Clinical Trial: Safety and Efficacy of Gabapentin in Postherpetic Neuralgia

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: A Phase 3 Multicenter, Randomized, Double-Blind, Placebo-Controlled Study of the Safety and Efficacy of Gabapentin Extended Release (G-ER) Tablets in the Treatment of Patients With The primary study objective is to assess the relative efficacy of G-ER dosed once daily (1800 mg following the evening meal), versus placebo in reducing the mean daily pain score from the baseline week to the end of the efficacy treatment period (Treatment Week 10) in patients with PHN.

Secondary efficacy measures will include changes from baseline in mean weekly sleep interference scores, Short-Form McGill Pain Questionnaire (SF-MPQ), the Neuropathic Pain Scale (NPS), Brief Pain Inventory (BPI), Patient Global Impression of Change (PGIC), and Investigator-Rated Clinical Global Impression of Change (CGIC).


Sponsor: Depomed

Current Primary Outcome: Mean Change in Baseline Observation Carried Forward (BOCF) Average Daily Pain Score [ Time Frame: 10 weeks ]

Average daily pain scored on 11-point numerical rating scale (where 0 = no pain, 10 = worst possible pain). Results presented as least squares (LS) mean change in baseline observation carried forward (BOCF) average daily pain score from baseline to the final week of efficacy treatment period (Week 10).


Original Primary Outcome:

  • The primary study objective is to assess the relative efficacy of G-ER vs. placebo in reducing the average daily pain score from the baseline week to the final week of the efficacy treatment period (Treatment Week 10) in patients with PHN.
  • Daily pain scores will be measured using a electronic diary.


Current Secondary Outcome:

  • Patient Global Impression of Change (PGIC) [ Time Frame: 10 weeks ]
    Patient self-assessment of how much pain had changed at end of treatment period (Week 10) compared to pain at baseline; scored on 7-point numerical rating scale (where 1 = very much improved, 7 = very much worse). Results presented as number of participants categorized at end of treatment (Week 10) as "very much improved" (score = 1) or "much improved" (score = 2).
  • Clinical Global Impression of Change (CGIC) [ Time Frame: 10 weeks ]
    Investigator assessment of patient's overall PHN symptoms at end of treatment period (Week 10) compared to overall PHN symptoms at baseline; scored on 7-point numerical rating scale (where 1 = very much improved, 7 = very much worse). Results presented as number of participants categorized at end of treatment (Week 10) as "very much improved" (score = 1) or "much improved" (score = 2).
  • Average Daily Sleep Interference Score [ Time Frame: 10 weeks ]
    Assessed on 11-point numeric rating scale (where 0 = pain does not interfere with sleep, 10 = pain completely interferes with sleep); evaluated from daily sleep entry in electronic diary. Results presented as least squares (LS) mean change in baseline observation carried forward (BOCF) average daily sleep interference score from baseline to final week of treatment period (Week 10).


Original Secondary Outcome: Same as current

Information By: Depomed

Dates:
Date Received: June 8, 2006
Date Started: May 2006
Date Completion:
Last Updated: February 21, 2012
Last Verified: February 2012