Effect Of Pregabalin Treatment In Patients With Diabetic Nerve Pain Who Currently Use A Non-Steroid Anti-Inflammatory Drug (NSAID) For Another Pain

• ClinicalTrials.gov Identifier: NCT01455415
• Recruitment Status: Completed
• First Posted: October 20, 2011
• Results First Posted: April 23, 2015
• Last Update Posted: April 23, 2015
• Sponsor: Pfizer
• Information provided by (Responsible Party): Pfizer

• Study Type: Interventional
• Study Design: Allocation: Randomized; Intervention Model: Crossover Assignment; Masking: Double (Participant, Investigator); Primary Purpose: Treatment
• Condition: Painful Diabetic Peripheral Neuropathy
• Interventions: Drug: pregabalin; Drug: placebo
• Enrollment: 306

Participant Flow

Recruitment Details	501 participants were screened, of whom 197 were withdrawn before randomization. 304 were randomized, of whom 3 discontinued before being treated. Participants were randomized at 47 centers in 3 countries: US (43), Czech Republic (3), and Italy (1). 4 centers received study drug but did not randomize participants.
Pre-assignment Details	Participants completed daily pain and sleep diary from Visit 1 (Screening) to Visit 9. Participants with a mean pain score ≥ 4 (moderate to severe pain) and those having completed ≥ 4 daily pain dairies over past 7 days and having a mean score of ≥ 4 at Visit 2 (Baseline) were randomized.

Arm/Group Title	Pregabalin/Placebo	Placebo/Pregablin
Arm/Group Description	Participants were randomized to double-blind treatment with pregabalin for 6 weeks (150 - 300 mg/day) in period 1 followed by placebo in period 2. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	Participants were randomized to double-blind treatment with placebo for 6 weeks in period 1 followed by pregabalin in period 2 (150 - 300 mg/day). There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Period Title: Period 1
Started	154 [1]	147 [1]
Completed	135	123
Not Completed	19	24
Reason Not Completed
Adverse Event (AE) Related to Study Drug	9	6
Lost To Follow-up Related to Study Drug	3	3
Drug Error not Associated to AE	0	1
AE Not Related to Study Drug	2	6
Withdrawal by Subject	4	5
Unspecified Reason	1	1
Protocol Violation	0	2
[1] Started=Treated
Period Title: Washout
Started	135	123
Completed	127	116
Not Completed	8	7
Reason Not Completed
AE Related to Study Drug	2	0
Lost to Follow-up	1	0
Drug Error not Associated to AE	2	1
AE Not Related to Study Drug	2	3
Unspecified Reason	1	2
Protocol Violation	0	1
Period Title: Period 2
Started	127	116
Completed	114	106
Not Completed	13	10
Reason Not Completed
AE Related to Study Drug	1	2
Lost to Follow-up	2	1
AE Not Related to Study Drug	2	1
Lack of Efficacy	2	0
Withdrawal by Subject	2	3
Unspecified Reason	2	3
Protocol Violation	2	0
Period Title: Follow-up
Started	114	106
Completed	111	104
Not Completed	3	2
Reason Not Completed
AE Related to Study Drug	0	1
Lack of Efficacy	0	1
Withdrawal by Subject	2	0
Unspecified Reason	1	0

Baseline Characteristics

Arm/Group Title		Pregabalin/Placebo	Placebo/Pregablin	Total
Arm/Group Description		Participants were randomized to double-blind treatment with pregabalin for 6 weeks (150 - 300 mg/day) in period 1 followed by placebo in period 2. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	Participants were randomized to double-blind treatment with placebo for 6 weeks in period 1 followed by pregabalin in period 2 (150 - 300 mg/day). There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	Total of all reporting groups
Overall Number of Baseline Participants		154	147	301
Baseline Analysis Population Description		Intent-to-Treat Population (ITT) included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.
Age, Continuous; Mean (Standard Deviation); Unit of measure: Years
	Number Analyzed	154 participants	147 participants	301 participants
		59.4 (9.8)	58.4 (9.5)	58.9 (9.7)
Sex: Female, Male; Measure Type: Count of Participants; Unit of measure: Participants
	Number Analyzed	154 participants	147 participants	301 participants
	Female	65 42.2%	72 49.0%	137 45.5%
	Male	89 57.8%	75 51.0%	164 54.5%

Outcome Measures

1. Primary Outcome

Title	Average Diabetic Peripheral Neuropathy (DPN) Pain Based on a Numeric Rating Scale (NRS) Over the Last 7 Days of Each Treatment Period (Week 6 of Each Treatment Period)
Description	The daily pain diary consisted of an 11-point numeric scale ranging from 0 ("no pain") to 10 ("worst possible pain"). Participants described their pain during the past 24 hours by having chosen the appropriate number between 0 and 10. Self assessment was performed daily in the evening before bedtime on a telephone via interactive voice recognition system (IVRS) (time window for completion between 6.00 pm to midnight). The endpoint mean pain score was defined as the mean of the last 7 daily diary pain ratings while taking study drug in each treatment period - period 1 and period 2, respectively. A rating of 1 - 3 was considered as mild pain; 4 - 6 as moderate pain; and 7 - 10 as severe pain.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	4.980 (0.127)	5.018 (0.126)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	A longitudinal analysis was done using a repeated measure linear mixed effects model including visit, treatment, an indicator variable for Week 6, and treatment by visit and by the indicator variable interaction as fixed effect factors and participant within sequence and within-participant error (estimated by using an unstructured covariance structure) as random factors. The treatment differences were tested using within-participant variability as the error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.7174
	Comments	Primary analysis was two-sided and performed at the 0.05 significance level.
	Method	Repeated measure mixed effects model
	Comments	The Kenward-Roger method was used to estimate denominator degrees of freedom.
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.038
	Confidence Interval	(2-Sided) 95%; -0.248 to 0.171
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.106
	Estimation Comments	[Not Specified]

2. Secondary Outcome

Title	Percentage of Participants Achieving 30% Reduction in Mean DPN Pain Score From Baseline at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	Daily pain diary consisted of an 11-point numeric scale ranging from 0 ("no pain") to 10 ("worst possible pain"). Participants described their pain during the past 24 hours by having chosen the appropriate number between 0 and 10. Self assessment was performed daily in the evening before bedtime on a telephone via IVRS (time window for completion between 6.00 pm to midnight). The endpoint mean pain score was defined as the mean of the last 7 daily diary pain ratings while taking study drug in each treatment period - period 1 and period 2, respectively. A rating of 1 - 3 was considered as mild pain; 4 - 6 as moderate pain; and 7 - 10 as severe pain.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Measure Type: Number; Unit of Measure: percentage of participants
	34.56	31.16

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a logistic regression model which included baseline pain, sequence, period and treatment as covariate.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.3287
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Regression, Logistic
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Odds Ratio (OR)
	Estimated Value	1.20
	Confidence Interval	(2-Sided) 95%; 0.83 to 1.73
	Estimation Comments	[Not Specified]

3. Secondary Outcome

Title	Percentage of Participants Achieving 50% Reduction in Mean DPN Pain Score From Baseline at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	Daily pain diary consisted of an 11-point numeric scale ranging from 0 ("no pain") to 10 ("worst possible pain"). Participants described their pain during the past 24 hours by having chosen the appropriate number between 0 and 10. Self assessment was performed daily in the evening before bedtime on a telephone via IVRS (time window for completion between 6.00 pm to midnight). The endpoint mean pain score was defined as the mean of the last 7 daily diary pain ratings while taking study drug in each treatment period - period 1 and period 2, respectively. A rating of 1 - 3 was considered as mild pain; 4 - 6 as moderate pain; and 7 - 10 as severe pain.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Measure Type: Number; Unit of Measure: percentage of participants
	20.22	15.58

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a logistic regression model which included baseline pain, sequence, period and treatment as covariate.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.0625
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Regression, Logistic
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Odds Ratio (OR)
	Estimated Value	1.57
	Confidence Interval	(2-Sided) 95%; 0.98 to 2.51
	Estimation Comments	[Not Specified]

4. Secondary Outcome

Title	Brief Pain Inventory-Short Form (BPI-sf) Score for Pain-Severity Domain at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	The BPI-sf is a self-administered questionnaire developed to assess the severity of pain and the impact of pain on daily functions during a 24 hour period prior to evaluation. Four items measure pain (0: no pain; 10: worst pain possible) at its "worst, "least", "average", and "now" (current pain) on an 11-point scale. Scores range from 0 - 10 with higher scores indicating greater pain severity.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	4.49 (0.11)	4.48 (0.11)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline pain severity, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.9448
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	0.01
	Confidence Interval	(2-Sided) 95%; -0.21 to 0.22
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.11
	Estimation Comments	[Not Specified]

5. Secondary Outcome

Title	BPI-sf Score for Pain-Interference Domain at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	The BPI-sf is a self-administered questionnaire developed to assess the severity of pain and the impact of pain on daily functions during a 24 hour period prior to evaluation. Seven sub-questions evaluates the level of interference of pain on daily functioning (general activity, walking, work ability, mood, enjoyment of life, relations with other people, and sleep) on an 11-point scale (0: does not interfere; 10: completely interferes). Scores range from 0 - 10 with higher scores indicating greater interference.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	3.50 (0.12)	3.59 (0.11)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline interference score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.4548
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.09
	Confidence Interval	(2-Sided) 95%; -0.32 to 0.14
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.12
	Estimation Comments	[Not Specified]

6. Secondary Outcome

Title	Mean Sleep Interference Rating Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	The daily sleep diary consists of an 11-point numeric rating scale with which the participant rates how painful DPN pain has interfered with their sleep during the past 24 hours. Zero indicates "does not interfere with sleep" and 10 indicates "completely interferes (unable to sleep due to pain)". Self assessment was performed daily in the evening before bedtime on a telephone via IVRS (time window for completion between 6.00 pm to midnight) after completion of the daily pain diary.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	4.11 (0.12)	4.35 (0.12)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using linear mixed effects model including baseline score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.0272
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.24
	Confidence Interval	(2-Sided) 95%; -0.44 to -0.03
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.11
	Estimation Comments	[Not Specified]

7. Secondary Outcome

Title	Hospital Anxiety and Depression Scale - Anxiety (HADS-A) Total Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	The Hospital Anxiety and Depression Scale (HADS) is a 14- item self-administered questionnaire that consists of 2 scales, one measuring anxiety (HADS-A), and the other measuring depression (HADS-D). Each subscale consists of 7 statements and the participant responds as to how each item applies to him/her over the past week on 4- point response scale. Separate scores are calculated for anxiety and depression and a score (ranging from 0 to 21) is obtained for each subscale. The higher the score, the more severe the anxiety or depression.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	4.90 (0.18)	4.96 (0.18)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline HADS-A score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.7344
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.06
	Confidence Interval	(2-Sided) 95%; -0.42 to 0.30
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.18
	Estimation Comments	[Not Specified]

8. Secondary Outcome

Title	HADS-D Total Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	HADS is a 14- item self-administered questionnaire that consists of 2 scales, one measuring anxiety (HADS-A), and the other measuring depression (HADS-D). Each subscale consists of 7 statements and the participant responds as to how each item applies to him/her over the past week on 4- point response scale. Separate scores are calculated for anxiety and depression and a score (ranging from 0 to 21) is obtained for each subscale. The higher the score, the more severe the anxiety or depression.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	4.42 (0.17)	4.50 (0.17)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline HADS-D score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.6007
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.09
	Confidence Interval	(2-Sided) 95%; -0.42 to 0.24
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.17
	Estimation Comments	[Not Specified]

9. Secondary Outcome

Title	Norfolk Quality of Life-Diabetic Neuropathy (Norfolk QOL-DN) Total Quality of Life (TQOL) Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	Norfolk QOL-DN is a 35-item participant-rated questionnaire used to assess impact of diabetic neuropathy on quality of life of participants with diabetic neuropathy. All symptoms (1 - 7) are scored as either 1 or 0, indicating presence or absence of the symptom. With exception of questions 31 and 32, the other items are scored according to the 5-point Likert Scale (0 - 4, "no problem" to "severe problem"). In question 31, "good", the middle item, is scored as 0, "very good" as -1, "excellent" as -2, "fair" as 1, and "poor" as 2. In question 32, "about the same", the middle item, is scored as 0, "somewhat better" as -1, "much better" as -2, "somewhat worse" as 1, and "much worse" as 2. TQOL score should be summed as follow: sum (Σ) (1 - 7, 8 - 35). The (sub)scales are calculated without weighting of any kind, and reported as the integer sum of listed questionnaire items (range: -4 - 136). The QOL-DN version that was administered in this study was modified with a 2-week recall period.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	37.22 (1.03)	38.30 (1.02)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline total score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.2987
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-1.08
	Confidence Interval	(2-Sided) 95%; -3.13 to 0.96
	Parameter Dispersion	Type: Standard Error of the mean; Value: 1.04
	Estimation Comments	[Not Specified]

10. Secondary Outcome

Title	Norfolk QOL-DN Symptoms Domain Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	Norfolk QOL-DN is a 35-item participant-rated questionnaire used to assess the impact of diabetic neuropathy on quality of life of participants with diabetic neuropathy. All symptoms (1 - 7) are scored as either 1 or 0, indicating presence or absence of the symptom. Item 9 is scored according to the 5-point Likert Scale (0 - 4, "no problem" to "severe problem"). The symptoms domain score should be summed as follow: Σ (1 - 7, 9). The scales and subscales are calculated without weighting of any kind, and reported as the integer sum of the listed questionnaire items (range: 0 - 32). The QOL-DN version that was administered in this study was modified with a 2-week recall period.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	7.51 (0.25)	7.86 (0.25)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline symptoms domain score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.1769
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.35
	Confidence Interval	(2-Sided) 95%; -0.85 to 0.16
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.26
	Estimation Comments	[Not Specified]

11. Secondary Outcome

Title	Norfolk QOL-DN Activities of Daily Living Domain Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	Norfolk QOL-DN is a 35-item participant-rated questionnaire used to assess the impact of diabetic neuropathy on quality of life of participants with diabetic neuropathy. The items are scored according to the 5-point Likert Scale (0 - 4, "no problem" to "severe problem"). Activities of the daily living domain score should be summed as follow: Σ (12, 22, 23, 25, 26). Scales and subscales are calculated without weighting of any kind, and reported as integer sum of listed questionnaire items (range: 0 - 20). The QOL-DN version that was administered in the study was modified with a 2-week recall period.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	2.82 (0.16)	2.94 (0.16)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline activities of daily living domain score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.5119
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.12
	Confidence Interval	(2-Sided) 95%; -0.48 to 0.24
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.18
	Estimation Comments	[Not Specified]

12. Secondary Outcome

Title	Norfolk QOL-DN Physical Functioning / Large Fiber Domain Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	Norfolk QOL-DN is a 35-item participant-rated questionnaire used to assess the impact of diabetic neuropathy on quality of life of participants with diabetic neuropathy. With exception of questions 31 and 32, items are scored according to the 5-point Likert Scale (0 - 4, "no problem" to "severe problem"). In question 31, "good", middle item, is scored as 0, "very good" as -1 , "excellent" as -2, "fair" as 1, and "poor" as 2. In question 32, "about the same", middle item, is scored as 0, "somewhat better" as -1, "much better" as -2, "somewhat worse" as 1, and "much worse" as 2. Physical functioning / large fiber domain score should be summed as follow: Σ (8, 11, 13 - 15, 24, 27 - 35). Scales and subscales are calculated without weighting of any kind, and reported as integer sum of listed questionnaire items (range: -4 - 56). QOL-DN version that was administered in the study was modified with a 2-week recall period.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	23.17 (0.61)	23.66 (0.60)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline physical functioning / large fiber domain score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.4335
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.49
	Confidence Interval	(2-Sided) 95%; -1.72 to 0.74
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.62
	Estimation Comments	[Not Specified]

13. Secondary Outcome

Title	Norfolk QOL-DN Small Fiber Domain Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	Norfolk QOL-DN is a 35-item participant-rated questionnaire used to assess impact of diabetic neuropathy on quality of life of participants with diabetic neuropathy. The items are scored according to the 5-point Likert Scale (0 - 4, "no problem" to "severe problem"). The small fiber domain score should be summed as follow: Σ (10, 16, 17, 18). Scales and subscales are calculated without weighting of any kind, and reported as integer sum of the listed questionnaire items (range: 0 - 16). The QOL-DN version that was administered in this study was modified with a 2-week recall period.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	2.57 (0.16)	2.58 (0.16)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline small fiber domain score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.9653
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.01
	Confidence Interval	(2-Sided) 95%; -0.31 to 0.30
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.16
	Estimation Comments	[Not Specified]

14. Secondary Outcome

Title	Norfolk QOL-DN Autonomic Domain Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	Norfolk QOL-DN is a 35-item participant-rated questionnaire used to assess the impact of diabetic neuropathy on quality of life of participants with diabetic neuropathy. The items are scored according to the 5-point Likert Scale (0 - 4, "no problem" to "severe problem"). The autonomic domain score should be summed as follow: Σ (19, 20, 21). The scales and subscales are calculated without weighting of any kind, and reported as the integer sum of the listed questionnaire items (range: 0 - 12). The QOL-DN version that was administered in this study was modified with a 2-week recall period.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	1.12 (0.10)	1.26 (0.10)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline autonomic domain score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.2690
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.14
	Confidence Interval	(2-Sided) 95%; -0.38 to 0.11
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.12
	Estimation Comments	[Not Specified]

15. Secondary Outcome

Title	Euro QoL-5 Dimensions (EQ-5D) Mobility Domain Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	EQ-5D is a participant-completed 5-item questionnaire designed to assess health related quality of life in terms of a single index value or utility score. There are 5 dimensions: mobility, self-care, usual activities, pain / discomfort, and anxiety / depression. Each dimension is rated on a 3-point response scale (no problems, some/moderate problems, extreme problems) and the scores are combined to form a single index utility value between 0 and 1 with higher scores indicating better health.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	1.65 (0.03)	1.65 (0.03)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline mobility domain score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.9951
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	0.00
	Confidence Interval	(2-Sided) 95%; -0.05 to 0.05
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.03
	Estimation Comments	[Not Specified]

16. Secondary Outcome

Title	EQ-5D Self-Care Domain Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	EQ-5D is a participant-completed 5-item questionnaire designed to assess health related quality of life in terms of a single index value or utility score. There are 5 dimensions: mobility, self-care, usual activities, pain / discomfort, and anxiety / depression. Each dimension is rated on a 3-point response scale [1 = no problems, 2 = some/moderate problems, 3 = extreme problems] and the scores are combined to form a single index utility value between 0 and 1 with higher scores indicating better health.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	1.18 (0.02)	1.18 (0.02)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline self-care domain score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.9726
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	0.00
	Confidence Interval	(2-Sided) 95%; -0.05 to 0.05
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.02
	Estimation Comments	[Not Specified]

17. Secondary Outcome

Title	EQ-5D Usual Activities Domain Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	EQ-5D is a participant-completed 5-item questionnaire designed to assess health related quality of life in terms of a single index value or utility score. There are 5 dimensions: mobility, self-care, usual activities, pain / discomfort, and anxiety / depression. Each dimension is rated on a 3-point response scale [1 = no problems, 2 = some/moderate problems, 3 = extreme problems] and the scores are combined to form a single index utility value between 0 and 1 with higher scores indicating better health.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	1.53 (0.03)	1.51 (0.03)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline usual activities domain score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.5497
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	0.02
	Confidence Interval	(2-Sided) 95%; -0.04 to 0.08
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.03
	Estimation Comments	[Not Specified]

18. Secondary Outcome

Title	EQ-5D Pain / Discomfort Domain Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	EQ-5D is a participant-completed 5-item questionnaire designed to assess health related quality of life in terms of a single index value or utility score. There are 5 dimensions: mobility, self-care, usual activities, pain / discomfort, and anxiety / depression. Each dimension is rated on a 3-point response scale [1 = no problems, 2 = some/moderate problems, 3 = extreme problems] and the scores are combined to form a single index utility value between 0 and 1 with higher scores indicating better health.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	2.03 (0.03)	1.98 (0.02)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline pain / discomfort domain score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.1495
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	0.05
	Confidence Interval	(2-Sided) 95%; -0.02 to 0.11
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.03
	Estimation Comments	[Not Specified]

19. Secondary Outcome

Title	EQ-5D Anxiety / Depression Domain Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	EQ-5D is a participant-completed 5-item questionnaire designed to assess health related quality of life in terms of a single index value or utility score. There are 5 dimensions: mobility, self-care, usual activities, pain / discomfort, and anxiety / depression. Each dimension is rated on a 3-point response scale [1 = no problems, 2 = some/moderate problems, 3 = extreme problems] and the scores are combined to form a single index utility value between 0 and 1 with higher scores indicating better health.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	1.30 (0.03)	1.35 (0.03)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline anxiety / depression domain score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.1297
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.05
	Confidence Interval	(2-Sided) 95%; -0.11 to 0.01
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.03
	Estimation Comments	[Not Specified]

20. Secondary Outcome

Title	EQ-5D Dolan 1997 Index Summary Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	EQ-5D is a participant-completed 5-item questionnaire designed to assess health related quality of life in terms of a single index value or utility score. There are 5 dimensions: mobility, self-care, usual activities, pain / discomfort, and anxiety / depression. Each dimension is rated on a 3-point response scale [1 = no problems, 2 = some/moderate problems, 3 = extreme problems] and the scores are combined to form a single index utility value between 0 and 1 with higher scores indicating better health. The utility score is calculated using the Dolan 1997 algorithm and the revised version which was provided to the EuroQol Group by Dolan in 2001 - but later published in medical care in 2002.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	0.63 (0.01)	0.65 (0.01)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline Dolan 1997 index summary score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.4279
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.01
	Confidence Interval	(2-Sided) 95%; -0.04 to 0.02
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.01
	Estimation Comments	[Not Specified]

21. Secondary Outcome

Title	EQ-5D Dolan 2002 Index Summary Score at the End of Each Treatment Period (Week 6 of Each Treatment Period)
Description	EQ-5D is a participant-completed 5-item questionnaire designed to assess health related quality of life in terms of a single index value or utility score. There are 5 dimensions: mobility, self-care, usual activities, pain / discomfort, and anxiety / depression. Each dimension is rated on a 3-point response scale [1 = no problems, 2 = some/moderate problems, 3 = extreme problems] and the scores are combined to form a single index utility value between 0 and 1 with higher scores indicating better health. The utility score is calculated using the Dolan 1997 algorithm and the revised version which was provided to the EuroQol Group by Dolan in 2001 - but later published in medical care in 2002.
Time Frame	End of Period (includes both Visits 5 and 9)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	272	276
Least Squares Mean (Standard Error); Unit of Measure: units on a scale
	0.63 (0.01)	0.64 (0.01)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a linear mixed effects model which included baseline Dolan 2001 index summary score, sequence, period, and treatment as fixed effect factors and participant within sequence and within-participant error as random factors. The treatment difference (pregabalin - placebo) has been tested using within-participant variability as error term.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.5505
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Mixed Models Analysis
	Comments	[Not Specified]
Method of Estimation	Estimation Parameter	Mean Difference (Final Values)
	Estimated Value	-0.01
	Confidence Interval	(2-Sided) 95%; -0.04 to 0.02
	Parameter Dispersion	Type: Standard Error of the mean; Value: 0.01
	Estimation Comments	[Not Specified]

22. Secondary Outcome

Title	Patient Global Impression of Change (PGIC) Score at the End of Period 1 (Week 6) - Original Scores
Description	The PGIC is a participant-rated instrument that measures the participant`s assessment of change in his/her overall status on a scale ranging from 1 (very much improved) to 7 (very much worse). Due to the crossover design, PGIC was analyzed at the end of period 1 (V5).
Time Frame	End of Period 1 (V5)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period. All participants who were randomized and had a period 1 PGIC value were used for this analysis.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	148	143
Measure Type: Number; Unit of Measure: percentage of participants
Very much improved	8.1	4.9
Much improved	27.7	19.6
Minimally improved	39.2	39.2
No change	14.9	23.1
Minimally worse	6.1	7.0
Much worse	2.0	1.4
Very much worse	1.4	2.1
Missing	0.7	2.8

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a Cochran-Mantel-Haenszel (CMH) test with modified ridit transformation, under alternative hypothesis of raw mean scores differ.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.0604
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Cochran-Mantel-Haenszel
	Comments	[Not Specified]

23. Secondary Outcome

Title	PGIC Score at the End of Period 1 (Week 6) - Categorized Scores
Description	The PGIC is a participant-rated instrument that measures the participant`s assessment of change in his/her overall status on a scale ranging from 1 (very much improved) to 7 (very much worse). Original scores (7 different scores) and categorized scores (4 different scores) were provided. Categorized scores were very much improved (consisting of very much improved and much improved); any improvement (consisting of very much improved, much improved, and minimally improved); no change (consisting of no change); and any worsening (consisting of minimally worse, much worse, and very much worse). Due to the crossover design, PGIC was analyzed at the end of period 1 (V5).
Time Frame	End of Period 1 (V5)

Outcome Measure Data

Analysis Population Description

The ITT population included all randomized participants with at least one dose of study drug. The ITT population was analyzed according to what the randomization schedule intended for the participants to take in each period. All participants who were randomized and had a period 1 PGIC value were used for this analysis.

Arm/Group Title	Pregabalin	Placebo
Arm/Group Description:	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
Overall Number of Participants Analyzed	148	143
Measure Type: Number; Unit of Measure: percentage of participants
Very much/much improved	35.8	24.5
Any improvement	75.0	63.6
No change	14.9	23.1
Any worsening	9.5	10.5

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Pregabalin, Placebo
	Comments	Analysis was done using a CMH test with modified ridit transformation, under alternative hypothesis of raw mean scores differ.
	Type of Statistical Test	Superiority or Other
	Comments	[Not Specified]
Statistical Test of Hypothesis	P-Value	0.1511
	Comments	Secondary analysis was two-sided and performed at the 0.05 significance level, without multiple comparisons' adjustment.
	Method	Cochran-Mantel-Haenszel
	Comments	[Not Specified]

Adverse Events

Time Frame	From the time the participants were randomized through and including 28 calender days after the last administration of the study drug.
Adverse Event Reporting Description	The same event may appear as both an AE and a SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as nonserious in another participant, or one participant may have experienced both a serious and nonserious event during the study.
Arm/Group Title	Pregabalin	Placebo
Arm/Group Description	The below tables included data from participants while receiving pregabalin in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6- week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.	The below table included data from participants while receiving placebo in either period of the 2-period crossover study design. This crossover study consisted of two double blind 6-week treatment periods where participants were randomized to pregabalin or placebo for the first period, and were then switched to the other treatment for the second period. There was a 2-week single-blind washout (blinded to participant) between the treatment periods. A 1-week taper was administered at the end of the second treatment period, followed by a final follow-up visit.
All-Cause Mortality
	Pregabalin	Placebo
	Affected / at Risk (%)	Affected / at Risk (%)
Total	--/--	--/--
Serious Adverse Events
	Pregabalin	Placebo
	Affected / at Risk (%)	Affected / at Risk (%)
Total	5/272 (1.84%)	7/276 (2.54%)
Cardiac disorders
Angina pectoris * 1	1/272 (0.37%)	0/276 (0.00%)
Atrial fibrillation * 1	1/272 (0.37%)	0/276 (0.00%)
Myocardial infarction * 1	1/272 (0.37%)	0/276 (0.00%)
Gastrointestinal disorders
Abdominal pain upper * 1	0/272 (0.00%)	1/276 (0.36%)
Gastritis * 1	0/272 (0.00%)	1/276 (0.36%)
Pancreatitis acute * 1	0/272 (0.00%)	1/276 (0.36%)
General disorders
Multi-organ failure * 1	1/272 (0.37%)	0/276 (0.00%)
Infections and infestations
Bronchitis * 1	1/272 (0.37%)	0/276 (0.00%)
Escherichia bacteraemia * 1	1/272 (0.37%)	0/276 (0.00%)
Localised infection * 1	0/272 (0.00%)	1/276 (0.36%)
Lung abscess * 1	0/272 (0.00%)	1/276 (0.36%)
Metabolism and nutrition disorders
Hyperglycaemia * 1	1/272 (0.37%)	0/276 (0.00%)
Nervous system disorders
Cerebrovascular accident * 1	0/272 (0.00%)	1/276 (0.36%)
Ischaemic cerebral infarction * 1	0/272 (0.00%)	1/276 (0.36%)
Vascular disorders
Hypertension * 1	0/272 (0.00%)	1/276 (0.36%)
* Indicates events were collected by non-systematic assessment; 1 Term from vocabulary, MedDRA v17.0
Other (Not Including Serious) Adverse Events
Frequency Threshold for Reporting Other Adverse Events	2%
	Pregabalin	Placebo
	Affected / at Risk (%)	Affected / at Risk (%)
Total	84/272 (30.88%)	45/276 (16.30%)
Gastrointestinal disorders
Diarrhoea * 1	9/272 (3.31%)	11/276 (3.99%)
Nausea * 1	9/272 (3.31%)	8/276 (2.90%)
General disorders
Fatigue * 1	14/272 (5.15%)	4/276 (1.45%)
Oedema peripheral * 1	10/272 (3.68%)	8/276 (2.90%)
Musculoskeletal and connective tissue disorders
Arthralgia * 1	8/272 (2.94%)	4/276 (1.45%)
Pain in extremity * 1	7/272 (2.57%)	5/276 (1.81%)
Nervous system disorders
Dizziness * 1	28/272 (10.29%)	4/276 (1.45%)
Headache * 1	9/272 (3.31%)	8/276 (2.90%)
Somnolence * 1	14/272 (5.15%)	7/276 (2.54%)
* Indicates events were collected by non-systematic assessment; 1 Term from vocabulary, MedDRA v17.0

Limitations and Caveats

[Not Specified]

More Information

Certain Agreements

Principal Investigators are NOT employed by the organization sponsoring the study.

There IS an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.

Pfizer has the right to review disclosures, requesting a delay of less than 60 days. Investigator will postpone single center publications until after disclosure of pooled data (all sites), less than 12 months from study completion/termination at all participating sites. Investigator may not disclose previously undisclosed confidential information other than study results.

Results Point of Contact

• Name/Title: Pfizer ClinicalTrials.gov Call Center
• Organization: Pfizer, Inc.
• Phone: 1-800-718-1021
• EMail: ClinicalTrials.gov_Inquiries@pfizer.com

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):

Raskin P, Huffman C, Yurkewicz L, Pauer L, Scavone JM, Yang R, Parsons B. Pregabalin in Patients With Painful Diabetic Peripheral Neuropathy Using an NSAID for Other Pain Conditions: A Double-Blind Crossover Study. Clin J Pain. 2016 Mar;32(3):203-10. doi: 10.1097/AJP.0000000000000254.

• Responsible Party: Pfizer
• ClinicalTrials.gov Identifier: NCT01455415
• Other Study ID Numbers: A0081268; 2011-002743-10 ( EudraCT Number )
• First Submitted: October 17, 2011
• First Posted: October 20, 2011
• Results First Submitted: October 30, 2014
• Results First Posted: April 23, 2015
• Last Update Posted: April 23, 2015