores on a scale Standard Error 0.268	-1.95 scores on a scale Standard Error 0.282	-2.40 scores on a scale Standard Error 0.199	-1.50 scores on a scale Standard Error 0.260

SECONDARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population

Current pain is defined as the participant's assessment of pain intensity "right now." Participants recorded their current evening pain intensity in the evening before bedtime using an 11-point PI-NRS (0=no pain, 10=pain as bad as you can imagine). Baseline and EOMT are as defined for the primary endpoint. Change from baseline was calculated as the EOMT score minus the baseline score. An ANCOVA model with baseline value, BMI, grouped center as covariates was used.

Outcome measures

Outcome measures
Measure	Placebo n=120 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=62 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=56 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=116 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=66 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in the Mean Current (Evening) Pain Intensity Score at EOMT Using LOCF Data	-2.19 scores on a scale Standard Error 0.194	-2.24 scores on a scale Standard Error 0.271	-2.10 scores on a scale Standard Error 0.285	-2.66 scores on a scale Standard Error 0.200	-1.65 scores on a scale Standard Error 0.264

SECONDARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population

Day-time worst pain is defined as the partipant's assessment of their worst pain between rising in the morning and going to bed at night. Participants recorded day-time worst pain in the evening before bedtime using an 11-point PI-NRS (0=no pain, 10=pain as bad as you can imagine). Baseline and EOMT are as defined for the primary endpoint. Change from baseline was calculated as the EOMT score minus the baseline score. An ANCOVA model with baseline value, BMI, grouped center as covariates was used.

Outcome measures

Outcome measures
Measure	Placebo n=120 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=62 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=56 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=116 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=66 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in the Mean Day-time Worst Pain Intensity Score at EOMT Using LOCF Data	-2.33 scores on a scale Standard Error 0.210	-2.35 scores on a scale Standard Error 0.292	-2.25 scores on a scale Standard Error 0.307	-2.88 scores on a scale Standard Error 0.215	-1.62 scores on a scale Standard Error 0.284

SECONDARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population. There were two participants in the GEn 3600 mg/day group who did not complete enough post-baseline morning diaries to calculate a night-time worst pain intensity score for the EOMT timepoint.

Night-time worst pain is defined as the partipant's assessment of their worst pain between going to bed at night and rising in the morning. Participants recorded night-time worst pain in the morning upon awakening using an 11-point PI-NRS (0=no pain, 10=pain as bad as you can imagine). Baseline and EOMT are as defined for the primary endpoint. Change from baseline was calculated as the EOMT score minus the baseline score. An ANCOVA model with baseline value, BMI, grouped center as covariates was used.

Outcome measures

Outcome measures
Measure	Placebo n=120 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=62 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=56 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=114 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=66 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in the Mean Night-time Worst Pain Intensity Score at EOMT Using LOCF Data	-2.25 scores on a scale Standard Error 0.213	-2.24 scores on a scale Standard Error 0.297	-2.25 scores on a scale Standard Error 0.313	-3.00 scores on a scale Standard Error 0.221	-1.86 scores on a scale Standard Error 0.289

SECONDARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Participants assessed sleep interference due to pain on a daily basis in the morning upon awakening using an 11-point NRS (0=pain does not interfere with sleep, 10=pain completely interferes with sleep). Baseline and EOMT are as defined for the primary endpoint. Change from baseline was calculated as the EOMT score minus the baseline score. An ANCOVA model with baseline value, BMI, grouped center as covariates was used.

Outcome measures

Outcome measures
Measure	Placebo n=120 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=62 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=56 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=114 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=66 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in the Mean Sleep Interference Score at EOMT Using LOCF Data	-2.35 scores on a scale Standard Error 0.214	-2.54 scores on a scale Standard Error 0.298	-2.45 scores on a scale Standard Error 0.313	-3.01 scores on a scale Standard Error 0.221	-2.24 scores on a scale Standard Error 0.289

SECONDARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population

Mean daily use of rescue medication (milligrams of acetaminophen) was calculated by determining the average number of tablets taken per day of rescue medication (Commerical Tylenol) during treatment and multiplying that by 500 mg. Baseline and EOMT are as defined for the primary endpoint. Change from baseline was calculated as the EOMT score minus the baseline score. An ANCOVA model with baseline value, BMI, grouped center as covariates was used.

Outcome measures

Outcome measures
Measure	Placebo n=120 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=62 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=56 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=116 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=66 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in the Mean Daily Dose of Rescue Medication at EOMT Using LOCF Data	-261.99 milligrams Standard Error 73.630	-171.64 milligrams Standard Error 102.482	-102.51 milligrams Standard Error 107.918	-228.54 milligrams Standard Error 76.139	-246.07 milligrams Standard Error 99.758

SECONDARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population. Not all participants completed an NPS assessment at both Baseline and Week 13/Withdrawal; as such, the number analyzed is different from the full ITT Population counts.

The NPS assesses pain qualities and consists of 11-items, 10 assessed on an 11-point NRS (0=no impact to 10=greatest impact); and 1 open-ended question not used in score calculation. 4 summary scores are calculated: NPS 10 (items 1-7, 9-11), NPS 8 (8 pain descriptor items), NPS Non-Allodynic (NA) (8 NA items), and NPS 4 (4 pain quality items); and range from 0 to 100 (0=no impact and 100=greatest impact). The analysis is based on the change from baseline (BL) (EOMT score minus the BL score) using an ANCOVA model with BL value, BMI, grouped center as covariates.

Outcome measures

Outcome measures
Measure	Placebo n=112 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=58 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=45 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=108 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=62 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in Pain Quality as Assessed by the Neuropathic Pain Scale (NPS) Summary Scores at EOMT Using LOCF Data NPS 10 Score	-18.92 scores on a scale Standard Error 1.914	-18.43 scores on a scale Standard Error 2.658	-22.24 scores on a scale Standard Error 3.027	-25.49 scores on a scale Standard Error 1.970	-16.16 scores on a scale Standard Error 2.576
Change From Baseline in Pain Quality as Assessed by the Neuropathic Pain Scale (NPS) Summary Scores at EOMT Using LOCF Data NPS 4 Score	-20.54 scores on a scale Standard Error 2.120	-20.90 scores on a scale Standard Error 2.944	-25.15 scores on a scale Standard Error 3.352	-27.84 scores on a scale Standard Error 2.182	-16.06 scores on a scale Standard Error 2.853
Change From Baseline in Pain Quality as Assessed by the Neuropathic Pain Scale (NPS) Summary Scores at EOMT Using LOCF Data NPS 8 Score	-18.73 scores on a scale Standard Error 1.898	-17.83 scores on a scale Standard Error 2.637	-21.84 scores on a scale Standard Error 3.003	-25.14 scores on a scale Standard Error 1.954	-16.19 scores on a scale Standard Error 2.555
Change From Baseline in Pain Quality as Assessed by the Neuropathic Pain Scale (NPS) Summary Scores at EOMT Using LOCF Data NPS Non-Allodynic Score	-19.37 scores on a scale Standard Error 1.998	-18.89 scores on a scale Standard Error 2.776	-22.86 scores on a scale Standard Error 3.160	-26.35 scores on a scale Standard Error 2.057	-15.63 scores on a scale Standard Error 2.690

SECONDARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population. Not all participants completed an SF-MPQ assessment at both Baseline and Week 13/Withdrawal; as such, the number analyzed is different from the full ITT Population counts.

The SF-MPQ, a general pain instrument, assesses the characteristics and intensity of pain and consists of 15-items assessed on a 4-point scale (0=none, 1=mild, 2=moderate, and 3=severe). 3 summary scores are calculated: sensory score (sum of items 1-11, range 0-33), affective score (sum of items 12-15, range 0-12), total score (sum of items 1-15, range 0-45), where lower scores = lower pain/impact. Analysis is based on the change from baseline (BL) (EOMT score minus the BL score) using an ANCOVA model with BL value, BMI, grouped center as covariates.

Outcome measures

Outcome measures
Measure	Placebo n=112 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=57 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=44 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=108 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=62 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in Pain Characteristics and Intensity as Assessed by the Short Form-McGill Pain Questionnaire (SF-MPQ) at EOMT Using LOCF Data SF-MPQ Total Score	-5.85 scores on a scale Standard Error 0.865	-6.55 scores on a scale Standard Error 1.214	-6.75 scores on a scale Standard Error 1.381	-7.56 scores on a scale Standard Error 0.888	-4.01 scores on a scale Standard Error 1.161
Change From Baseline in Pain Characteristics and Intensity as Assessed by the Short Form-McGill Pain Questionnaire (SF-MPQ) at EOMT Using LOCF Data SF-MPQ Sensory Score	-4.25 scores on a scale Standard Error 0.674	-4.83 scores on a scale Standard Error 0.946	-5.31 scores on a scale Standard Error 1.077	-5.50 scores on a scale Standard Error 0.692	-2.73 scores on a scale Standard Error 0.906
Change From Baseline in Pain Characteristics and Intensity as Assessed by the Short Form-McGill Pain Questionnaire (SF-MPQ) at EOMT Using LOCF Data SF-MPQ Affective Score	-1.63 scores on a scale Standard Error 0.247	-1.65 scores on a scale Standard Error 0.348	-1.45 scores on a scale Standard Error 0.395	-2.07 scores on a scale Standard Error 0.254	-1.26 scores on a scale Standard Error 0.332

SECONDARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population. Not all participants completed a 50-foot walk at both Baseline and Week 13/Withdrawal; as such, the number analyzed is different from the full ITT Population counts.

Baseline and EOMT scores are the pain scores each participant reported after taking a 50-foot walk at the randomization and Week 13/Withdrawal visits, respectively, using an 11-point PI-NRS (0=no pain, 10=pain as bad as you can imagine). Change from baseline was calculated as the EOMT score minus the baseline score. An ANCOVA model with BMI, baseline pain intensity after 50-foot walk, pain intensity prior to 50-foot walk at the visit being assessed, and grouped center as covariates was used.

Outcome measures

Outcome measures
Measure	Placebo n=111 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=57 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=44 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=107 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=59 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in Pain Score After Taking a 50-foot Walk at EOMT	-2.38 scores on a scale Standard Error 0.077	-2.32 scores on a scale Standard Error 0.107	-2.36 scores on a scale Standard Error 0.122	-2.52 scores on a scale Standard Error 0.080	-2.17 scores on a scale Standard Error 0.106

SECONDARY outcome

Timeframe: EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population. Not all participants completed a PGIC assessment at Week 13/Withdrawal; as such, the number analyzed is different from the full ITT Population counts.

The PGIC is a single-item questionnaire designed to provide an overall assessment of treatment from the participant's perspective since the start of the study. It is measured on a 7-point scale, where 1=very much improved and 7=very much worse. A participant is considered a responder if they have a response of "very much improved" or "much improved." EOMT response is defined as the score recorded at the Week 13/Withdrawal visit.

Outcome measures

Outcome measures
Measure	Placebo n=112 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=58 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=46 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=108 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=62 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Number of Participants Who Are Responders on the Patient Global Impression of Change (PGIC) Questionnaire at EOMT Using LOCF Data	46 participants	22 participants	24 participants	53 participants	62 participants

SECONDARY outcome

Timeframe: EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population. Not all participants had a CGIC assessment at Week 13/Withdrawal; as such, the number analyzed is different from the full ITT Population counts.

The CGIC is a single-item questionnaire designed to provide an overall assessment of treatment from the clinician's perspective since the start of the study. It is measured on a 7-point scale, where 1=very much improved and 7=very much worse. A participant is considered a responder if they have a response of "very much improved" or "much improved." EOMT response is defined as the score recorded at the Week 13/Withdrawal visit.

Outcome measures

Outcome measures
Measure	Placebo n=98 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=52 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=40 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=89 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=54 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Number of Participants Who Are Responders on the Clinician Global Impression of Change (CGIC) Questionnaire at EOMT Using LOCF Data	39 participants	20 participants	22 participants	50 participants	17 participants

SECONDARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population

Baseline and EOMT scores are the calculated means of the 24-hour average pain scores for each participant during the last 7 days prior to randomization and EOMT, respectively. Percent reduction from baseline was calculated as the \[(EOMT score minus the baseline score)divided by the baseline score\], multiplied by 100. The PI-NRS is an 11-point scale (0=no pain, 10=pain as bad as you can imagine) by which a participant assesses their 24-hour average pain intensity.

Outcome measures

Outcome measures
Measure	Placebo n=120 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=62 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=56 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=116 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=66 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Number of Participants Achieving Various Levels of Percent Reduction From Baseline in the Mean 24-hour Average Pain Intensity Score at EOMT Using LOCF Data >= 30% reduction from baseline	57 participants	31 participants	25 participants	66 participants	28 participants
Number of Participants Achieving Various Levels of Percent Reduction From Baseline in the Mean 24-hour Average Pain Intensity Score at EOMT Using LOCF Data >= 60% reduction from baseline	26 participants	21 participants	11 participants	41 participants	9 participants
Number of Participants Achieving Various Levels of Percent Reduction From Baseline in the Mean 24-hour Average Pain Intensity Score at EOMT Using LOCF Data >= 70% reduction from baseline	15 participants	17 participants	6 participants	25 participants	5 participants
Number of Participants Achieving Various Levels of Percent Reduction From Baseline in the Mean 24-hour Average Pain Intensity Score at EOMT Using LOCF Data >= 90% reduction from baseline	4 participants	5 participants	2 participants	8 participants	3 participants
Number of Participants Achieving Various Levels of Percent Reduction From Baseline in the Mean 24-hour Average Pain Intensity Score at EOMT Using LOCF Data >= 0% reduction from baseline	103 participants	55 participants	50 participants	101 participants	55 participants
Number of Participants Achieving Various Levels of Percent Reduction From Baseline in the Mean 24-hour Average Pain Intensity Score at EOMT Using LOCF Data >= 10% reduction from baseline	86 participants	43 participants	42 participants	91 participants	42 participants
Number of Participants Achieving Various Levels of Percent Reduction From Baseline in the Mean 24-hour Average Pain Intensity Score at EOMT Using LOCF Data >= 20% reduction from baseline	73 participants	36 participants	34 participants	78 participants	36 participants
Number of Participants Achieving Various Levels of Percent Reduction From Baseline in the Mean 24-hour Average Pain Intensity Score at EOMT Using LOCF Data >= 40% reduction from baseline	46 participants	28 participants	19 participants	55 participants	20 participants
Number of Participants Achieving Various Levels of Percent Reduction From Baseline in the Mean 24-hour Average Pain Intensity Score at EOMT Using LOCF Data >= 50% reduction from baseline	35 participants	26 participants	15 participants	46 participants	14 participants
Number of Participants Achieving Various Levels of Percent Reduction From Baseline in the Mean 24-hour Average Pain Intensity Score at EOMT Using LOCF Data >= 80% reduction from baseline	11 participants	11 participants	5 participants	17 participants	4 participants
Number of Participants Achieving Various Levels of Percent Reduction From Baseline in the Mean 24-hour Average Pain Intensity Score at EOMT Using LOCF Data 100% reduction from baseline	3 participants	4 participants	1 participants	5 participants	3 participants

SECONDARY outcome

Timeframe: Any time post-baseline until date of last dose of study medication (up to Week 13)

Population: ITT Population

Sustained improvement in the 24-hour average pain intensity score is defined as at least 2 consecutive days on which the 24-hour average pain intensity score is \>=2 points less than the mean 24-hour average pain intensity score at baseline. Time to onset is measured from baseline and was calculated as first day of event minus last day of baseline and is expressed in days. Baseline score is the calculated mean of the 24-hour average pain score for each participant during the last 7 days prior to randomization.

Outcome measures

Outcome measures
Measure	Placebo n=120 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=62 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=56 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=116 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=66 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Time to Onset of Sustained Improvement in the 24-hour Average Pain Intensity Score	24 days Interval 2.0 to 97.0	25 days Interval 2.0 to 76.0	22 days Interval 2.0 to 62.0	15 days Interval 1.0 to 87.0	29 days Interval 2.0 to 93.0

SECONDARY outcome

Timeframe: Baseline and EOMT

Population: ITT Population. Not all participants completed a BPI assessment at both Baseline and Week 13/Withdrawal; as such, the number analyzed is different from the full ITT Population counts.

The BPI, a general pain instrument, assesses the severity and interference of pain; and consists of 6 items assessed on an 11-point NRS (0=no impact and 10=greatest impact). 2 summary scores are calculated: BPI Severity Score (average of first 4 items) and BPI Interference Score (average of 7 responses to item 6); where each summary score ranges from 0 to 10 (0=no impact and 10=greatest impact). Analysis of this endpoint is based on the change from baseline (BL) (EOMT score minus the BL score) using an ANCOVA model with BL value, BMI, grouped center as covariates.

Outcome measures

Outcome measures
Measure	Placebo n=112 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=57 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=44 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=107 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=62 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in Severity of Pain and the Impact of Pain as Assessed by the Brief Pain Inventory (BPI) at EOMT Using LOCF Data Brief Pain Inventory Severity of Pain	-2.1 scores on a scale Standard Error 0.21	-2.3 scores on a scale Standard Error 0.29	-2.4 scores on a scale Standard Error 0.33	-2.8 scores on a scale Standard Error 0.21	-1.7 scores on a scale Standard Error 0.28
Change From Baseline in Severity of Pain and the Impact of Pain as Assessed by the Brief Pain Inventory (BPI) at EOMT Using LOCF Data Brief Pain Inventory Interference of Pain	-2.0 scores on a scale Standard Error 0.21	-2.0 scores on a scale Standard Error 0.30	-2.1 scores on a scale Standard Error 0.34	-2.5 scores on a scale Standard Error 0.22	-1.9 scores on a scale Standard Error 0.29

SECONDARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population. Not all participants completed an SF-36 at both Baseline and Week 13/Withdrawal; as such, the number analyzed is different from the full ITT Population counts.

The SF-36 is a general health-related quality of life instrument consisting of 36 items with various response options (Yes/No, 5- to 6-point Likert scale). Summary scores are calculated for 8 domains and 2 components (physical and mental); where scores range from 0 to 100 (higher scores = better quality of life). Analysis of this endpoint is based on the change from baseline (BL) (EOMT score minus the BL score) using an ANCOVA model with BL value, BMI, grouped center as covariates.

Outcome measures

Outcome measures
Measure	Placebo n=112 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=57 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=44 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=107 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=61 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in Quality of Life as Assessed by the 36-Item Short Form Health Survey (SF-36) at EOMT Using LOCF Data SF-36 Mental Component Summary Score	2.5 scores on a scale Standard Error 0.88	0.4 scores on a scale Standard Error 1.24	1.5 scores on a scale Standard Error 1.41	1.6 scores on a scale Standard Error 0.91	0.7 scores on a scale Standard Error 1.20
Change From Baseline in Quality of Life as Assessed by the 36-Item Short Form Health Survey (SF-36) at EOMT Using LOCF Data SF-36 Physical Component Summary Score	3.1 scores on a scale Standard Error 0.67	3.5 scores on a scale Standard Error 0.93	3.7 scores on a scale Standard Error 1.06	4.6 scores on a scale Standard Error 0.69	3.7 scores on a scale Standard Error 0.90

SECONDARY outcome

Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)

Population: ITT Population. Not all participants completed a POMS-B at both Baseline and Week 13/Withdrawal; as such, the number analyzed is different from the full ITT Population counts.

The POMS-B, an emotional functioning instrument, assesses mood, tension, and other psychological symptoms and consists of 30-items assessed on a 5-point scale (0=not at all to 4=extremely). 6 summary scores are calculated: Tension/Anxiety, Depression/Rejection, Anger/Hostility, Vigor/Activity, Fatigue/Inertia, and Confusion/Bewilderment; and range from 0-20 (higher scores = more negative mood state). Analysis of this endpoint is based on the change from baseline (BL) (EOMT score minus the BL score) using an ANCOVA model with BL value, BMI, grouped center as covariates.

Outcome measures

Outcome measures
Measure	Placebo n=112 Participants Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=57 Participants One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=44 Participants Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=107 Participants Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=61 Participants Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Change From Baseline in Emotional Functioning as Assessed by the Profile of Mood States-Brief Form (POMS-B) at EOMT Using LOCF Data Tension/Anxiety Domain Score	-1.0 scores on a scale Standard Error 0.29	-0.6 scores on a scale Standard Error 0.41	-0.7 scores on a scale Standard Error 0.47	-0.9 scores on a scale Standard Error 0.30	-0.3 scores on a scale Standard Error 0.40
Change From Baseline in Emotional Functioning as Assessed by the Profile of Mood States-Brief Form (POMS-B) at EOMT Using LOCF Data Anger/Hostility Domain Score	-0.5 scores on a scale Standard Error 0.32	-0.8 scores on a scale Standard Error 0.45	-0.5 scores on a scale Standard Error 0.51	-0.3 scores on a scale Standard Error 0.33	-0.3 scores on a scale Standard Error 0.44
Change From Baseline in Emotional Functioning as Assessed by the Profile of Mood States-Brief Form (POMS-B) at EOMT Using LOCF Data Vigor/Activity Domain Score	0.6 scores on a scale Standard Error 0.32	-0.1 scores on a scale Standard Error 0.45	0.1 scores on a scale Standard Error 0.51	0.7 scores on a scale Standard Error 0.33	-0.4 scores on a scale Standard Error 0.44
Change From Baseline in Emotional Functioning as Assessed by the Profile of Mood States-Brief Form (POMS-B) at EOMT Using LOCF Data Fatigue/Inertia Domain Score	-0.8 scores on a scale Standard Error 0.37	-0.5 scores on a scale Standard Error 0.52	-1.1 scores on a scale Standard Error 0.59	-1.1 scores on a scale Standard Error 0.38	-0.1 scores on a scale Standard Error 0.50
Change From Baseline in Emotional Functioning as Assessed by the Profile of Mood States-Brief Form (POMS-B) at EOMT Using LOCF Data Confusion/Bewilderment Domain Score	-0.3 scores on a scale Standard Error 0.21	0.2 scores on a scale Standard Error 0.29	-0.1 scores on a scale Standard Error 0.33	0.0 scores on a scale Standard Error 0.22	-0.2 scores on a scale Standard Error 0.28
Change From Baseline in Emotional Functioning as Assessed by the Profile of Mood States-Brief Form (POMS-B) at EOMT Using LOCF Data Depression/Rejection Domain Score	-0.5 scores on a scale Standard Error 0.30	-0.2 scores on a scale Standard Error 0.43	-0.6 scores on a scale Standard Error 0.49	-0.3 scores on a scale Standard Error 0.32	0.4 scores on a scale Standard Error 0.41

Adverse Events

Placebo

Serious events: 6 serious events

Other events: 50 other events

Deaths: 0 deaths

GEn 1200 mg/Day

Serious events: 3 serious events

Other events: 34 other events

Deaths: 0 deaths

GEn 2400 mg/Day

Serious events: 4 serious events

Other events: 25 other events

Deaths: 0 deaths

GEn 3600 mg/Day

Serious events: 5 serious events

Other events: 62 other events

Deaths: 0 deaths

PGB 300 mg/Day

Serious events: 2 serious events

Other events: 32 other events

Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure	Placebo n=120 participants at risk Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=62 participants at risk One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=56 participants at risk Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=116 participants at risk Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=66 participants at risk Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Metabolism and nutrition disorders Hyperkalaemia	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.8% 1/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Metabolism and nutrition disorders Hypoglycaemia	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.86% 1/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
General disorders Chest pain	0.83% 1/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
General disorders Oedema peripheral	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.86% 1/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Infections and infestations Cellulitis	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.6% 1/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Infections and infestations Infected skin ulcer	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.6% 1/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Hepatobiliary disorders Cholecystitis	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.5% 1/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Injury, poisoning and procedural complications Ankle fracture	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.8% 1/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Musculoskeletal and connective tissue disorders Rhabdomyolysis	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.86% 1/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Neoplasms benign, malignant and unspecified (incl cysts and polyps) Chronic lymphocytic leukaemia	0.83% 1/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Psychiatric disorders Affective disorder	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.5% 1/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Renal and urinary disorders Renal failure	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.8% 1/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Reproductive system and breast disorders Benign prostatic hyperplasia	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.6% 1/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Respiratory, thoracic and mediastinal disorders Respiratory failure	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.8% 1/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Skin and subcutaneous tissue disorders Skin ulcer	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.6% 1/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Cardiac disorders Angina pectoris	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.86% 1/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Cardiac disorders Coronary artery stenosis	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.86% 1/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Cardiac disorders Sinus tachycardia	0.83% 1/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Cardiac disorders Supraventricular tachycardia	0.83% 1/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Nervous system disorders Ataxia	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.86% 1/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Nervous system disorders Dizziness	0.83% 1/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Nervous system disorders Partial seizures	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.8% 1/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Nervous system disorders Syncope	0.83% 1/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Metabolism and nutrition disorders Diabetic ketoacidosis	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.8% 1/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.

Other adverse events

Other adverse events
Measure	Placebo n=120 participants at risk Three 600 milligram (mg) gabapentin enacarbil (XP13512/GSK1838262), hereafter referred to as GEn, placebo tablets taken orally twice daily (morning and evening); one 100 mg pregabalin (PGB) placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 1200 mg/Day n=62 participants at risk One 600 mg extended release (ER) GEn tablet and two 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 2400 mg/Day n=56 participants at risk Two 600 mg ER GEn tablets and one 600 mg GEn placebo tablet taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	GEn 3600 mg/Day n=116 participants at risk Three 600 mg ER GEn tablets taken orally twice daily (morning and evening); one 100 mg PGB placebo capsule taken orally three times daily (morning, midday, and evening).	PGB 300 mg/Day n=66 participants at risk Three 600 mg GEn placebo tablets taken orally twice daily (morning and evening); one 100 mg PGB capsule taken orally three times daily (morning, midday, and evening).
Nervous system disorders Headache	7.5% 9/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.8% 3/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	7.1% 4/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	3.4% 4/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	9.1% 6/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Musculoskeletal and connective tissue disorders Muscle spasms	3.3% 4/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	9.7% 6/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	9.5% 11/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.5% 3/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Gastrointestinal disorders Diarrhoea	5.0% 6/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.8% 3/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	3.6% 2/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	5.2% 6/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	7.6% 5/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Infections and infestations Urinary tract infection	4.2% 5/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.8% 3/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	7.1% 4/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	5.2% 6/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	6.1% 4/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Nervous system disorders Dizziness	5.0% 6/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	14.5% 9/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	14.3% 8/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	13.8% 16/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	13.6% 9/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Nervous system disorders Somnolence	4.2% 5/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	3.2% 2/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	12.5% 7/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	12.1% 14/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	13.6% 9/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Gastrointestinal disorders Nausea	7.5% 9/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	11.3% 7/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	7.1% 4/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	6.0% 7/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.5% 3/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
General disorders Oedema peripheral	4.2% 5/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	3.2% 2/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	8.6% 10/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	16.7% 11/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Gastrointestinal disorders Constipation	3.3% 4/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.8% 3/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	7.1% 4/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	3.4% 4/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	9.1% 6/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
General disorders Fatigue	2.5% 3/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.8% 3/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	5.4% 3/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.3% 5/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	6.1% 4/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Musculoskeletal and connective tissue disorders Arthralgia	4.2% 5/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.6% 1/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	3.6% 2/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.3% 5/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.5% 3/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Infections and infestations Nasopharyngitis	4.2% 5/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.6% 1/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	3.6% 2/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	3.4% 4/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.5% 3/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Musculoskeletal and connective tissue disorders Pain in extremity	1.7% 2/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.6% 1/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	7.1% 4/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	5.2% 6/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	3.0% 2/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Eye disorders Vision blurred	4.2% 5/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	5.4% 3/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.7% 2/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.5% 3/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Investigations Weight increased	0.83% 1/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	3.6% 2/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.3% 5/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	7.6% 5/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Musculoskeletal and connective tissue disorders Back pain	2.5% 3/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.6% 1/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.8% 1/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	2.6% 3/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.5% 3/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Metabolism and nutrition disorders Increased appetite	3.3% 4/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	5.4% 3/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.86% 1/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.5% 3/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Gastrointestinal disorders Dry mouth	3.3% 4/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	7.1% 4/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.86% 1/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.5% 1/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Nervous system disorders Disturbance in attention	1.7% 2/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	3.2% 2/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.7% 2/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.5% 3/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Gastrointestinal disorders Vomiting	2.5% 3/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.8% 3/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.8% 1/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.7% 2/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Infections and infestations Bronchitis	0.83% 1/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.8% 3/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.8% 1/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.86% 1/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.5% 1/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Injury, poisoning and procedural complications Excoriation	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.6% 1/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.8% 1/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.86% 1/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.5% 3/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Nervous system disorders Hypoaesthesia	0.83% 1/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.6% 1/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.8% 1/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.5% 3/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Nervous system disorders Paraesthesia	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	3.2% 2/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.8% 1/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.5% 3/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.
Injury, poisoning and procedural complications Fall	0.00% 0/120 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	4.8% 3/62 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	1.8% 1/56 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.86% 1/116 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.	0.00% 0/66 Adverse events (AEs) and serious adverse events (SAEs) were captured for all participants in the Safety Population, comprised of all randomized participants who took at least one dose of investigational product.

Additional Information

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Principal investigator is a sponsor employee GSK agreements may vary with individual investigators, but will not prohibit any investigator from publishing. GSK supports the publication of results from all centers of a multi-center trial but requests that reports based on single-site data not precede the primary publication of the entire clinical trial.
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