Effects of Venlafaxine on Chronic Neuropathic Pain Following Spinal Cord Injury

Sponsor

US Department of Veterans Affairs (U.S. Fed)

Overall Status

Completed

CT.gov ID

NCT00167856

Collaborator

(none)

Enrollment

Location

Arms

Duration (Months)

0.4

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The purpose of this study is to evaluate the pain-relieving effects of venlafaxine hydrochloride (Effexor) in chronic neuropathic (burning, shock-like, electric) pain after spinal cord injury (SCI). Although a number of medications have been used to treat SCI pain, no drug has been consistently helpful, and, therefore, many people with SCI continue to have difficult chronic pain. Venlafaxine is a new anti-depressant drug that has not been tested for use in SCI neuropathic pain, but has been helpful for other types of neuropathic pain.

Condition or Disease	Intervention/Treatment	Phase
Neuropathic Pain Pain Spinal Cord Injuries	Drug: Venalafaxine hydrochloride	N/A

Detailed Description

Persistent pain is one of the most common reasons for impaired quality of life following spinal cord injury (SCI). Although numerous interventions are often used to manage neuropathic pain following SCI, most people receive inadequate relief and continue to suffer many years after the original injury. The long-term goal of our pain research is to improve the management of chronic neuropathic pain following SCI.

This study examines the effect of Venlafaxine hydrochloride (VH) in the treatment of chronic neuropathic pain associated with SCI. VH is a second-generation, structurally novel antidepressant medication with a mild side-effect profile compared to these older tricyclic antidepressants (e.g. imipramine and amitriptyline). Previous clinical trials suggest that approximately 60-70% of people with heterogeneous neuropathic pain report at least moderate reductions in pain with older antidepressants. However, reported side-effects have been numerous, and few trials have been conducted on neuropathic pain due to SCI.

The current study is a two-period, 24-week crossover, randomized, placebo-controlled trial. A sample of 60 persons with chronic neuropathic pain and SCI will be randomly assigned to either of two treatment groups (n=30 for each group), in a double-blind fashion. One group will receive VH first and then placebo, whereas the second group will start with the placebo followed by the VH. There will be weekly contacts between the research staff and the study participants to assess pain relief and medication side effects (presence and severity). Several measures of pain intensity, psychosocial well-being, quality of life, and sensory function will be taken throughout the study to examine the effects of VH on neuropathic pain.

We expect that VH will help to relieve neuropathic pain in persons with SCI, and that this decrease in pain intensity will correlate with a reduced psychosocial impact, improved mood, increased participation in daily activities, and increased life satisfaction.

Study Design

Study Type:

Interventional

Actual Enrollment :

16 participants

Allocation:

Randomized

Intervention Model:

Crossover Assignment

Masking:

Triple (Participant, Care Provider, Investigator)

Primary Purpose:

Treatment

Official Title:

Effects of Venlafaxine on Chronic Neuropathic Pain Following Spinal Cord Injury

Study Start Date :

Jun 1, 2005

Actual Primary Completion Date :

Aug 1, 2007

Actual Study Completion Date :

Aug 1, 2008

Arms and Interventions

Arm	Intervention/Treatment
Experimental: 1 Venlafaxine HCL (extended release)	Drug: Venalafaxine hydrochloride Norepinephrine/Serotonin Reuptake Inhibitor (NSRI) Other Names: Effexor XR
Active Comparator: 2 Benztropine Mesylate	Drug: Venalafaxine hydrochloride Norepinephrine/Serotonin Reuptake Inhibitor (NSRI) Other Names: Effexor XR

Arm

Intervention/Treatment

Experimental: 1

Venlafaxine HCL (extended release)

Drug: Venalafaxine hydrochloride

Norepinephrine/Serotonin Reuptake Inhibitor (NSRI)

Other Names:

Effexor XR

Active Comparator: 2

Benztropine Mesylate

Drug: Venalafaxine hydrochloride

Norepinephrine/Serotonin Reuptake Inhibitor (NSRI)

Other Names:

Effexor XR

Outcome Measures

Primary Outcome Measures

Pain Intensity as measured by subject pain diaries [Baseline (2 Weeks); Phase 1 (1 week at max dose); Washout (2 weeks); Phase 2 (1 week at max dose)]

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 70 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

participant must be able to swallow pills
fluent in English
incomplete or complete spinal cord injury
presence of at least moderately severe neuropathic pain at or below the level of injury
spinal cord injury at least 2 year prior to entering the study
pain for at least 6 months prior to entering the study
spinal cord injury level above L1
participants on anticonvulsants are considered
approval of primary physician

Exclusion Criteria:

pregnant women, or those contemplating pregnancy
prior history of use of Venlafaxine hydrochloride (Effexor)
current use of MAOI medications
persons who have a recent (past year) history of alcohol or drug abuse
persons with a history of renal disease, heart disease or uncontrolled hypertension, liver disease or hepatic cirrhosis, active major medical or psychiatric illness
persons with a significant post-traumatic encephalopathy from head trauma sustained at SCI
persons with tardive dyskinesia or narrow angle glaucoma