Etomidate Use DisorderSToP-ENCT07736742
Repetitive Transcranial Magnetic Stimulation for People With Etomidate Addiction (SToP-E-rTMS x Etomidate)
A study testing high-frequency Repetitive Transcranial Magnetic Stimulation and Repetitive transcranial magnetic stimulation in people with Etomidate Use Disorder and Repetitive Transcranial Magnetic Stimulation (rTMS), run by The University of Hong Kong at 1 site in Hong Kong.
Trial summary
The goal of this clinical trial is to learn if high-frequency rTMS works to treat etomidate addiction in adults. It will also learn about the safety and tolerability of rTMS. The main questions it aims to answer are: Does active rTMS reduce craving, amount of etomidate use, frequency of etomidate use, and severity of… Read more about this study
- Who is it for?
- Ages 18 to 45 years
- Conditions the study is for
- Etomidate Use Disorder, Repetitive Transcranial Magnetic Stimulation (rTMS)
- What is being tested?
- high-frequency Repetitive Transcranial Magnetic Stimulation and Repetitive transcranial magnetic stimulation
- Type of treatment
- Medical device
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 40 participants
- Where
- 1 siteHong Kong
- Study dates
- 1 Sep 2026to 31 Mar 2029
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 45 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Able to read and communicate in English and/or Chinese
- Able to give informed consent and/or able to provide an informed consent from the legal guardian (if applicable)
- Using etomidate and/or its related analogues as the primary psychoactive substance of abuse
- Suffering from etomidate addiction as defined by:
- Etomidate Use Disorder classified under "Sedative-, Hypnotic-, or Anxiolytic Use Disorder" according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM-5-TR) with severity ≥ 1, or
- Harmful Use or Dependence for etomidate classified under "Mental and behavioral disorders due to use of sedatives or hypnotics" according to the International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10), or
- Hazardous use, harmful use or dependence classified under "Hazardous use of sedatives, hypnotics or anxiolytics" or "Disorders due to use of sedatives, hypnotics or anxiolytics" according to the Clinical descriptions and diagnostic requirements for International Classification of Diseases 11th Revision (ICD-11) mental, behavioral, and neurodevelopmental disorders.
Who cannot join
- Age < 18 years old
- Unable to read English or Chinese
- Unable to give informed consent
- Had been diagnosed with the following disorders including:
- 1. Neurodevelopmental Disorders:
- DSM-5: Intellectual Disabilities, Communication Disorders, Specific Learning Disorder, Autism Spectrum Disorder and Motor Disorders
Show all 15Show fewer
- International Statistical Classification of Diseases and Related Health Problems 11th Revision (ICD-11): Disorders of intellectual development (6A00), Developmental speech or language disorders (6A01), Autism spectrum disorder (6A02), Developmental learning disorder (6A03), Developmental motor coordination disorder (6A04), Stereotyped movement disorder (6A06), Primary tics or tic disorders (8A05.0)
- Other DSM-5 defined Substance Use Disorder greater than moderate in severity (i.e., severity score ≥4)
- Neurocognitive Disorders (DSM-5, or ICD-11 6D70-72 \& 6D80-86) 2. Contra-indicated to undergo rTMS:
- with electronic and/or magnetic implants (e.g., pacemaker, implantable cardioverter defibrillator [ICD], cerebral shunts, cochlear implant, etc.)
- with metallic or mechanic fragments (e.g., screws, plates, stents, clips, etc.)
- pregnant
- with any known or history of neurological conditions including cerebral vascular accidents (CVA), epilepsy, brain tumor or space occupying lesion, etc.
- poorly controlled or unstable diabetes mellitus
- receiving unstable dose(s) of antipsychotics, antidepressants, benzodiazepines and/or anticonvulsants in the past 3 months
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Hong Kong1 site
Queen Mary Hospital
Hong Kong, Hong Kong, 000000
Ablert KK Chung, chungkka@hku.hk
About this study
Official title: Substance Misuse To Psychiatric Disorders for Etomidate -Repetitive Transcranial Magnetic Stimulation for People With Etomidate Addiction: a 6-month, Double-blind, Randomized, Sham-controlled Trial
The goal of this clinical trial is to learn if high-frequency rTMS works to treat etomidate addiction in adults. It will also learn about the safety and tolerability of rTMS. The main questions it aims to answer are:
- Does active rTMS reduce craving, amount of etomidate use, frequency of etomidate use, and severity of etomidate use disorder?
- Does active rTMS improve cognitive biases related to delayed reward discounting and risk sensitivity?
- What side-effects do participants have when receiving rTMS?
Read more
Researchers will compare active rTMS to sham rTMS to see if active rTMS works to treat etomidate addiction.
Participants will:
- Receive active rTMS or sham rTMS over 4 weeks
- Complete 20 rTMS sessions in total
- Visit the clinic for treatment sessions and follow-up assessments
- Complete assessments of etomidate use, craving, withdrawal symptoms, mood symptoms, cognition, and decision-making
Attend follow-up assessments up to 6 months after baseline
Read the detailed description
This is a 6-month, double-blind, randomized, sham-controlled pilot clinical trial evaluating high-frequency repetitive transcranial magnetic stimulation (rTMS) for people with etomidate addiction. Etomidate misuse has become an emerging public health concern, but there is currently no established treatment specifically for etomidate addiction. This study will examine whether active rTMS delivered to the left dorsolateral prefrontal cortex can reduce etomidate craving, use, and dependence severity compared with sham rTMS.
The study will enroll 40 participants with etomidate use disorder. Participants will be randomly assigned in a 1:1 ratio to receive either active rTMS or sham rTMS. Both participants and outcome assessors will be blinded to treatment allocation. The intervention consists of 20 rTMS sessions delivered over 4 weeks, followed by an observation maintenance phase with follow-up assessments up to 6 months from baseline.
The study will assess changes in etomidate use, craving, withdrawal symptoms, dependence severity, anxiety, depression, global cognition, psychomotor speed, and cognitive biases related to delayed reward discounting and risk sensitivity. These assessments will help determine whether rTMS may be a feasible and potentially effective intervention for etomidate addiction and related decision-making processes.
- Being tested
- high-frequency Repetitive Transcranial Magnetic Stimulation, Repetitive transcranial magnetic stimulation
- Keywords
- Etomidate, rTMS, addiction
- Medical subject headings
- Behavior, Addictive
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
high-frequency Repetitive Transcranial Magnetic StimulationDevice
high-frequency rTMS using Magventure TMS system using the Coil Cool-B70 Active/Placebo Bended Butterfly coil is delivered at the dorsolateral prefrontal cortex of consented subjects
Repetitive transcranial magnetic stimulationDevice
Sham rTMS will be delivered using the Coil Cool-B70 Active/Placebo Bended Butterfly coil, which generates a negligible magnetic field. The sham procedure will follow the same schedule as the active rTMS arm.
| Study group | Role | What they receive |
|---|---|---|
| Active rTMS | Experimental | Subjects receive 20 high-frequency rTMS sessions over 4 weeks. Receives: Device: high-frequency Repetitive Transcranial Magnetic Stimulation |
| Sham rTMS | Sham comparator | Subjects receive 20 Sham rTMS sessions over 4 weeks. Receives: Device: Repetitive transcranial magnetic stimulation |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in etomidate craving
Change in craving measured by the Craving Automated Scale-Substance from baseline to follow-up. Higher scores indicate stronger craving.
Measured: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in etomidate withdrawal symptoms
Change in withdrawal symptoms measured by the Clinical Institute Withdrawal Assessment for Benzodiazepines from baseline to follow-up.
Measured: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in amount of etomidate use
Change in the amount of etomidate use over the past 30 days measured by the Beat Drugs Fund Evaluation Question Set No. 5 and substance use interview from baseline to follow-up.
Measured: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in frequency of etomidate use
Change in the frequency of etomidate use over the past 30 days measured by the Beat Drugs Fund Evaluation Question Set No. 5 and substance use interview from baseline to follow-up.
Measured: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in severity of dependence
Change in severity of dependence measured by the Severity of Dependence Scale from baseline to follow-up. Higher scores indicate greater dependence severity.
Measured: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in urine-confirmed etomidate use
Change in etomidate use status assessed by urine test from baseline to follow-up. Urine testing will be used to assess recent etomidate use and compare biological testing results with self-reported etomidate use.
Measured: Baseline, Week 1, Week 4, Month 3, and Month 6
Secondary outcomes (6)
Change in anxiety symptoms
Change in anxiety symptoms measured by the Beck Anxiety Inventory from baseline to follow-up. Higher scores indicate more severe anxiety symptoms.
Measured: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in depressive symptoms
Change in depressive symptoms measured by the Beck Depression Inventory-II from baseline to follow-up. Higher scores indicate more severe depressive symptoms.
Measured: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in delayed reward discounting
Change in delayed reward discounting measured by a delay discounting task from baseline to follow-up. The task assesses preference for smaller immediate rewards versus larger delayed rewards.
Measured: Baseline, Week 4, Month 3, and Month 6
Change in risk sensitivity
Change in risk sensitivity measured by a risk preference task from baseline to follow-up. The task assesses preference for smaller safe rewards versus larger risky rewards.
Measured: Baseline, Week 4, Month 3, and Month 6
Change in global cognitive function
Change in global cognitive function measured by the Montreal Cognitive Assessment-Hong Kong Chinese version or English version from baseline to follow-up. Higher scores indicate better global cognitive function.
Measured: Baseline, Week 4, Month 3, and Month 6
Change in psychomotor speed
Change in psychomotor speed measured by the Digit Symbol Substitution Test from baseline to follow-up. Higher scores indicate better psychomotor speed.
Measured: Baseline, Week 4, Month 3, and Month 6
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Jul 2026
- Study start1 Sep 2026 (estimated)
- Primary completion31 Aug 2028 (estimated)
- Study completion31 Mar 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Etomidate Use DisorderStudies of the same condition, open and under way.
- More trials run by The University of Hong KongThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- randomized, double-blinded, placebo (sham) controlled
- Masking
- Triple blind
- Who is masked
- Participant, Care provider, Outcomes assessor
- Enrolment
- 40 participants (estimated)
Sponsor and investigators
- Lead sponsor
- The University of Hong Kong
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Albert KK Chung, Principal investigator, Department of Psychiatry, The University of Hong Kong
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07736742
- Sponsor's protocol ID
- UW 26-263
- Acronym
- SToP-E
- Status last verified
- Jul 2026
- First submitted
- 26 Jul 2026
- Last updated
- 30 Jul 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: This is because of the potential legal consequences to the participants as etomidate abuse in the study locality is considered criminal.
Study at a glance
From the registry record, last updated by the sponsor on 30 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Substance Misuse To Psychiatric Disorders for Etomidate -Repetitive Transcranial Magnetic Stimulation for People With Etomidate Addiction: a 6-month, Double-blind, Randomized, Sham-controlled Trial
- ClinicalTrials.gov ID
- NCT07736742
- Acronym / sponsor ID
- SToP-E / UW 26-263
- Keywords
- Etomidate, rTMS, addiction
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 40 participants (estimated)
- Lead sponsor
- The University of Hong KongUniversity, hospital or other
- Study start
- 1 Sep 2026 (estimated)
- Primary completion
- 31 Aug 2028 (estimated)
- Study completion
- 31 Mar 2029 (estimated)
- First posted
- 30 Jul 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this clinical trial is to learn if high-frequency rTMS works to treat etomidate addiction in adults. It will also learn about the safety and tolerability of rTMS. The main questions it aims to answer are:
- Does active rTMS reduce craving, amount of etomidate use, frequency of etomidate use, and severity of etomidate use disorder?
- Does active rTMS improve cognitive biases related to delayed reward discounting and risk sensitivity?
- What side-effects do participants have when receiving rTMS?
Researchers will compare active rTMS to sham rTMS to see if active rTMS works to treat etomidate addiction.
Participants will:
- Receive active rTMS or sham rTMS over 4 weeks
- Complete 20 rTMS sessions in total
- Visit the clinic for treatment sessions and follow-up assessments
- Complete assessments of etomidate use, craving, withdrawal symptoms, mood symptoms, cognition, and decision-making
Attend follow-up assessments up to 6 months after baseline
Detailed description
This is a 6-month, double-blind, randomized, sham-controlled pilot clinical trial evaluating high-frequency repetitive transcranial magnetic stimulation (rTMS) for people with etomidate addiction. Etomidate misuse has become an emerging public health concern, but there is currently no established treatment specifically for etomidate addiction. This study will examine whether active rTMS delivered to the left dorsolateral prefrontal cortex can reduce etomidate craving, use, and dependence severity compared with sham rTMS.
The study will enroll 40 participants with etomidate use disorder. Participants will be randomly assigned in a 1:1 ratio to receive either active rTMS or sham rTMS. Both participants and outcome assessors will be blinded to treatment allocation. The intervention consists of 20 rTMS sessions delivered over 4 weeks, followed by an observation maintenance phase with follow-up assessments up to 6 months from baseline.
The study will assess changes in etomidate use, craving, withdrawal symptoms, dependence severity, anxiety, depression, global cognition, psychomotor speed, and cognitive biases related to delayed reward discounting and risk sensitivity. These assessments will help determine whether rTMS may be a feasible and potentially effective intervention for etomidate addiction and related decision-making processes.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, care provider, outcomes assessor)
- Number of arms
- 2
- Model description
- randomized, double-blinded, placebo (sham) controlled
| Arm | Type | Receives |
|---|---|---|
| Active rTMS | Experimental | Device: high-frequency Repetitive Transcranial Magnetic StimulationSubjects receive 20 high-frequency rTMS sessions over 4 weeks. |
| Sham rTMS | Sham comparator | Device: Repetitive transcranial magnetic stimulationSubjects receive 20 Sham rTMS sessions over 4 weeks. |
Who may qualify
- Ages
- 18 to 45 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (7 listed)
- Able to read and communicate in English and/or Chinese
- Able to give informed consent and/or able to provide an informed consent from the legal guardian (if applicable)
- Using etomidate and/or its related analogues as the primary psychoactive substance of abuse
- Suffering from etomidate addiction as defined by:
Key exclusion criteria (15 listed)
- Age < 18 years old
- Unable to read English or Chinese
- Unable to give informed consent
- Had been diagnosed with the following disorders including:
- DSM-5: Intellectual Disabilities, Communication Disorders, Specific Learning Disorder, Autism Spectrum Disorder and Motor Disorders
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| high-frequency Repetitive Transcranial Magnetic Stimulationhigh-frequency rTMS using Magventure TMS system using the Coil Cool-B70 Active/Placebo Bended Butterfly coil is delivered at the dorsolateral prefrontal cortex of consented subjects | Device | Active rTMS |
| Repetitive transcranial magnetic stimulationSham rTMS will be delivered using the Coil Cool-B70 Active/Placebo Bended Butterfly coil, which generates a negligible magnetic field. The sham procedure will follow the same schedule as the active rTMS arm. | Device | Sham rTMS |
Primary outcome
Change in etomidate craving
Time frame: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in craving measured by the Craving Automated Scale-Substance from baseline to follow-up. Higher scores indicate stronger craving.
Change in etomidate withdrawal symptoms
Time frame: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in withdrawal symptoms measured by the Clinical Institute Withdrawal Assessment for Benzodiazepines from baseline to follow-up.
Change in amount of etomidate use
Time frame: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in the amount of etomidate use over the past 30 days measured by the Beat Drugs Fund Evaluation Question Set No. 5 and substance use interview from baseline to follow-up.
Change in frequency of etomidate use
Time frame: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in the frequency of etomidate use over the past 30 days measured by the Beat Drugs Fund Evaluation Question Set No. 5 and substance use interview from baseline to follow-up.
Change in severity of dependence
Time frame: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in severity of dependence measured by the Severity of Dependence Scale from baseline to follow-up. Higher scores indicate greater dependence severity.
Change in urine-confirmed etomidate use
Time frame: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in etomidate use status assessed by urine test from baseline to follow-up. Urine testing will be used to assess recent etomidate use and compare biological testing results with self-reported etomidate use.
6 secondary outcomes
Change in anxiety symptoms
Time frame: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in depressive symptoms
Time frame: Baseline, Week 1, Week 4, Month 3, and Month 6
Change in delayed reward discounting
Time frame: Baseline, Week 4, Month 3, and Month 6
Change in risk sensitivity
Time frame: Baseline, Week 4, Month 3, and Month 6
Change in global cognitive function
Time frame: Baseline, Week 4, Month 3, and Month 6
Change in psychomotor speed
Time frame: Baseline, Week 4, Month 3, and Month 6
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 30 Jul 2026.
- Individual participant dataSharing planned: No. This is because of the potential legal consequences to the participants as etomidate abuse in the study locality is considered criminal.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Albert KK Chung principal investigator
Department of Psychiatry, The University of Hong Kong
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing high-frequency Repetitive Transcranial Magnetic Stimulation and Repetitive transcranial magnetic stimulation in people with Etomidate Use Disorder and Repetitive Transcranial Magnetic Stimulation (rTMS), run by The University of Hong Kong at 1 site in Hong Kong.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 15 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 30 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Hong Kong. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Albert KK Chung (+85260440993, Chungkka@hku.hk), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in etomidate craving (time frame: Baseline, Week 1, Week 4, Month 3, and Month 6). The study lists 6 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 30 Jul 2026.