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Pregabalin in the Treatment of Patients With Generalized Anxiety Disorder (GAD).

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ClinicalTrials.gov Identifier: NCT00413010
Recruitment Status : Completed
First Posted : December 19, 2006
Results First Posted : December 2, 2009
Last Update Posted : December 9, 2009
Sponsor:
Information provided by:
Pfizer

Study Type Interventional
Study Design Allocation: Randomized;   Intervention Model: Parallel Assignment;   Masking: Double (Participant, Investigator);   Primary Purpose: Treatment
Condition Generalized Anxiety Disorder
Interventions Drug: pregabalin
Drug: placebo
Enrollment 356
Recruitment Details The study was conducted in 55 centers in 8 countries (United States, Russian Federation, Czech Republic, Ukraine, Serbia, Hungary, Finland, and Estonia).
Pre-assignment Details After a screening phase (Period 1), subjects entered an 8-week open-label treatment optimzation phase (Period 2). Only those subjects who partially responded to background Generalized Anxiety Disorder (GAD) treatment (escitalopram, paroxetine, or venlafaxine XR) and met all inclusion/exclusion criteria were eligible for randomization (Period 3).
Arm/Group Title Pregabalin Placebo
Hide Arm/Group Description Pregabalin doses of 150 milligrams (mg)/day, 300 mg/day, 450 mg/day, and 600 mg/day was administered orally, twice daily (BID), with or without food, during the double-blind phase. Flexible dosing of pregabalin was allowed during the first 6 weeks; fixed dosing was required for the last 2 weeks of this period.Subjects were required to remain on a stable dose of their concurrent Generalized Anxiety Disorder (GAD) treatment (ie, escitalopram, paroxetine, or venlafaxine XR). Placebo was administrated orally, twice daily (BID) with or without food, during the double-blind phase. Subjects were required to remain on a stable dose of their concurrent GAD treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Period Title: Overall Study
Started 180 176
Completed 108 113
Not Completed 72 63
Reason Not Completed
Adverse Event             8             4
Laboratory abnormality             0             2
Lack of Efficacy             0             3
Lost to Follow-up             3             0
Withdrawal by Subject             7             2
Due to termination of the study             54             52
Arm/Group Title Pregabalin Placebo Total
Hide Arm/Group Description Pregabalin doses of 150 milligrams (mg)/day, 300 mg/day, 450 mg/day, and 600 mg/day was administered orally, twice daily (BID), with or without food, during the double-blind phase. Flexible dosing of pregabalin was allowed during the first 6 weeks; fixed dosing was required for the last 2 weeks of this period.Subjects were required to remain on a stable dose of their concurrent Generalized Anxiety Disorder (GAD) treatment (ie, escitalopram, paroxetine, or venlafaxine XR). Placebo was administrated orally, twice daily (BID) with or without food, during the double-blind phase. Subjects were required to remain on a stable dose of their concurrent GAD treatment (ie, escitalopram, paroxetine, or venlafaxine XR). Total of all reporting groups
Overall Number of Baseline Participants 180 176 356
Hide Baseline Analysis Population Description
[Not Specified]
Age Continuous  
Mean (Standard Deviation)
Unit of measure:  Years
Number Analyzed 180 participants 176 participants 356 participants
43.7  (11.5) 43.5  (12.5) 43.6  (12.0)
Sex: Female, Male  
Measure Type: Count of Participants
Unit of measure:  Participants
Number Analyzed 180 participants 176 participants 356 participants
Female
129
  71.7%
115
  65.3%
244.0
Male
51
  28.3%
61
  34.7%
112.0
1.Primary Outcome
Title Change in Hamilton Anxiety Rating Scale (HAM-A) Total Scores
Hide Description Change from baseline: average across visit weeks using mixed model. HAM-A=clinician-rated interview measuring presence of anxiety-related symptoms in 14 areas including anxiety, tension, depressed mood, palpitations, breathing difficulties, sleep disturbances, & restlessness. Total score ranges from 0 to 56; higher score indicates greater anxiety.
Time Frame Baseline, 8 weeks
Hide Outcome Measure Data
Hide Analysis Population Description
Intent-to-Treat (ITT) population included all randomized subjects who had received at least 1 dose of the double-blind treatment. All efficacy analyses included the ITT subjects who had a Baseline and a post-Baseline assessment of the respective efficacy endpoints.
Arm/Group Title Pregabalin Placebo
Hide Arm/Group Description:
Pregabalin doses of 150 milligrams (mg)/day, 300 mg/day, 450 mg/day, and 600 mg/day was administered orally, twice daily (BID), with or without food, during the double-blind phase. Flexible dosing of pregabalin was allowed during the first 6 weeks; fixed dosing was required for the last 2 weeks of this period.Subjects were required to remain on a stable dose of their concurrent Generalized Anxiety Disorder (GAD) treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Placebo was administrated orally, twice daily (BID) with or without food, during the double-blind phase. Subjects were required to remain on a stable dose of their concurrent GAD treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Overall Number of Participants Analyzed 177 176
Least Squares Mean (Standard Error)
Unit of Measure: score on scale
-7.6  (0.35) -6.4  (0.36)
Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Null hypothesis: no difference between Pregabalin (150-600 mg/day) BID and Placebo BID treatment groups. An initial sample size of 173 subjects per double-blind treatment group was calculated to provide at least 90% power to detect an effect size (ie, difference in the true means between 2 treatment groups/standard deviation) of 0.36 for the HAM-A total score change from Baseline using a 2-sided nominal significance level of 4.9%.
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method Mixed Models Analysis
Comments Adjusted for treatment, pooled center baseline, HAM-A total score,time,and treatment-by time
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -1.2
Confidence Interval 95%
-2.16 to -0.26
Parameter Dispersion
Type: Standard Error of the mean
Value: 0.48
Estimation Comments Since an interim analysis was conducted and the sample size was larger than the targeted 173 subjects per group, a critical t-value adjustment was 1.977, yielding an adjusted 95% CI shown above.
2.Secondary Outcome
Title Change in HAM-A Total Score at Weekly Visits
Hide Description Change: score at each study week minus score at baseline. HAM-A, a clinician-rated interview, measures presence of anxiety-related symptoms in 14 areas including anxiety, tension, depressed mood, palpitations, breathing difficulties, sleep disturbances, & restlessness. Total score ranges from 0 to 56; higher score indicates greater anxiety.
Time Frame Baseline, Weeks 1 through Week 8
Hide Outcome Measure Data
Hide Analysis Population Description
Intent-to-Treat (ITT) population included all randomized subjects who had received at least 1 dose of the double-blind treatment. All efficacy analyses included the ITT subjects who had a Baseline and a post-Baseline assessment of the respective efficacy endpoints.
Arm/Group Title Pregabalin Placebo
Hide Arm/Group Description:
Pregabalin doses of 150 milligrams (mg)/day, 300 mg/day, 450 mg/day, and 600 mg/day was administered orally, twice daily (BID), with or without food, during the double-blind phase. Flexible dosing of pregabalin was allowed during the first 6 weeks; fixed dosing was required for the last 2 weeks of this period.Subjects were required to remain on a stable dose of their concurrent Generalized Anxiety Disorder (GAD) treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Placebo was administrated orally, twice daily (BID) with or without food, during the double-blind phase. Subjects were required to remain on a stable dose of their concurrent GAD treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Overall Number of Participants Analyzed 177 176
Least Squares Mean (Standard Error)
Unit of Measure: score on scale
Week 1 (n=164;n=169) -4.4  (0.37) -3.1  (0.37)
Week 2 (n=166;n=163) -6.3  (0.43) -5.2  (0.43)
Week 3 (n=157;n=160) -7.0  (0.45) -5.5  (0.45)
Week 4 (n=153;n=150) -8.3  (0.46) -7.0  (0.47)
Week 5 (n=135;n=130) -8.4  (0.49) -7.6  (0.49)
Week 6 (n=122;n=125) -9.2  (0.49) -8.0  (0.49)
Week 8 (n=126;n=127) -9.3  (0.56) -8.0  (0.56)
Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 1
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method Mixed Models Analysis
Comments Treatment (tx) adjusted, pooled center baseline HAM-A total score,time,and tx-by time. Degrees of freedom adjusted using Satterthwaite approximation
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -1.33
Confidence Interval 95%
-2.3 to -0.4
Parameter Dispersion
Type: Standard Error of the mean
Value: 0.49
Estimation Comments Difference reflects pregabalin minus placebo.
Hide Statistical Analysis 2
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 2
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method Mixed Models Analysis
Comments Treatment (tx) adjusted, pooled center baseline HAM-A total score,time,and tx-by time. Degrees of freedom adjusted using Satterthwaite approximation
Method of Estimation Estimation Parameter Median Difference (Final Values)
Estimated Value -1.04
Confidence Interval 95%
-2.2 to 0.1
Parameter Dispersion
Type: Standard Error of the mean
Value: 0.59
Estimation Comments Difference reflects pregabalin minus placebo.
Hide Statistical Analysis 3
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 3
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method Mixed Models Analysis
Comments Treatment (tx) adjusted, pooled center baseline HAM-A total score,time,and tx-by time. Degrees of freedom adjusted using Satterthwaite approximation
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -1.45
Confidence Interval 95%
-2.7 to -0.2
Parameter Dispersion
Type: Standard Error of the mean
Value: 0.62
Estimation Comments Difference reflects pregabalin minus placebo.
Hide Statistical Analysis 4
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 4
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method Mixed Models Analysis
Comments Treatment (tx) adjusted, pooled center baseline HAM-A total score,time,and tx-by time. Degrees of freedom adjusted using Satterthwaite approximation
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -1.33
Confidence Interval 95%
-2.6 to -0.1
Parameter Dispersion
Type: Standard Error of the mean
Value: 0.64
Estimation Comments Difference reflects pregabalin minus placebo.
Hide Statistical Analysis 5
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 5
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method Mixed Models Analysis
Comments Treatment (tx) adjusted, pooled center baseline HAM-A total score,time,and tx-by time. Degrees of freedom adjusted using Satterthwaite approximation
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -0.78
Confidence Interval 95%
-2.1 to 0.5
Parameter Dispersion
Type: Standard Error of the mean
Value: 0.68
Estimation Comments Difference reflects pregabalin minus placebo.
Hide Statistical Analysis 6
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 6
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method Mixed Models Analysis
Comments Treatment (tx) adjusted, pooled center baseline HAM-A total score,time,and tx-by time. Degrees of freedom adjusted using Satterthwaite approximation
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -1.22
Confidence Interval 95%
-2.5 to 0.1
Parameter Dispersion
Type: Standard Error of the mean
Value: 0.67
Estimation Comments Difference reflects pregabalin minus placebo.
Hide Statistical Analysis 7
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 8
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method Mixed Models Analysis
Comments Treatment (tx) adjusted, pooled center baseline HAM-A total score,time,and tx-by time. Degrees of freedom adjusted using Satterthwaite approximation
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -1.35
Confidence Interval 95%
-2.9 to 0.2
Parameter Dispersion
Type: Standard Error of the mean
Value: 0.77
Estimation Comments Difference reflects pregabalin minus placebo.
3.Secondary Outcome
Title Number of Responders Using Hamilton Anxiety Rating Scale (HAM-A)
Hide Description Responders = YES if subjects achieved a >= 50% decrease in HAM-A total score from Baseline to respective study week. HAM-A is a clinician-rated interview measuring the presence of anxiety-related symptoms in 14 areas. Total score ranges from 0 to 56; higher score indicates greater anxiety.
Time Frame Weeks 1 through Week 8
Hide Outcome Measure Data
Hide Analysis Population Description
Intent-to-Treat (ITT) population included all randomized subjects who had received at least 1 dose of the double-blind treatment, and had a baseline and post-baseline efficacy assessment.
Arm/Group Title Pregabalin Placebo
Hide Arm/Group Description:
Pregabalin doses of 150 milligrams (mg)/day, 300 mg/day, 450 mg/day, and 600 mg/day was administered orally, twice daily (BID), with or without food, during the double-blind phase. Flexible dosing of pregabalin was allowed during the first 6 weeks; fixed dosing was required for the last 2 weeks of this period.Subjects were required to remain on a stable dose of their concurrent Generalized Anxiety Disorder (GAD) treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Placebo was administrated orally, twice daily (BID) with or without food, during the double-blind phase. Subjects were required to remain on a stable dose of their concurrent GAD treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Overall Number of Participants Analyzed 177 176
Measure Type: Number
Unit of Measure: participants
Week 1 Responder: Yes 21 8
Week 1 Responder: No 143 161
Week 2 Responder: Yes 39 26
Week 2 Responder: No 127 137
Week 3 Responder: Yes 51 23
Week 3 Responder: No 106 137
Week 4 Responder: Yes 64 46
Week 4 Responder: No 89 104
Week 5 Responder: Yes 58 46
Week 5 Responder: No 77 84
Week 6 Responder: Yes 57 48
Week 6 Responder: No 65 77
Week 8 Responder: Yes 63 47
Week 8 Responder: No 63 80
Week 8 (LOCF) Responder: Yes 84 62
Week 8 (LOCF) Responder: No 93 114
Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 1
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less that the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald’s Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A responders at each week with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 3.35
Confidence Interval 95%
1.37 to 8.24
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
Hide Statistical Analysis 2
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 2
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald's Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A responsers at each each with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.61
Confidence Interval 95%
0.90 to 2.87
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
Hide Statistical Analysis 3
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 3
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald's Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A responsers at each each with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 3.15
Confidence Interval 95%
1.76 to 5.66
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
Hide Statistical Analysis 4
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 4
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald's Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A responsers at each each with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.80
Confidence Interval 95%
1.06 to 3.05
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
Hide Statistical Analysis 5
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 5
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald's Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A responsers at each each with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.57
Confidence Interval 95%
0.90 to 2.73
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
Hide Statistical Analysis 6
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 6
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald's Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A responsers at each each with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.52
Confidence Interval 95%
0.86 to 2.66
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
Hide Statistical Analysis 7
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 8
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald's Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A responsers at each each with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.86
Confidence Interval 95%
1.08 to 3.22
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
Hide Statistical Analysis 8
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 8 (last observation carried forward, LOCF)
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald's Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A responders at Week 8 (LOCF) with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.77
Confidence Interval 95%
1.12 to 2.79
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
4.Secondary Outcome
Title Subjects in Remission Using Hamilton Anxiety Rating Scale (HAM-A) Total Score
Hide Description Participant in remission defined as HAM-A total score of <= 7. HAM-A=clinician-rated interview measuring presence of anxiety-related symptoms in 14 areas including anxiety, tension, depressed mood, palpitations, breathing difficulties, sleep disturbances, & restlessness. Total score ranges 0 - 56; higher score indicates greater anxiety.
Time Frame Week 1 through Week 8
Hide Outcome Measure Data
Hide Analysis Population Description
Intent-to-Treat (ITT) population included all randomized subjects who had received at least 1 dose of the double-blind treatment, and had a baseline and post-baseline efficacy assessment.
Arm/Group Title Pregabalin Placebo
Hide Arm/Group Description:
Pregabalin doses of 150 milligrams (mg)/day, 300 mg/day, 450 mg/day, and 600 mg/day was administered orally, twice daily (BID), with or without food, during the double-blind phase. Flexible dosing of pregabalin was allowed during the first 6 weeks; fixed dosing was required for the last 2 weeks of this period.Subjects were required to remain on a stable dose of their concurrent Generalized Anxiety Disorder (GAD) treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Placebo was administrated orally, twice daily (BID) with or without food, during the double-blind phase. Subjects were required to remain on a stable dose of their concurrent GAD treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Overall Number of Participants Analyzed 177 176
Measure Type: Number
Unit of Measure: participants
Week 1 Remission: Yes 12 5
Week 1 Remission: No 152 164
Week 2 Remission: Yes 22 15
Week 2 Remission: No 144 148
Week 3 Remission: Yes 32 18
Week 3 Remission: No 125 142
Week 4 Remission: Yes 43 29
Week 4 Remission: No 110 121
Week 5 Remission: Yes 39 30
Week 5 Remission: No 96 100
Week 6 Remission: Yes 37 32
Week 6 Remission: No 85 93
Week 8 Remission: Yes 40 31
Week 8 Remission: No 86 96
Week 8 (LOCF) Remission: Yes 55 42
Week 8 (LOCF) Remission: No 122 134
Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 1
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less that the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald’s Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A remission at Week 8 with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 2.88
Confidence Interval 95%
0.94 to 8.80
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a remitter (yes) for pregabalin relative to the odds of being a remitter for placebo.
Hide Statistical Analysis 2
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 2
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less that the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald’s Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A remission at Week 8 with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.49
Confidence Interval 95%
0.72 to 3.06
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a remitter (yes) for pregabalin relative to the odds of being a remitter for placebo.
Hide Statistical Analysis 3
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 3
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less that the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald’s Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A remission at Week 8 with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 2.08
Confidence Interval 95%
1.09 to 3.97
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a remitter (yes) for pregabalin relative to the odds of being a remitter for placebo.
Hide Statistical Analysis 4
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 4
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less that the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald’s Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A remission at Week 8 with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.80
Confidence Interval 95%
0.99 to 3.28
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a remitter (yes) for pregabalin relative to the odds of being a remitter for placebo.
Hide Statistical Analysis 5
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 5
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less that the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald’s Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A remission at Week 8 with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.53
Confidence Interval 95%
0.82 to 2.85
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a remitter (yes) for pregabalin relative to the odds of being a remitter for placebo.
Hide Statistical Analysis 6
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 6
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less that the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald’s Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A remission at Week 8 with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.33
Confidence Interval 95%
0.71 to 2.48
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a remitter (yes) for pregabalin relative to the odds of being a remitter for placebo.
Hide Statistical Analysis 7
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 8
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less that the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald’s Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A remission at Week 8 with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.55
Confidence Interval 95%
0.85 to 2.83
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a remitter (yes) for pregabalin relative to the odds of being a remitter for placebo.
Hide Statistical Analysis 8
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 8 Last Observation Carried Foward (LOCF)
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method Regression, Logistic
Comments Based on fitting a logistic regression on the HAM-A responders at Week 8 (LOCF) with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.53
Confidence Interval 95%
0.92 to 2.53
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a remitter (yes) for pregabalin relative to the odds of being a remitter for placebo.
5.Secondary Outcome
Title Time to Onset of Sustained Hamilton Anxiety Rating Scale (HAM-A) Improvement
Hide Description Time to sustained improvement was defined as time to 50% or greater reduction in HAM-A total score from Baseline, which was sustained for the remainder of the study. HAM-A is a clinician-rated interview measuring the presence of anxiety-related symptoms in 14 areas. Total score ranges from 0 to 56; a higher score indicates greater anxiety.
Time Frame Week 8
Hide Outcome Measure Data
Hide Analysis Population Description
Intent-to-Treat (ITT) population included all randomized subjects who had received at least 1 dose of the double-blind treatment, and had a baseline and post-baseline efficacy assessment. CI for placebo patients was not estimable.
Arm/Group Title Pregabalin Placebo
Hide Arm/Group Description:
Pregabalin doses of 150 milligrams (mg)/day, 300 mg/day, 450 mg/day, and 600 mg/day was administered orally, twice daily (BID), with or without food, during the double-blind phase. Flexible dosing of pregabalin was allowed during the first 6 weeks; fixed dosing was required for the last 2 weeks of this period.Subjects were required to remain on a stable dose of their concurrent Generalized Anxiety Disorder (GAD) treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Placebo was administrated orally, twice daily (BID) with or without food, during the double-blind phase. Subjects were required to remain on a stable dose of their concurrent GAD treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Overall Number of Participants Analyzed 177 0
Median (95% Confidence Interval)
Unit of Measure: days
57
(43.0 to 61.0)
Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Kaplan Meier product limit estimate for calculating median time in days to onset sustained HAM-A Improvement.
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value 0.0137
Comments P-value corresponds to the 2-sided log-rank test.
Method Log Rank
Comments 2-sided log-rank test
6.Secondary Outcome
Title Number of Responders Using Clinical Global Impression of Improvement (CGI-I) Score
Hide Description Responders = YES using CGI-I if score indicated much improved or very much improved at the last study week. CGI-I is a clinician-rated instrument that measures change in subject's overall status on a 7-point scale ranging from 1 (very much improved) to 7 (very much worse).
Time Frame Week 1 through Week 8
Hide Outcome Measure Data
Hide Analysis Population Description
Intent-to-Treat (ITT) population included all randomized subjects who had received at least 1 dose of the double-blind treatment, and had a baseline and post-baseline efficacy assessment.
Arm/Group Title Pregabalin Placebo
Hide Arm/Group Description:
Pregabalin doses of 150 milligrams (mg)/day, 300 mg/day, 450 mg/day, and 600 mg/day was administered orally, twice daily (BID), with or without food, during the double-blind phase. Flexible dosing of pregabalin was allowed during the first 6 weeks; fixed dosing was required for the last 2 weeks of this period.Subjects were required to remain on a stable dose of their concurrent Generalized Anxiety Disorder (GAD) treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Placebo was administrated orally, twice daily (BID) with or without food, during the double-blind phase. Subjects were required to remain on a stable dose of their concurrent GAD treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Overall Number of Participants Analyzed 177 176
Measure Type: Number
Unit of Measure: participants
Week 1: Yes 62 49
Week 1: No 101 120
Week 2: Yes 94 74
Week 2: No 72 89
Week 3: Yes 93 76
Week 3: No 62 86
Week 4: Yes 97 88
Week 4: No 55 61
Week 5: Yes 89 81
Week 5: No 45 50
Week 6: Yes 83 76
Week 6: No 38 49
Week 8: Yes 80 82
Week 8: No 43 45
Week 8 (LOCF): Yes 113 110
Week 8 (LOCF): No 61 66
Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 1
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald’s Chi square test.
Method Regression, Logistic
Comments Based on fitting a logistic regression on the CGI-I responders at Week 8 with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.54
Confidence Interval 95%
0.96 to 2.47
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
Hide Statistical Analysis 2
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 2
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald's Chi square test.
Method Regression, Logistic
Comments [Not Specified]
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.58
Confidence Interval 95%
1.01 to 2.47
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
Hide Statistical Analysis 3
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 3
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald's Chi square test.
Method Regression, Logistic
Comments [Not Specified]
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.75
Confidence Interval 95%
1.09 to 2.82
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
Hide Statistical Analysis 4
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 4
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald's Chi square test.
Method Regression, Logistic
Comments [Not Specified]
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.26
Confidence Interval 95%
0.77 to 2.05
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
Hide Statistical Analysis 5
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 5
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald's Chi square test.
Method Regression, Logistic
Comments [Not Specified]
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.24
Confidence Interval 95%
0.72 to 2.11
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
Hide Statistical Analysis 6
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 6
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method Regression, Logistic
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald's Chi square test.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.45
Confidence Interval 95%
0.84 to 2.50
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
Hide Statistical Analysis 7
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 8
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald's Chi square test.
Method Regression, Logistic
Comments [Not Specified]
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.06
Confidence Interval 95%
0.61 to 1.84
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
Hide Statistical Analysis 8
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 8 (LOCF) Last Observation Carried Forward
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald's Chi square test.
Method Regression, Logistic
Comments [Not Specified]
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.12
Confidence Interval 95%
0.71 to 1.76
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. Odds of being a responder (yes) for pregabalin relative to the odds of being a responder for placebo.
7.Secondary Outcome
Title Clinical Global Impression of Severity (CGI-S) Score
Hide Description CGI-S is a clinician-rated instrument measuring the severity of a subject's symptoms on a 7-point categorical scale. Scores range from 1 (not at all ill) to 7 (among the most extremely ill patients). Higher score indicates that the subject is more ill.
Time Frame Week 8
Hide Outcome Measure Data
Hide Analysis Population Description
Intent-to-Treat (ITT) population included all randomized subjects who had received at least 1 dose of the double-blind treatment, and had a baseline and post-baseline efficacy assessment.
Arm/Group Title Pregabalin Placebo
Hide Arm/Group Description:
Pregabalin doses of 150 milligrams (mg)/day, 300 mg/day, 450 mg/day, and 600 mg/day was administered orally, twice daily (BID), with or without food, during the double-blind phase. Flexible dosing of pregabalin was allowed during the first 6 weeks; fixed dosing was required for the last 2 weeks of this period.Subjects were required to remain on a stable dose of their concurrent Generalized Anxiety Disorder (GAD) treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Placebo was administrated orally, twice daily (BID) with or without food, during the double-blind phase. Subjects were required to remain on a stable dose of their concurrent GAD treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Overall Number of Participants Analyzed 177 176
Measure Type: Number
Unit of Measure: participants
Normal, not ill at all 28 18
Borderline, mentally ill 49 37
Mildly ill 49 63
Moderately ill 46 48
Markedly ill 2 8
Severely ill 2 1
Among the most extremely ill 0 0
Not assessed 0 1
Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 8 Last Observation Carried Forward (LOCF)
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments P-value less than the nominal 0.05 level is suggestive of a treatment difference; P-value corresponds to Wald’s Chi square test.
Method Cumulative Logit Model
Comments Based on fitting a logistic regression model for ordinal response of CGI-S scores at Week 8 (LOCF) with treatment and center in the model.
Method of Estimation Estimation Parameter Odds Ratio (OR)
Estimated Value 1.56
Confidence Interval 95%
1.07 to 2.30
Estimation Comments The odds ratio represented the odds of demonstrating an improvement comparing pregabalin versus placebo. The odds of having an increasingly better response for pregabalin relative to the odds of having an increasingly better response for placebo.
8.Secondary Outcome
Title Change in Hamilton Depression Rating Scale (HAM-D) Total Score
Hide Description Change: score at each study week minus score at baseline. HAM-D, clinician-rated interview, measures presence of depressive symptoms in 17 areas (symptoms such as depressed mood, guilty feelings, suicide, sleep disturbances, anxiety levels, & weight loss). Total score ranges from 0 to 52; higher scores indicate more depression.
Time Frame Weeks 1 through Week 8
Hide Outcome Measure Data
Hide Analysis Population Description
Intent-to-Treat (ITT) population included all randomized subjects who had received at least 1 dose of the double-blind treatment, and had a baseline and post-baseline efficacy assessment.
Arm/Group Title Pregabalin Placebo
Hide Arm/Group Description:
Pregabalin doses of 150 milligrams (mg)/day, 300 mg/day, 450 mg/day, and 600 mg/day was administered orally, twice daily (BID), with or without food, during the double-blind phase. Flexible dosing of pregabalin was allowed during the first 6 weeks; fixed dosing was required for the last 2 weeks of this period.Subjects were required to remain on a stable dose of their concurrent Generalized Anxiety Disorder (GAD) treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Placebo was administrated orally, twice daily (BID) with or without food, during the double-blind phase. Subjects were required to remain on a stable dose of their concurrent GAD treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
Overall Number of Participants Analyzed 177 176
Least Squares Mean (Standard Error)
Unit of Measure: score on scale
Week 1 n=165,168 -2.1  (0.28) -1.3  (0.28)
Week 2 n=165,164 -3.1  (0.30) -2.4  (0.31)
Week 3 n=156,160 -3.5  (0.32) -2.8  (0.32)
Week 4 n=153, 149 -4.7  (0.29) -3.3  (0.29)
Week 5 n=135, 130 -4.3  (0.33) -3.9  (0.34)
Week 6 n=122, 125 -4.7  (0.33) -3.8  (0.33)
Week 8 n= 126, 127 -4.8  (0.40) -3.8  (0.40)
Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 1
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method ANCOVA
Comments Repeated analysis of covariance heterogeneous auto-regressive w/ tx center wk & tx by wk fixed effects; Baseline HAM-D total score covariate in model.
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -0.8
Confidence Interval 95%
-1.5 to 0.0
Estimation Comments Difference is pregabalin minus placebo.
Hide Statistical Analysis 2
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 2
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method ANCOVA
Comments Repeated analysis of covariance heterogeneous auto-regressive w/ tx center wk & tx by wk fixed effects; Baseline HAM-D total score covariate in model.
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -0.6
Confidence Interval 95%
-1.5 to 0.2
Estimation Comments Difference is pregabalin minus placebo.
Hide Statistical Analysis 3
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 3
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method ANCOVA
Comments Repeated analysis of covariance heterogeneous auto-regressive w/ tx center wk & tx by wk fixed effects; Baseline HAM-D total score covariate in model.
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -0.7
Confidence Interval 95%
-1.6 to 0.1
Estimation Comments Difference is pregabalin minus placebo.
Hide Statistical Analysis 4
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 4
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method ANCOVA
Comments Repeated analysis of covariance heterogeneous auto-regressive w/ tx center wk & tx by wk fixed effects; Baseline HAM-D total score covariate in model.
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -1.3
Confidence Interval 95%
-2.1 to -0.6
Estimation Comments Difference is pregabalin minus placebo.
Hide Statistical Analysis 5
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 5
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method ANCOVA
Comments Repeated analysis of covariance heterogeneous auto-regressive w/ tx center wk & tx by wk fixed effects; Baseline HAM-D total score covariate in model.
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -0.4
Confidence Interval 95%
-1.3 to 0.5
Estimation Comments Difference is pregabalin minus placebo.
Hide Statistical Analysis 6
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 6
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method ANCOVA
Comments Repeated analysis of covariance heterogeneous auto-regressive w/ tx center wk & tx by wk fixed effects; Baseline HAM-D total score covariate in model.
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -0.9
Confidence Interval 95%
-1.8 to 0.0
Estimation Comments Difference is pregabalin minus placebo.
Hide Statistical Analysis 7
Statistical Analysis Overview Comparison Group Selection Pregabalin, Placebo
Comments Week 8
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value [Not Specified]
Comments [Not Specified]
Method ANCOVA
Comments Repeated analysis of covariance heterogeneous auto-regressive w/ tx center wk & tx by wk fixed effects; Baseline HAM-D total score covariate in model.
Method of Estimation Estimation Parameter Mean Difference (Final Values)
Estimated Value -1.0
Confidence Interval 95%
-2.1 to 0.1
Estimation Comments Difference is pregabalin minus placebo.
Time Frame [Not Specified]
Adverse Event Reporting Description [Not Specified]
 
Arm/Group Title Pregabalin Placebo
Hide Arm/Group Description Pregabalin doses of 150 milligrams (mg)/day, 300 mg/day, 450 mg/day, and 600 mg/day was administered orally, twice daily (BID), with or without food, during the double-blind phase. Flexible dosing of pregabalin was allowed during the first 6 weeks; fixed dosing was required for the last 2 weeks of this period.Subjects were required to remain on a stable dose of their concurrent Generalized Anxiety Disorder (GAD) treatment (ie, escitalopram, paroxetine, or venlafaxine XR). Placebo was administrated orally, twice daily (BID) with or without food, during the double-blind phase. Subjects were required to remain on a stable dose of their concurrent GAD treatment (ie, escitalopram, paroxetine, or venlafaxine XR).
All-Cause Mortality
Pregabalin Placebo
Affected / at Risk (%) Affected / at Risk (%)
Total   --/--   --/-- 
Hide Serious Adverse Events
Pregabalin Placebo
Affected / at Risk (%) Affected / at Risk (%)
Total   1   3 
Cardiac disorders     
Cardiac failure congestive   1/180 (0.56%)  0/176 (0.00%) 
Gastrointestinal disorders     
Abdominal pain upper   0/180 (0.00%)  1/176 (0.57%) 
Infections and infestations     
Cellulitis   1/180 (0.56%)  0/176 (0.00%) 
Injury, poisoning and procedural complications     
Lower limb fracture   0/180 (0.00%)  1/176 (0.57%) 
Fall   0/180 (0.00%)  1/176 (0.57%) 
Psychiatric disorders     
Depression   0/180 (0.00%)  1/176 (0.57%) 
Respiratory, thoracic and mediastinal disorders     
Chronic Obstructive Pulmonary Disease (COPD)   1/180 (0.56%)  0/176 (0.00%) 
Indicates events were collected by systematic assessment
Hide Other (Not Including Serious) Adverse Events
Frequency Threshold for Reporting Other Adverse Events 2%
Pregabalin Placebo
Affected / at Risk (%) Affected / at Risk (%)
Total   81   59 
Eye disorders     
Vision blurred   8/180 (4.44%)  2/176 (1.14%) 
Gastrointestinal disorders     
Constipation   5/180 (2.78%)  3/176 (1.70%) 
Diarrhea   7/180 (3.89%)  7/176 (3.98%) 
Dry mouth   4/180 (2.22%)  2/176 (1.14%) 
Dyspepsia   6/180 (3.33%)  1/176 (0.57%) 
Flatulence   4/180 (2.22%)  0/176 (0.00%) 
Nausea   13/180 (7.22%)  8/176 (4.55%) 
Vomiting   2/180 (1.11%)  4/176 (2.27%) 
General disorders     
Fatigue   7/180 (3.89%)  5/176 (2.84%) 
Infections and infestations     
Nasopharyngitis   5/180 (2.78%)  6/176 (3.41%) 
Upper respiratory tract infection   3/180 (1.67%)  6/176 (3.41%) 
Investigations     
Weight increased   4/180 (2.22%)  0/176 (0.00%) 
Musculoskeletal and connective tissue disorders     
Arthralgia   5/180 (2.78%)  1/176 (0.57%) 
Nervous system disorders     
Dizziness   21/180 (11.67%)  10/176 (5.68%) 
Headache   17/180 (9.44%)  7/176 (3.98%) 
Paraesthesia   4/180 (2.22%)  1/176 (0.57%) 
Sedation   7/180 (3.89%)  7/176 (3.98%) 
Somnolence   15/180 (8.33%)  6/176 (3.41%) 
Psychiatric disorders     
Euphoric mood   4/180 (2.22%)  0/176 (0.00%) 
Insomnia   5/180 (2.78%)  1/176 (0.57%) 
Respiratory, thoracic and mediastinal disorders     
Cough   2/180 (1.11%)  6/176 (3.41%) 
Indicates events were collected by systematic assessment
Further enrollment in this study was stopped based on the recommendation of an independent Data Monitoring Committee (DMC). An interim data analysis did not suggest the potential for robust efficacy. The study was not stopped for any safety findings.
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 < 60 days. Investigator will postpone single center publications until after disclosure of pooled data (all sites), < 12 months from study completion/termination at all participating sites. Investigator may not disclose previously undisclosed confidential info other than study results.
Results Point of Contact
Layout table for Results Point of Contact information
Name/Title: Pfizer ClinicalTrials.gov Call Center
Organization: Pfizer, Inc.
Phone: 1-800-718-1021
EMail: ClinicalTrials.govCallCenter@pfizer.com
Layout table for additonal information
Responsible Party: Director, Clinical Trial Disclosure Group, Pfizer, Inc.
ClinicalTrials.gov Identifier: NCT00413010    
Other Study ID Numbers: A0081103
First Submitted: December 15, 2006
First Posted: December 19, 2006
Results First Submitted: February 27, 2009
Results First Posted: December 2, 2009
Last Update Posted: December 9, 2009