A 13-Week, Randomized, Double-Blind, Multicenter, Placebo-Controlled Study Of Pregabalin For Postherpetic Neuralgia

Study Overview
=================
Brief Summary
-----------------
The purpose of this study is to evaluate efficacy and safety of pregabalin in the treatment of postherpetic neuralgia in a dose-ranging manner.

Official Title
-----------------
A 13-Week, Randomized, Double-Blind, Multicenter, Placebo-Controlled Study To Evaluate Efficacy And Safety Of Pregabalin In The Treatment Of Postherpetic Neuralgia

Conditions
-----------------
Neuralgia, Postherpetic

Intervention / Treatment
-----------------
* Drug: Placebo
* Drug: Pregabalin
* Drug: Pregabalin
* Drug: Pregabalin


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Visual Analogue Scale (VAS) of pain is higher than 40 mm. Pain is sustained for more than 3 months after healing of herpes zoster skin rash. Exclusion Criteria: Malignancy within the past 2 years. Patients who have undergone neurolytic or neurosurgical therapy for postherpetic neuralgia. Creatinine clearance </= 30 mL/min (estimated from serum creatinine, body weight, age, and sex using the Cockcroft and Gault equation, by omitting any decimal fractions). Patients having other severe pain which may impair the self assessment of the pain due to postherpetic neuralgia. Skin conditions in the affected dermatome that could alter sensation.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Placebo<br> | Drug: Placebo<br>* placebo, oral administration for 13 weeks (1 week titration and 12-week fixed dose).<br>|
| Experimental: Pregabalin 150mg/day<br> | Drug: Pregabalin<br>* Pregabalin 150mg/day (75mg BID), oral administration for 13 weeks (1-week titration and 12-week fixed dose).<br>|
| Experimental: Pregabalin 300mg/day<br> | Drug: Pregabalin<br>* Pregabalin 300mg/day (150mg/BID), oral administration for 13 weeks (1-week titration and 12-week fixed dose).<br>|
| Experimental: Pregabalin 600mg/day<br> | Drug: Pregabalin<br>* Pregabalin 600 mg/day (300 mg/BID), oral administration for 13 weeks (1-week titration and 12-week fixed dose).<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean Pain Scores at Endpoint | Endpoint mean pain score is defined as the mean of the last 7 daily pain diary rating while taking the study medication, up to and including day after last dose. Scores range from 0-10 (11 points ordinal) with higher scores indicating increased pain. | Week13/discontinuation | 
| Mean Pain Score at Endpoint by Groups of Subjects With Expected Similar Plasma Concentrations | Endpoint mean pain score is defined as the mean of the last 7 daily pain diary rating while taking the study medication, up to and including day after last dose. Scores range from 0-10 (11 points ordinal) with higher scores indicating increased pain. | Week13/discontinuation | 
| Number of Responders | A responder is defined as a subject with a 50% reduction in weekly mean pain score from baseline to endpoint. | Week13/discontinuation | 
| Mean Pain Scores at Week 1 | Weekly mean pain score is defined as the mean of the last 7 daily diary pain ratings. Scores range from 0-10 (11 points ordinal)with higher scores indicating increased pain. | Week 1 | 
| Mean Pain Scores at Week 2 | Weekly mean pain score is defined as the mean of the last 7 daily diary pain ratings. Scores range from 0-10 (11 points ordinal)with higher scores indicating increased pain. | Week 2 | 
| Mean Pain Scores at Week 3 | Weekly mean pain score is defined as the mean of the last 7 daily diary pain ratings. Scores range from 0-10 (11 points ordinal)with higher scores indicating increased pain. | Week 3 | 
| Mean Pain Scores at Week 4 | Weekly mean pain score is defined as the mean of the last 7 daily diary pain ratings. Scores range from 0-10 (11 points ordinal)with higher scores indicating increased pain. | Week4 | 
| Mean Pain Scores at Week 5 | Weekly mean pain score is defined as the mean of the last 7 daily diary pain ratings. Scores range from 0-10 (11 points ordinal)with higher scores indicating increased pain. | Week 5 | 
| Mean Pain Scores at Week 6 | Weekly mean pain score is defined as the mean of the last 7 daily diary pain ratings. Scores range from 0-10 (11 points ordinal)with higher scores indicating increased pain. | Week 6 | 
| Mean Pain Scores at Week 7 | Weekly mean pain score is defined as the mean of the last 7 daily diary pain ratings. Scores range from 0-10 (11 points ordinal)with higher scores indicating increased pain. | Week 7 | 
| Mean Pain Scores at Week 8 | Weekly mean pain score is defined as the mean of the last 7 daily diary pain ratings. Scores range from 0-10 (11 points ordinal)with higher scores indicating increased pain. | Week 8 | 
| Mean Pain Scores at Week 9 | Weekly mean pain score is defined as the mean of the last 7 daily diary pain ratings. Scores range from 0-10 (11 points ordinal)with higher scores indicating increased pain. | Week 9 | 
| Mean Pain Scores at Week 10 | Weekly mean pain score is defined as the mean of the last 7 daily diary pain ratings. Scores range from 0-10 (11 points ordinal)with higher scores indicating increased pain. | Week 10 | 
| Mean Pain Scores at Week 11 | Weekly mean pain score is defined as the mean of the last 7 daily diary pain ratings. Scores range from 0-10 (11 points ordinal)with higher scores indicating increased pain. | Week 11 | 
| Mean Pain Scores at Week 12 | Weekly mean pain score is defined as the mean of the last 7 daily diary pain ratings. Scores range from 0-10 (11 points ordinal)with higher scores indicating increased pain. | Week 12 | 
| Mean Pain Scores at Week 13 | Weekly mean pain score is defined as the mean of the last 7 daily diary pain ratings. Scores range from 0-10 (11 points ordinal)with higher scores indicating increased pain. | Week 13 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Endpoint Sensory Scores of the Short-Form McGill Pain Questionnaire | Sensory score range from 0-33. Higher scores indicate more severe pain. | Week13/discontinuation | 
| Endpoint Affective Scores of the Short-Form McGill Pain Questionnaire | Affective score range from 0-12. Higher scores indicate more severe pain. | Week13/discontinuation | 
| Endpoint Total Scores of the Short-Form McGill Pain Questionnaire | Total score range from 0-45. Higher scores indicate more severe pain. | Week13/discontinuation | 
| Endpoint Visual Analogue Scale Scores of the Short-Form McGill Pain Questionnaire | Visual Analogue Scale Score range from 0-100mm. Higher scores indicate more severe pain. | Week13/discontinuation | 
| Endpoint Present Pain Intensity Scores of the Short-Form McGill Pain Questionnaire | Present pain intensity score range from 0-5. Higher scores indicate more severe pain. | Week13/discontinuation | 
| Mean Sleep Interference Scores at Endpoint | Scores range from 0-10. Higher scores indicate more severe interference with sleep. | Week13/discontinuation | 
| Endpoint Medical Outcomes Study Sleep Scale Scores:Sleep Disturbance | Score range for sleep disturbance is 0-100.Higher scores indicate more of the attribute. | Week13/discontinuation | 
| Endpoint Medical Outcomes Study Sleep Scale Scores:Snoring | Score range for snoring is 0-100.Higher scores indicate more of the attribute. | Week13/discontinuation | 
| Endpoint Medical Outcomes Study Sleep Scale Scores:Awaken Short of Breath or With Headache | Score range for awaken short of breath or with headache is 0-100. Higher scores indicate more of the attribute. | Week13/discontinuation | 
| Endpoint Medical Outcomes Study Sleep Scale Scores:Quantity of Sleep | Sleep Quantity subscale is scored from 0-24 indicating the number of hours of sleep. Higher scores indicate more of the attribute named in the subscale. | Week13/discontinuation | 
| Endpoint Medical Outcomes Study Sleep Scale Scores:Sleep Adequacy | Score range for sleep adequacy is 0-100. Higher scores indicate more of the attribute. | Week13/discontinuation | 
| Endpoint Medical Outcomes Study Sleep Scale Scores:Somnolence | Score range for Somnolence is 0-100. Higher scores indicate more of the attribute. | Week13/discontinuation | 
| Endpoint Medical Outcomes Study Sleep Scale Scores:Overall Sleep Problem Index | Score range for overall sleep problem index is 0-100. Higher scores indicate more of the attribute. | Week13/discontinuation | 
| Endpoint Medical Outcomes Study Sleep Scale: Number of Participants With Optimal Sleep | Number of participants who reported Optimal Sleep | Week13/discontinuation | 
| Endpoint Patient Global Impression Change | Patient Global Impression Change is scaled from 1 to 7. 1=very much improved, 7=very much worse. | Week13/discontinuation | 
| Endpoint Clinical Global Impression Change | Clinical Global Impression Change is scaled from 1 to 7. 1=very much improved, 7=very much worse. | Week13/discontinuation | 
| Endpoint Short-Form 36-Item Health Survey Scores: Physical Functioning | Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. | Week13/discontinuation | 
| Endpoint Short-Form 36-Item Health Survey Scores: Role Limitations-Physical | Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. | Week13/discontinuation | 
| Endpoint Short-Form 36-Item Health Survey Scores: Bodily Pain | Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. | Week13/discontinuation | 
| Endpoint Short-Form 36-Item Health Survey Scores: General Health Perception | Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. | Week13/discontinuation | 
| Endpoint Short-Form 36-Item Health Survey Scores: Social Functioning | Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. | Week13/discontinuation | 
| Endpoint Short-Form 36-Item Health Survey Scores: Role Limitations-Emotional | Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. | Week13/discontinuation | 
| Endpoint Short-Form 36-Item Health Survey Scores: Vitality | Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. | Week13/discontinuation | 
| Endpoint Short-Form 36-Item Health Survey Scores: Mental Health | Short-Form 36-Item Health Survey is scored from 0-100 with higher scores reflecting better patient status. | Week13/discontinuation | 
| Number of Patients Not Reporting Allodynia | Participants not reporting allodynia. | Week13/discontinuation | 
| Number of Patients Not Reporting Hyperalgesia | Participants not reporting hyperalgesia. | Week13/discontinuation | 
| Mean Sleep Interference Scores at Week 1 | Weekly mean sleep interference scores is defined as the mean of the last 7 daily diary interference with sleep ratings. Scores range from 0-10 (11 points ordinal) with higher scores indicating more severe interference with sleep. | week 1 | 
| Mean Sleep Interference Scores at Week 2 | Weekly mean sleep interference scores is defined as the mean of the last 7 daily diary interference with sleep ratings. Scores range from 0-10 (11 points ordinal) with higher scores indicating more severe interference with sleep. | week 2 | 
| Mean Sleep Interference Scores at Week 3 | Weekly mean sleep interference scores is defined as the mean of the last 7 daily diary interference with sleep ratings. Scores range from 0-10 (11 points ordinal) with higher scores indicating more severe interference with sleep. | week 3 | 
| Mean Sleep Interference Scores at Week 4 | Weekly mean sleep interference scores is defined as the mean of the last 7 daily diary interference with sleep ratings. Scores range from 0-10 (11 points ordinal) with higher scores indicating more severe interference with sleep. | week 4 | 
| Mean Sleep Interference Scores at Week 5 | Weekly mean sleep interference scores is defined as the mean of the last 7 daily diary interference with sleep ratings. Scores range from 0-10 (11 points ordinal) with higher scores indicating more severe interference with sleep. | week 5 | 
| Mean Sleep Interference Scores at Week 6 | Weekly mean sleep interference scores is defined as the mean of the last 7 daily diary interference with sleep ratings. Scores range from 0-10 (11 points ordinal) with higher scores indicating more severe interference with sleep. | week 6 | 
| Mean Sleep Interference Scores at Week 7 | Weekly mean sleep interference scores is defined as the mean of the last 7 daily diary interference with sleep ratings. Scores range from 0-10 (11 points ordinal) with higher scores indicating more severe interference with sleep. | week 7 | 
| Mean Sleep Interference Scores at Week 8 | Weekly mean sleep interference scores is defined as the mean of the last 7 daily diary interference with sleep ratings. Scores range from 0-10 (11 points ordinal) with higher scores indicating more severe interference with sleep. | week 8 | 
| Mean Sleep Interference Scores at Week 9 | Weekly mean sleep interference scores is defined as the mean of the last 7 daily diary interference with sleep ratings. Scores range from 0-10 (11 points ordinal) with higher scores indicating more severe interference with sleep. | week 9 | 
| Mean Sleep Interference Scores at Week 10 | Weekly mean sleep interference scores is defined as the mean of the last 7 daily diary interference with sleep ratings. Scores range from 0-10 (11 points ordinal) with higher scores indicating more severe interference with sleep. | week 10 | 
| Mean Sleep Interference Scores at Week 11 | Weekly mean sleep interference scores is defined as the mean of the last 7 daily diary interference with sleep ratings. Scores range from 0-10 (11 points ordinal) with higher scores indicating more severe interference with sleep. | week 11 | 
| Mean Sleep Interference Scores at Week 12 | Weekly mean sleep interference scores is defined as the mean of the last 7 daily diary interference with sleep ratings. Scores range from 0-10 (11 points ordinal) with higher scores indicating more severe interference with sleep. | week 12 | 
| Mean Sleep Interference Scores at Week 13 | Weekly mean sleep interference scores is defined as the mean of the last 7 daily diary interference with sleep ratings. Scores range from 0-10 (11 points ordinal) with higher scores indicating more severe interference with sleep. | week 13 |