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CompletedNCT00567814Updated Sep 18, 2026Results posted

A Placebo-Controlled Study of a Combination of Metyrapone and Oxazepam in Cocaine Addiction

An interventional study of Metyrapone and Oxazepam in Cocaine Dependence and Cocaine Addiction, sponsored by Embera NeuroTherapeutics, Inc.. Completed at 1 site in United States. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-09-18.

Sponsored by Embera NeuroTherapeutics, Inc. · Not applicable, Interventional, and Treatment

Phase
Not applicable
Study type
Interventional
Enrollment
45
Allocation
Randomized
Ages
18 Years to 65 Years
Sex
All
01

Study summary

Subjects will be randomly assigned to receive either one of the two potential dose combinations of the study medications or placebo over 6 weeks. The study will include twice weekly visits to the research clinic for laboratory studies, safety assessments and urine drug screens. Subjects will also be questioned regarding drug craving and mood symptoms.

02

Conditions studied

  • Cocaine Dependence
  • Cocaine Addiction

Keywords

  • Cocaine
  • Dependence
  • Addiction
  • Cortisol
  • GABA
03

Who can participate

Ages eligible
18 Years to 65 Years
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • Male or female, 18 - 50 years of age
  • Requests treatment for cocaine addiction
  • Meets the DSM-IV criteria for cocaine dependency
  • Able to provide written informed consent and comply with the study
  • Females of childbearing potential must have a negative pregnancy test and must be using adequate birth control during the study
  • Test positive for cocaine on a urinary drug screen
  • Healthy and medically stable in the opinion of the Principal Investigator

Exclusion criteria

Exclusion Criteria:

  • Liver enzymes greater than two times normal
  • Any history of hepatitis
  • History of disorders requiring chronic treatment with steroids
  • Significantly abnormal ECG
  • Any prominent DSM-IV axis I disorders other than cocaine dependence
  • Any subject who presents as a danger to self or others in the opinion of the Principal Investigator
  • Concomitant use of methamphetamine as determined by self-reporting and verified by measurement of methamphetamine in urinary drug screen
  • Alcohol consumption greater than 4 drinks per day (1 Drink = 12 oz beer; 5 oz wine; 1.5 oz shot of liquor)
  • Any clinically significant laboratory test abnormalities
  • Use of any concomitant medication during the study that would interfere with study medications
  • Serum cortisol less than 3 µg/dl at any time before or during study
  • Treatment with an investigational product within 30 days prior to study enrollment
  • Currently seeking other forms of professional addiction treatment
  • Known allergic reaction to oxazepam or metyrapone
  • Lactose intolerance
04

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
45 participants (actual)

Study arms

  • Active comparator
    Metyrapone 500 mg oxazepam 20 mg

    Lower dose combination of metyrapone with oxazepam, total daily dose

    Drug: Metyrapone · Drug: Oxazepam

  • Active comparator
    Metyrapone 1500 mg oxazepam 20 mg

    Higher dose combination of metyrapone with oxazepam, total daily dose

    Drug: Metyrapone · Drug: Oxazepam

  • Placebo comparator
    Placebo

    Placebo

    Drug: Placebo

Interventions

  • DrugMetyrapone

    Twice daily

    Also known as: Metopirone

  • DrugOxazepam

    Twice Daily

    Also known as: Serax

  • DrugPlacebo

    Twice daily

05

What researchers measure

Primary outcomes

  1. Change in Cocaine Craving Questionnaire Brief

    The Cocaine Craving Questionnaire Brief (CCQ-Brief) is an abbreviated version of the CCQ-Now that includes ten items (CCQ-Now includes 45 items). The scale measures cocaine craving symptoms. The 10 items are scored on a one to seven scale with 8 positively-keyed items and two negatively-keyed items. The score is the sum of the individual items divided by 10 (lowest possible score, indicating lowest level of cocaine craving) is 1 and highest possible total score (indicating the highest level of cocaine craving, is 10). There are no subscores.

    Time frame: Week 1, Day 3 to Week 6, day 3

06

Results

Posted Sep 18, 2026

Participant flow

Participant flow — Overall Study
MilestoneMetyrapone 500 mg Oxazepam 20 mgMetyrapone 1500 mg Oxazepam 20 mgPlacebo
Started151515
Efficacy evaluable989
Completed679
Not completed986

Outcome measures

PrimaryChange in Cocaine Craving Questionnaire Brief

The Cocaine Craving Questionnaire Brief (CCQ-Brief) is an abbreviated version of the CCQ-Now that includes ten items (CCQ-Now includes 45 items). The scale measures cocaine craving symptoms. The 10 items are scored on a one to seven scale with 8 positively-keyed items and two negatively-keyed items. The score is the sum of the individual items divided by 10 (lowest possible score, indicating lowest level of cocaine craving) is 1 and highest possible total score (indicating the highest level of cocaine craving, is 10). There are no subscores.

Time frame:
Week 1, Day 3 to Week 6, day 3
Reported as:
Mean · Change in scores on scale
Change in Cocaine Craving Questionnaire Brief
Change in scores on scaleMetyrapone 500 mg Oxazepam 20 mgMetyrapone 1500 mg Oxazepam 20 mgPlacebo
Change in Cocaine Craving Questionnaire Brief-0.5 ± 0.74-0.8 ± 1.34-0.6 ± 1.16

Adverse events

Collected over With an onset date after first administration of study treatment will be collected through the follow-up visit (up to 7 weeks). Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Metyrapone 500 mg Oxazepam 20 mg0/15 (0%)0/15 (0%)15/15 (100%)
Metyrapone 1500 mg Oxazepam 20 mg0/15 (0%)0/15 (0%)15/15 (100%)
Placebo0/15 (0%)0/15 (0%)15/15 (100%)
Most frequent other events
Showing 10 of 75
Most frequent other events
EventMetyrapone 500 mg Oxazepam 20 mgMetyrapone 1500 mg Oxazepam 20 mgPlacebo
HeadacheNervous system disorders5/152/153/15
NauseaGastrointestinal disorders4/154/151/15
IrritabilityGeneral disorders2/154/151/15
SomnolencePsychiatric disorders4/152/152/15
InsomniaNervous system disorders3/150/150/15
DiarrhoeaGastrointestinal disorders2/150/153/15
Abdominal pain upperGastrointestinal disorders0/151/153/15
ToothacheGastrointestinal disorders1/152/150/15
Dry mouthGastrointestinal disorders2/152/152/15
VomitingGastrointestinal disorders1/150/152/15

Baseline characteristics

Safety population

Age, Continuous
Age, Continuous(year)Metyrapone 500mg Oxazepam 20mgMetyrapone 1500 mg Oxazepam 20 mgPlaceboTotal
Mean39.7 ± 8.839.5 ± 7.7439.3 ± 8.139.5 ± 8.04
Sex: Female, Male
Sex: Female, Male(Participants)Metyrapone 500mg Oxazepam 20mgMetyrapone 1500 mg Oxazepam 20 mgPlaceboTotal
Female36514
Male1291031
Race (NIH/OMB)
Race (NIH/OMB)(Participants)Metyrapone 500mg Oxazepam 20mgMetyrapone 1500 mg Oxazepam 20 mgPlaceboTotal
American Indian or Alaska Native0000
Asian0000
Native Hawaiian or Other Pacific Islander0000
Black or African American810725
White75820
More than one race0000
Unknown or Not Reported0000
Region of Enrollment
Region of Enrollment(Participants)Metyrapone 500mg Oxazepam 20mgMetyrapone 1500 mg Oxazepam 20 mgPlaceboTotal
United States15151545
Cocaine use in years
Cocaine use in years(Years)Metyrapone 500mg Oxazepam 20mgMetyrapone 1500 mg Oxazepam 20 mgPlaceboTotal
Mean13.1 ± 7.214.1 ± 10.2213.9 ± 12.513.7 ± 8.21
Cocaine use per week
Cocaine use per week(Events per week)Metyrapone 500mg Oxazepam 20mgMetyrapone 1500 mg Oxazepam 20 mgPlaceboTotal
Mean4 ± 2.122.3 ± 2.054.2 ± 2.333.5 ± 3
07

Study locations

1 site
  • Department of Psychiatry, Psychopharmacology Research Clinic
    Shreveport, Louisiana 71103, United States
08

Registry details

Key details

Study ID
NCT00567814
Lead sponsor
Embera NeuroTherapeutics, Inc.
Responsible party
Sponsor
First posted
Dec 5, 2007
Start date
Dec 2007
Primary completion
Nov 2008
Completion
Nov 2008
Results posted
Sep 18, 2026
Last update
Sep 18, 2026

Study contacts

Anita S Kablinger, MD
principal investigator · LSU Health Sciences Center - Shreveport

Oversight

Data monitoring committee
No
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