CClinicalTrials.gg
CompletedNCT04501874Updated Sep 21, 2026Results posted

A Study to Evaluate EMB 001 in Subjects With Cocaine Use Disorder

A Phase 2 interventional study of EMB-001 and EMB-001 Placebo in Cocaine Use Disorder, sponsored by Embera NeuroTherapeutics, Inc.. Completed at 4 sites in United States. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-09-21.

Sponsored by Embera NeuroTherapeutics, Inc. · Phase 2, Interventional, and Treatment

Phase
Phase 2
Study type
Interventional
Enrollment
82
Allocation
Randomized
Ages
18 Years to 65 Years
Sex
All
01

Study summary

EMB-001 is a combination of 2 drugs: the cortisol synthesis inhibitor, metyrapone (Metopirone®), and the benzodiazepine receptor agonist, oxazepam (original trade name Serax®; now marketed as oxazepam (generic) only).

This is a Phase 2 study in approximately 80 adult subjects with moderate-to-severe Cocaine Use Disorder (CUD).

Read the detailed description

This study is a Phase 2, randomized, double-blind, placebo-controlled, parallel-group, study to compare the safety and efficacy of EMB-001 with a placebo control in approximately 80 subjects with moderate-to-severe CUD. Subjects will receive investigational medicinal product (IMP) during a 12-week, double-blind Treatment Period (Week 2 through Week 13) and a 1-week, double-blind Taper Period (Week 14).

After undergoing study procedures during the Screening and Baseline Periods, subjects who meet inclusion and exclusion criteria will then be randomized in a 1:1 ratio (n=40/arm) to one of the following for the Treatment Period (weeks 2 - 13) on Study Day 8:

  • EMB-001 720 mg metyrapone/24 mg oxazepam mg BID, for a total daily dose of 1440 mg metyrapone and 48 mg oxazepam (Active Group)
  • Placebo BID, (Placebo Group)

During the Taper Period (week 14), subjects in the Active Group will receive EMB-001 240/8 mg BID; and the Placebo Group will continue to receive placebo. Both groups will change from taking three capsules BID (twice daily) to one capsule BID (twice daily).

There will be a follow-up visit for safety assessments at Week 18.

02

Conditions studied

  • Cocaine Use Disorder

Keywords

  • cocaine
03

Who can participate

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

Eligibility criteria

Key Inclusion Criteria:

  • Provide written informed consent prior to any study procedures
  • 18 to 65 years of age
  • DSM-5 diagnosis of moderate-to-severe CUD
  • Seeking treatment for CUD. Subjects with past rehabilitation attempts are eligible if the most recent rehabilitation attempt ended at least 30 days prior to Screening
  • Female subjects must be of non-childbearing potential
  • Male subjects must agree to use accepted contraceptive regimens during the study and for at least 90 days after the last dose of the study drug

Key Exclusion Criteria:

  • Any significant current medical conditions
  • Known hypersensitivity to or intolerance of oxazepam, metyrapone, or any benzodiazepine, or severe hypersensitivity reaction (e.g., angioedema) to any drug
  • Heightened likelihood of having adrenal insufficiency in the investigator's or designees' opinion
  • Current court-mandated treatment requirement for a substance-use disorder
  • Current DSM-5 moderate-to-severe substance use disorder, other than CUD, tobacco or caffeine
  • Current DSM-5 opioid or benzodiazepine use disorder of any severity
04

Study design

Phase
Phase 2
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
82 participants (actual)

Study arms

  • Active comparator
    EMB-001 Active

    EMB-001 Combination product of 720 mg metyrapone/24 mg oxazepam mg by mouth twice per day for 12 weeks followed by a 1 week taper

    Drug: EMB-001

  • Placebo comparator
    EMB-001 Placebo

    EMB-001 Placebo by mouth twice per day for 12 weeks followed by a 1 week taper

    Drug: EMB-001 Placebo

Interventions

  • DrugEMB-001

    720 mg metyrapone/24 mg oxazepam mg BID

  • DrugEMB-001 Placebo

    Inactive comparator

05

What researchers measure

Primary outcomes

  1. Continuous Abstinence From Cocaine Use

    The Primary Endpoint is the Percentage of Subjects That Successfully Achieve Abstinence From Cocaine During the Last Three Weeks of Treatment using the Timeline Follow Back; days of abstinence, confirmed by Urine benzoylecgonine (BE)

    Time frame: Week 11 to Week 13

Secondary outcomes

  1. Change in Cocaine-use Days (Weekly Average)

    Weekly cocaine use days 28 days prior to Screening (Time Line Follow-back (TLFB) only) to weekly use days during final 3 weeks of treatment (TLFB confirmed by urine BE)

    Time frame: Final 3 weeks of treatment (Weeks 11, 12 and 13 for subjects who complete the trial fully, but whichever weeks are the final 3 weeks for subjects who do not fully complete the trial) compared to the 28 days prior to screening.

  2. Reduction in Total Cocaine Craving Questionnaire-Brief Score

    The Cocaine Craving Questionnaire-Brief (CCQ-B) assesses current cocaine craving in routine clinical practice. The CCQ-B is a 10 item questionnaire and items are scored on a one to seven scale. Total responses are then divided by 10 to achieve a total craving score between 1.0 (least craving) to 7.0 (most craving).

    Time frame: Baseline to Week 13 (Day 91)

06

Results

Posted Sep 21, 2026

Participant flow

Participant flow — Overall Study
MilestoneEMB-001 ActiveEMB-001 Placebo
Started4141
Completed1819
Not completed2322

Outcome measures

PrimaryContinuous Abstinence From Cocaine Use

The Primary Endpoint is the Percentage of Subjects That Successfully Achieve Abstinence From Cocaine During the Last Three Weeks of Treatment using the Timeline Follow Back; days of abstinence, confirmed by Urine benzoylecgonine (BE)

Time frame:
Week 11 to Week 13
Reported as:
Count of participants · Participants
Continuous Abstinence From Cocaine Use
ParticipantsEMB-001 ActiveEMB-001 Placebo
Continuous Abstinence From Cocaine Use20
Statistical analysis
  • EMB-001 Active vs EMB-001 Placebo · Regression, Logistic · p = 0.092 · Odds ratio (or): 0 · 95% CI -0.0419 to 0.134983
SecondaryChange in Cocaine-use Days (Weekly Average)

Weekly cocaine use days 28 days prior to Screening (Time Line Follow-back (TLFB) only) to weekly use days during final 3 weeks of treatment (TLFB confirmed by urine BE)

Time frame:
Final 3 weeks of treatment (Weeks 11, 12 and 13 for subjects who complete the trial fully, but whichever weeks are the final 3 weeks for subjects who do not fully complete the trial) compared to the 28 days prior to screening.
Reported as:
Mean · Weekly cocaine use days
Change in Cocaine-use Days (Weekly Average)
Weekly cocaine use daysEMB-001 ActiveEMB-001 Placebo
Change in Cocaine-use Days (Weekly Average)0.6 ± 2.51.2 ± 1.6
SecondaryReduction in Total Cocaine Craving Questionnaire-Brief Score

The Cocaine Craving Questionnaire-Brief (CCQ-B) assesses current cocaine craving in routine clinical practice. The CCQ-B is a 10 item questionnaire and items are scored on a one to seven scale. Total responses are then divided by 10 to achieve a total craving score between 1.0 (least craving) to 7.0 (most craving).

Time frame:
Baseline to Week 13 (Day 91)
Reported as:
Mean · CCQ-B score
Reduction in Total Cocaine Craving Questionnaire-Brief Score
CCQ-B scoreEMB-001 ActiveEMB-001 Placebo
Reduction in Total Cocaine Craving Questionnaire-Brief Score-1.62 ± 2.0-2.63 ± 1.3

Adverse events

Collected over From randomization to follow-up visit (up to 18 weeks). Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
EMB-001 Active0/41 (0%)0/41 (0%)21/41 (51.2%)
EMB-001 Placebo0/41 (0%)0/41 (0%)25/41 (61%)
Most frequent other events
Most frequent other events
EventEMB-001 ActiveEMB-001 Placebo
SomnolenceNervous system disorders8/416/41
HeadacheNeoplasms benign, malignant and unspecified (incl cysts and polyps)4/416/41
DiarrheaGastrointestinal disorders3/415/41
ACTH stimulation test abnormalInvestigations4/410/41
FatigueGeneral disorders3/414/41
Increased appetiteMetabolism and nutrition disorders3/411/41
Decreased appetiteMetabolism and nutrition disorders2/413/41

Baseline characteristics

Age, Continuous
Age, Continuous(Years)EMB-001 ActiveEMB-001 PlaceboTotal
Mean50.6 ± 9.252.0 ± 7.551.3 ± 8.38
Sex: Female, Male
Sex: Female, Male(Participants)EMB-001 ActiveEMB-001 PlaceboTotal
Female437
Male373875
Race (NIH/OMB)
Race (NIH/OMB)(Participants)EMB-001 ActiveEMB-001 PlaceboTotal
American Indian or Alaska Native202
Asian000
Native Hawaiian or Other Pacific Islander000
Black or African American323163
White71017
More than one race000
Unknown or Not Reported000
Severity of cocaine use disorder (DSM-V)
Severity of cocaine use disorder (DSM-V)(Participants)EMB-001 ActiveEMB-001 PlaceboTotal
Moderate729
Severe343973
Number of days of cocaine use in the 28 days prior to Screening
Number of days of cocaine use in the 28 days prior to Screening(Days)EMB-001 ActiveEMB-001 PlaceboTotal
Mean20.1 ± 6.121.8 ± 6.520.9 ± 6.3
Cocaine use route of administration prior to Screening
Cocaine use route of administration prior to Screening(Participants)EMB-001 ActiveEMB-001 PlaceboTotal
Nasal141428
Nasal, Smoking9918
Oral101
Other: inhale101
Other: nasal and smoking112
Smoking151732
CCQ-B Score
CCQ-B Score(Score)EMB-001 ActiveEMB-001 PlaceboTotal
Mean3.7 ± 1.74.1 ± 1.33.9 ± 1.5
ACE Summary
ACE Summary(Scores on scale)EMB-001 ActiveEMB-001 PlaceboTotal
Mean1.8 ± 1.91.6 ± 2.01.7 ± 2.0
07

Study locations

4 sites
  • Pacific Treatment and Research Center, Department of Psychiatry, University of California, San Diego, School of Medicine
    San Diego, California 92092, United States
  • Segal Trials
    Miami, Florida 33161, United States
  • U PENN- Perelman School of Medicine
    Philadelphia, Pennsylvania 19104, United States
  • Medical University of South Carolina
    Charleston, South Carolina 29403, United States
08

References and documents

Publications

  • Kablinger AS, Lindner MA, Casso S, Hefti F, DeMuth G, Fox BS, McNair LA, McCarthy BG, Goeders NE. Effects of the combination of metyrapone and oxazepam on cocaine craving and cocaine taking: a double-blind, randomized, placebo-controlled pilot study. J Psychopharmacol. 2012 Jul;26(7):973-81. doi: 10.1177/0269881111430745. Epub 2012 Jan 11. PubMed 22236504 ↗

Study documents

  • Study protocol · Sep 22, 2020
  • Statistical analysis plan · Sep 22, 2020

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: Yes — Every three months, the NIDA DSMB will convene to review the overall safety data, as well as data on safety summarized by treatment condition. As per NIH guidelines, the objective of these reviews will be to determine whether continued conduct of the trial poses any undue risk for participants. Blinded data tables, figures and/or listings will be provided to the Data Safety Monitoring Board (DSMB).

Supporting information: Study protocol, Csr

09

Registry details

Key details

Study ID
NCT04501874
Lead sponsor
Embera NeuroTherapeutics, Inc.
Collaborators
National Institute on Drug Abuse (NIDA)
Responsible party
Sponsor
First posted
Aug 6, 2020
Start date
Jul 29, 2020
Primary completion
Jul 27, 2022
Completion
Oct 15, 2022
Results posted
Sep 21, 2026
Last update
Sep 21, 2026

Study contacts

Bruce McCarthy, MD
study chair · Embera NeuroTherapeutics, Inc.

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Start the discussion