Modified-release formulation of morphine sulfate for neuropathic pain after spinal cord injury
Principal Investigator Name
Thomas N. Bryce M.D.
Principal Investigator Email
individuals with traumatic or non-traumatic SCI and moderate or severe neuropathic pain
Four out of five persons with SCI report chronic pain, while one-third report chronic severe pain that interferes with activity and affects quality of life. In three-fourths of cases this pain is neuropathic in nature, a pain type that has not been found to be amenable to treatment in many cases. There is evidence supporting the efficacy of opioids in the treatment of neuropathic pain in persons without SCI. However, evidence for the effectiveness of this class of drugs in individuals with SCI is limited. The intractable nature of neuropathic pain is most evident when the pain is at-level central pain (ALCP), at-level radicular pain (ALRP), and below-level central pain (BLCP).
This project is a double-blinded randomized placebo-controlled two-phase (14-week) crossover trial of modified-release morphine, an opioid, added to the existing non-opioid pain medication regimen that previously has been prescribed for subjects. Individuals with traumatic and non-traumatic SCI, including multiple sclerosis, who have moderate or severe pain (4 or higher on a 0-10 Numeric Rating Scale) in spite of non-opioid medications and other pain interventions are eligible. Primary outcome measures are pain severity (average of daily ratings over 14 days using a 0-10 Numeric Rating Scale [NRS]); secondary outcomes are medication quantity effective for analgesia (maximum: 120 mg per day) or maximally tolerated; concomitant medication; adverse events; Short McGill Pain Questionnaire (modified); morphine cognitive effects scale; Patient Generated Index for activity, Multidimensional Pain Inventory Life Interference subscale; Brief Patient Health Questionnaire; Expanded Disability Status Scale (EDSS) Questionnaire (for Multiple Sclerosis subjects), Positive And Negative Affect Schedule; Short-Form 36; subject global impression of change; static and dynamic allodynia (determined using quantitative sensory testing); and daily number of paroxysmal pains.
Outcomes will be assessed separately for ALCP, ALRP and BLCP. Over five years, 16 subjects in each group will be entered into the trial; this number is expected to be sufficient to demonstrate a 1.75 average NRS pain severity decrease. Changes in primary and secondary outcomes will be analyzed using repeated measures analysis of variance.