Polyneuropathy
Conditions
Keywords
polyneuropathy, neuropathic pain, treatment
Brief summary
Polyneuropathy of different etiologies is often associated with pain and the standard treatment for this type of pain is gabapentinoids or antidepressants. The hypothesis of this study is that the combination of the gabapentinoid pregabalin and the antidepressant imipramine will provide better pain relief than the single compounds alone. This is a randomized, placebo-controlled, double-blind, 4-way, cross-over trial of pregabalin 300 mg/day, imipramine 75 mg/day and their combination versus placebo. The study will include 60 patients and the treatment outcome will be pain intensity as measured by numeric rating scales.
Interventions
DRUGImipramine
Tablet 25 mg, 3 tablets evening (extensive metabolizers) or 1 tablet evening (poor metabolizers), daily, 5 weeks
DRUGPregabalin
Capsule 75 mg, 2 capsules twice daily, daily, 5 weeks
DRUGImipramine, pregabalin
Imipramine: tablet 25 mg, 3 tablets evening (extensive metabolizers) or 1 tablet evening (poor metabolizers), daily, 5 weeks Pregabalin: capsule 75 mg, 2 capsules twice daily, daily, 5 weeks
DRUGPlacebo
Placebo tablets to imipramine 25 mg, 3 or 1 tablet evening, daily, 5 weeks Placebo capsules to pregabalin 75 mg, 2 capsules daily, daily, 5 weeks
Sponsors
Pfizer
Nycomed
Odense University Hospital
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
20 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
* Age between 20 - 85 years. * Characteristic symptoms of polyneuropathy for at least 6 months. * Polyneuropathy diagnosis confirmed by typical clinical signs (distal sensory disturbance/lack of distal deep tendon reflexes) and/or electrophysiological tests and/or abnormal quantitative sensory tests. * Total pain intensity rating of at least 4 on a 0-10 points numeric rating scale. * Pain present at least 4 days a week. * For diabetics: diabetes diagnosis for at least 6 months and stable metabolic control for at least 3 months. * For other secondary polyneuropathies: stable for at least 6 months. * For fertile females: adequate anticonceptive treatment. * Written informed consent.
Exclusion criteria
* Other cause of pain. * Contraindications against imipramine. * Allergic reactions towards imipramine or pregabalin. * Known adverse reactions during imipramine or pregabalin treatment. * Pregnancy. * Severe systemic disease. * Ongoing treatment with antidepressants, antipsychotics, anticonvulsants, opioids, propranolol, kinidine, monoamine oxidase inhibitor. * Inability to follow study protocol.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Total pain intensity as measured by numeric rating scale 0-10 points. | Median of ratings from last week of each treatment period |
Secondary
| Measure | Time frame |
|---|---|
| Specific pain symptom rated by numeric rating scales 0-10 points | Median of ratings from last week of each treatment period |
| Rating of evoked pains symptoms (pressure, brush, repetitive pin-prick, cold) as measured by numeric rating scales 0-10 points | End of each treatment period |
| Sleep disturbance as measured by numeric rating scale 0-10 points | Median of ratings from last week of each treatment period |
| Verbal pain relief scale with 6 classes | End of each treatment period |
| Health related quality of life (SF-36) | End of each treatment period |
| Major Depression Inventory (MDI) | End of each treament period |
| Consumption of escape medication (number of tablets of paracetamol) | Total consumption during last week of each treatment period |
Countries
Denmark
Contacts
Primary ContactSøren H. Sindrup, MD
Backup ContactJakob V. Holbech, MD
Outcome results
None listed