NCT01189097

Combined Therapy of Methadone and Dextromethrophan

Combined Therapy of Methadone and Dextromethrophan: A Novel Strategy for the Treatment of Opioid Dependence

• Status: Unknown
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 1,500 (estimated)
• Sponsor: National Cheng-Kung University Hospital · Academic / Other
• Sex: All
• Age: 18 Years – 65 Years
• Healthy volunteers: Not accepted

Summary

The purpose of this study is to determine the pharmacological effects and outcomes of DM therapy with this add-on study. And to determine the immunological changes between the baseline and the end point of the study.

Detailed description

Opioid dependence is a severe public health problem. Current efforts to taper individuals off opioid medications are limited due to a high relapse rate and lack of efficacy in relieving subjective symptoms. Methadone substitution therapies might decrease the criminal rate and increase the quality of life for individuals with opioid dependence, but the high drop-out rate and continuing use of methadone are major problems in the maintenance of therapy for opioid dependence. Studies in the pathogenesis of opioid dependence and additional behaviors need more focused attention. Dextromethorphan (DM) is a noncompetitive N-methyl-D-aspartate receptor antagonist that has proven safety record for anti-tussive purpose. Previous studies demonstrated that DM may be useful in decreasing craving in animals (Huang, et al., 2003; Lue et al., 2007) and withdrawal tendencies in human with opioid dependence. In recent studies, DM has been reported to afford neuroprotection against endotoxin-induced dopaminergic neurotoxicity (Li et al. 2005; Liu et al. 2003; Zhang et al. 2004, 2005) which might be related to treatment for additictive behaviors. The purposes of this study are to examine whether DM is able to 1) reduce opioid tolerance and decrease methadone use; 2) reduce withdrawal symptoms; 3) decrease the relapse rate of opioid use, and 4) be an effective treatment for opioid dependence (and addictive behaviors). This is a double-blinded, placebo-controlled, randomized, and parallel groups clinical research trial study. Subjects with opioid dependence are recruited from two different sources. One group will come from the list of current opioid users and will be required to stay on methadone treatment (opioid using group), and the second group will come from subjects who are forced to discontinue opioid use for more than one week (opioid free group). In the opioid using group, add-on of DM or placebo treatment will proceed in a double-blind fashion for 12 weeks after completed structured diagnostic interview and adjusted methadone dose. In the opioid free group, subjects will take one-week placebo for the wash-out period first and then will be admitted into a double-blind DM/placebo only for 12 weeks. Both opioid using and opioid free groups will be examined weekly through urine tests for opioid use and will be assessed on a craving scale after the completion of the structured diagnostic interviews. We will measure the treatment response and side effects to clarify the curative effects of DM with the use of the double-blinded DM/placebo therapy design in both the opioid using and opioid free groups. Several psychological examinations, psychosocial questionnaires, tests for immune parameters, electrophysiological studies and genetic markers will be performed in this study. The interim analysis and decording of partial subjects who completed DM/placebo add-on treatment for three months will be performed in the end of first year.

Conditions

• Opioid Abuse

Interventions

Type	Name	Description
DRUG	Dextromethorphan	Subjects who have not used opioid for at least one week before baseline evaluation will take one-week placebo for the wash-out period first and then will be categorized into the opioid free group. The subjects of the opioid using group will be assigned randomly into the following six groups: 1) Methadone + DM 60mg; 2) Methadone + DM 120mg; 3) Methadone + Placebo; 4) Methadone + DM 60mg + motivation and cognitive behavior therapy; 5) Methadone + DM 120mg + motivation and cognitive behavior therapy; 6) Methadone + Placebo + motivation and cognitive behavior therapy. The opioid free group will be 1) DM 30mg; 2) DM 60 mg; 3) Placebo.
DRUG	Dextromethorphan	Subjects who have not used opioid for at least one week before baseline evaluation will take one-week placebo for the wash-out period and then randomly assigned into six groups: 1) Methadone + DM 60mg; 2) Methadone + DM 120mg; 3) Methadone + Placebo; 4) Methadone + DM 60mg + motivation and cognitive behavior therapy; 5) Methadone + DM 120mg + motivation and cognitive behavior therapy; 6) Methadone + Placebo + motivation and cognitive behavior therapy. The opioid free group will be 1) DM 30mg; 2) DM 60 mg; 3) Placebo. If the subjects of the opioid free group suffer from relapses and begin to use heroin, they will receive methadone treatment. The dosage of methadone will be increased or decreased maximal 5 mg each time as necessary.

Timeline

• Start date: 2008-04-01
• Primary completion: 2011-03-01
• Completion: 2011-09-01
• First posted: 2010-08-26
• Last updated: 2010-08-26

Locations

1 site across 1 country: Taiwan