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Trial details imported from ClinicalTrials.gov

For full trial details, please see the original record at https://clinicaltrials.gov/study/NCT06412757




Registration number
NCT06412757
Ethics application status
Date submitted
9/05/2024
Date registered
14/05/2024
Date last updated
28/08/2024

Titles & IDs
Public title
Silexan in the Treatment Of Posttraumatic Stress Disorder Trial
Scientific title
Silexan in the Treatment Of Posttraumatic Stress Disorder (STOP) Trial
Secondary ID [1] 0 0
HT9425-23-1-0885
Secondary ID [2] 0 0
29307
Universal Trial Number (UTN)
Trial acronym
STOP
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Post Traumatic Stress Disorder 0 0
Condition category
Condition code
Mental Health 0 0 0 0
Anxiety
Mental Health 0 0 0 0
Other mental health disorders
Mental Health 0 0 0 0
Depression

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Treatment: Drugs - Silexan
Other interventions - Placebo

Experimental: Silexan 160 mg - Participants in the Silexan arm will take Silexan 160 mg daily in the morning for 12 weeks in addition to their usual prescribed psychoactive medications. Participants will be followed up at 2, 4, 6, 8 and 12 weeks of the intervention period, as well as at 4 weeks post-treatment (off-treatment follow-up period).

Placebo comparator: Placebo - Participants in this arm will take two placebo capsules daily in the morning for 12 weeks in addition to their usual medications. Participants will be followed up at 2, 4, 6, 8 and 12 weeks of the intervention period, as well as at 4 weeks post-treatment (off-treatment follow-up period).


Treatment: Drugs: Silexan
Participants in the Silexan arm will take two over-encapsulated capsules, each containing 80 mg Silexan, daily orally in the morning in addition to their usual medications. No modifications of allocated interventions will be made for any trial participants; if appropriate (i.e following the emergence of adverse events) participants will be withdrawn from the intervention.

Other interventions: Placebo
Participants in the placebo arm will take two capsules containing an inert placebo daily orally in the morning in addition to their usual medications. The placebo capsules will contain a sub-therapeutic amount of lavender oil to mimic the odor of the experimental drug (Silexan).
Intervention code [1] 0 0
Treatment: Drugs
Intervention code [2] 0 0
Other interventions
Comparator / control treatment
Control group

Outcomes
Primary outcome [1] 0 0
Clinician-Administered PTSD Scale for DSM-5 (CAPS-5)
Timepoint [1] 0 0
At baseline and at week 12 of the study period
Secondary outcome [1] 0 0
Clinician-Administered PTSD Scale for DSM-5 (CAPS-5)
Timepoint [1] 0 0
At baseline, at week 12 and at week 16 of the study period
Secondary outcome [2] 0 0
Hamilton Anxiety Rating Scale (HAM-A)
Timepoint [2] 0 0
At baseline, at week 12 and at week 16 of the study period
Secondary outcome [3] 0 0
Generalized Anxiety Disorder-7 (GAD-7)
Timepoint [3] 0 0
At baseline, at week 12 and at week 16 of the study period
Secondary outcome [4] 0 0
Generalized Anxiety Disorder-7 (GAD-7)
Timepoint [4] 0 0
At baseline, week 4, week 8 and week 12 of the study period
Secondary outcome [5] 0 0
Beck Depression Inventory-II (BDI-II)
Timepoint [5] 0 0
At baseline, at week 12 and at week 16 of the study period
Secondary outcome [6] 0 0
Patient Health Questionnaire-9 (PHQ-9)
Timepoint [6] 0 0
At baseline, at week 12 and at week 16 of the study period
Secondary outcome [7] 0 0
Patient Health Questionnaire-9 (PHQ-9)
Timepoint [7] 0 0
At baseline, week 4, week 8 and week 12 of the study period
Secondary outcome [8] 0 0
Patient Health Questionnaire-15 (PHQ-15)
Timepoint [8] 0 0
At baseline, at week 12 and at week 16 of the study period
Secondary outcome [9] 0 0
Patient Health Questionnaire-15 (PHQ-15)
Timepoint [9] 0 0
At baseline, week 4, week 8 and week 12 of the study period
Secondary outcome [10] 0 0
Pittsburgh Sleep Quality Index, with Addendum for PTSD (PSQI & PSQI-A)
Timepoint [10] 0 0
At baseline, at week 12 and at week 16 of the study period
Secondary outcome [11] 0 0
Pittsburgh Sleep Quality Index, with Addendum for PTSD (PSQI & PSQI-A)
Timepoint [11] 0 0
At baseline, week 4, week 8 and week 12 of the study period
Secondary outcome [12] 0 0
Alcohol Use Disorders Identification Test (AUDIT)
Timepoint [12] 0 0
At baseline, at week 12 and at week 16 of the study period
Secondary outcome [13] 0 0
Alcohol Use Disorders Identification Test (AUDIT)
Timepoint [13] 0 0
At baseline, week 4, week 8 and week 12 of the study period
Secondary outcome [14] 0 0
World Health Organization (WHO) Disability Assessment Schedule (WHODAS 2.0)
Timepoint [14] 0 0
At baseline, at week 12 and at week 16 of the study period
Secondary outcome [15] 0 0
General Well Being Schedule (GWBS)
Timepoint [15] 0 0
At baseline, at week 12 and at week 16 of the study period
Secondary outcome [16] 0 0
Assessment of Quality of Life-6D (AQoL-6D)
Timepoint [16] 0 0
At baseline, at week 12 and at week 16 of the study period
Secondary outcome [17] 0 0
PTSD Checklist for DSM-5 (PCL-5)
Timepoint [17] 0 0
At intake, at week 12 and at week 16 of the study period
Secondary outcome [18] 0 0
PTSD Checklist for DSM-5 (PCL-5)
Timepoint [18] 0 0
At intake, week 2, week 4, week 6, week 8 and week 12 of the study period
Secondary outcome [19] 0 0
Patient Global Impression of Change Scale (PGIC)
Timepoint [19] 0 0
Week 2, week 4, week 6, week 8 and week 12 of the study period
Secondary outcome [20] 0 0
Actigraphy watches
Timepoint [20] 0 0
Continously from baseline until week 16 of the study period

Eligibility
Key inclusion criteria
1. Aged 18 years or over.
2. Fluent in English.
3. Meet DSM-5 criteria for PTSD, irrespective of occupation (e.g. first responder, police officer, ex-military or civilian), determined using the Mini International Neuropsychiatric Interview 7.0.2.
4. Have a score on the PTSD Checklist for DSM-5 (PCL-5) equal to or over 33.
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
1. Are currently serving in the Australian Defence Force
2. Lifetime history of a psychotic or bipolar disorder.
3. Moderate or severe alcohol or other substance use disorder within 3 months of screening.
4. Active suicidal or homicidal ideation.
5. Borderline Personality Disorder (BPD).
6. Acute or unstable medical illness or other significant medical condition, including cardiovascular disease, epilepsy and chronic liver or kidney disease.
7. Pregnancy, lactation or unwillingness to use an acceptable method of contraception (required for both males and females who are of reproductive potential and sexually active with partners of the opposite sex) through the duration of participants' involvement in the study up to and including week 16. Participants will also be advised not to donate eggs or sperm during the study period.
8. Commencement of a trauma-focussed psychotherapy (including Prolonged Exposure, Cognitive Processing Therapy and Eye Movement Desensitisation and Reprocessing) within 3 months of screening.
9. Commencement or change in dose of psychoactive medications within 4 weeks of screening.
10. Participants will be asked not to initiate psychotherapy or change the dose of psychoactive medications during the course of the study except in clinically urgent circumstances; if this becomes necessary, a decision will be made on a case-by-case basis with regard to retaining the participant or terminating their participation.
11. Severe acquired brain injury.
12. Individual is not eligible for public mental health services due to their visa status in Australia or for any other reason.
13. Any other condition that in the opinion of the research team is likely to make completion of the trial requirements infeasible.
14. Inability to understand or speak English to the extent necessary to give informed consent and complete the trial (researcher or clinician-determined).

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Phase 3
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Anticipated
Actual
26/08/2024
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
31/03/2027
Actual
Sample size
Target
224
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
VIC
Recruitment hospital [1] 0 0
University of Melbourne - Carlton
Recruitment hospital [2] 0 0
Deakin University - Geelong
Recruitment hospital [3] 0 0
Austin Health - Heidelberg
Recruitment hospital [4] 0 0
Ramsay Clinic Albert Road - Melbourne
Recruitment postcode(s) [1] 0 0
5053 - Carlton
Recruitment postcode(s) [2] 0 0
3220 - Geelong
Recruitment postcode(s) [3] 0 0
3084 - Heidelberg
Recruitment postcode(s) [4] 0 0
3004 - Melbourne

Funding & Sponsors
Primary sponsor type
Other
Name
Deakin University
Address
Country
Other collaborator category [1] 0 0
Other
Name [1] 0 0
University of Melbourne
Address [1] 0 0
Country [1] 0 0
Other collaborator category [2] 0 0
Other
Name [2] 0 0
Ramsay Clinic Albert Road
Address [2] 0 0
Country [2] 0 0

Ethics approval
Ethics application status

Summary
Brief summary
Posttraumatic stress disorder (PTSD) is a common and debilitating mental illness. Current treatments for PTSD include psychotherapy and antidepressant medications. Many patients are unable to tolerate psychotherapy for PTSD and drop out of it. In addition, its effectiveness is limited. Up to 50 percent of patients who receive psychotherapy do not benefit from it. Antidepressant medications have only small benefits in PTSD. They also have unpleasant side effects that can make patients unwilling to take them. There is an urgent need to develop new treatments for PTSD that work and are well-tolerated. Silexan has the potential to provide an important alternative treatment for PTSD.

Silexan is derived from lavender oil. It is taken orally in the form of capsules. It is currently available over-the-counter in 14 countries, including Australia and the United States. Previous research has shown that it is an effective treatment for anxiety disorders, including Generalized Anxiety Disorder. It is also well-tolerated by patients. The only side effects that have been identified so far are mild gastrointestinal symptoms (including burping and breath odour) and these are uncommon. The results of a small pilot study suggest that Silexan may also be effective and well-tolerated in PTSD.

The STOP trial is a clinical trial that aims to investigate whether adding Silexan to treatment-as-usual improves PTSD symptoms in adults with PTSD. The trial will recruit 224 participants. Participants will be randomly assigned to take Silexan or a placebo (look-alike dummy pills) daily in addition to their usual medications for 12 weeks. The severity of their PTSD symptoms will be assessed prior to and at the end of this 12-week period.

The STOP trial has the potential to obtain definitive evidence regarding whether Silexan helps treat symptoms of PTSD. If Silexan is found to be an effective treatment for PTSD, the pool of patients who could potentially benefit from this treatment includes any adults with PTSD. Silexan is already available over-the-counter at a relatively low cost so there will be few barriers to accessing this treatment.
Trial website
https://clinicaltrials.gov/study/NCT06412757
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 0 0
Michael Berk, PhD
Address 0 0
Deakin University
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Greg Roebuck, MD
Address 0 0
Country 0 0
Phone 0 0
+61 3 9035 4749
Fax 0 0
Email 0 0
[email protected]
Contact person for scientific queries



Summary Results

For IPD and results data, please see https://clinicaltrials.gov/study/NCT06412757