Clinical Trial: Safety and Efficacy Study of Ethosuximide for the Treatment of Complex Regional Pain Syndrome (CRPS)

Study Status: Terminated
Recruit Status: Terminated
Study Type: Interventional

Official Title: A Single Centre. Parallel-Group, Double-Blinded, Randomized, Placebo-Controlled Pilot Clinical Trial on Ethosuximide for the Treatment of Complex Regional Pain Syndrome (C

Brief Summary: Pain remains the most debilitating symptom for adult patients suffering from complex regional pain syndrome (CRPS). Most CRPS patients gain little to no relief from current painkillers. The purpose of this study is to evaluate the efficacy and safety of ethosuximide in search of much-needed adjunctive therapy to relieve the pain and suffering associated with CRPS.

Detailed Summary:

This is a single centre, parallel-group, double-blind, randomized, placebo-controlled pilot clinical trial for adults suffering from complex regional pain syndrome (CRPS).

Twelve (12) subjects diagnosed with CRPS will be enrolled and randomized to receive orally, either ethosuximide or placebo. If the maximum trial medication dosage (1500mg) is reached, the subject will be in the study for a maximum of 10 weeks from screening (Clinic Visit 1) to the end of the drug cessation period. The minimum period a subject could complete the study would be 4 weeks presuming they were not previously on any disallowed drugs and only found the 500mg dose tolerable.


Sponsor: McGill University Health Center

Current Primary Outcome: Maximum tolerated dose (500mg-1500mg per day) and Safety profile [ Time Frame: up to 10 weeks ]

Primary outcomes will consist of the dose attained during the study and the safety (adverse event) profile. Maximum timeframe on study drug is 6 weeks. Adverse events will be collected up to one month after the trial period ends.


Original Primary Outcome: Maximum tolerated dose (500mg-1500mg per day) and Safety profile [ Time Frame: Throughout the study: After disallowed drug cessation period ]

Current Secondary Outcome:

  • Pain Intensity Scores on the Visual Analogue Scale (VAS) [ Time Frame: up to 7 weeks ]
    Pain Intensity captured on Day 1 (First study visit post-disallowed drug cessation period) and 7 days after maximal-tolerated dose attained (Final Study Visit)
  • Pain Intensity Scores on the Numerical Rating Scale (NRS) [ Time Frame: up to 5 weeks ]
    Pain Intensity using the Numerical Rating Scale will be captured by telephone every week during dose titration period (Days 3 and 6).
  • Neuropathic Pain Symptom Inventory (NPSI) [ Time Frame: up to 7 weeks ]
    Day 1 (First study visit post-disallowed drug cessation period) and 7 days after maximal-tolerated dose attained (Final Study Visit)
  • Short Form 12v2 (SF-12v2) [ Time Frame: up to 7 weeks ]
    Quality of Life measured on Day 1 (First study visit post-disallowed drug cessation period) and 7 days after maximal-tolerated dose attained (Final Study Visit)
  • Short Form McGill Pain Questionnaire (SF-MPQ) [ Time Frame: up to 7 weeks ]
    Day 1 (First study visit post-disallowed drug cessation period) and 7 days after maximal-tolerated dose attained (Final Study Visit)


Original Secondary Outcome:

  • Efficacy: Pain Intensity - Visual Analogue Scale (VAS) [ Time Frame: Day 1 (First study visit post-disallowed drug cessation period) and 7 days after maximal-tolerated dose attained (Final Study Visit) ]
  • Efficacy: Pain Intensity - Numerical Rating Scale (NRS) [ Time Frame: Every week during dose titration period (Days 3 and 6) and 30 days after final study visit. ]
  • Efficacy: Pain Quality - Neuropathic Pain Symptom Inventory (NPSI) and Short Form McGill Pain Questionnaire (SF-MPQ) [ Time Frame: Day 1 (First study visit post-disallowed drug cessation period) and 7 days after maximal-tolerated dose attained (Final Study Visit) ]
  • Efficacy: Quality of Life - Short Form 12v2 (SF-12v2) [ Time Frame: Day 1 (First study visit post-disallowed drug cessation period) and 7 days after maximal-tolerated dose attained (Final Study Visit) ]


Information By: McGill University Health Center

Dates:
Date Received: May 29, 2008
Date Started: September 2008
Date Completion:
Last Updated: May 11, 2011
Last Verified: May 2011