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Recruiting Phase 3 NCT06412757

NCT06412757 Silexan in the Treatment Of Posttraumatic Stress Disorder Trial

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Clinical Trial Summary
NCT ID NCT06412757
Status Recruiting
Phase Phase 3
Sponsor Deakin University
Condition Post Traumatic Stress Disorder
Study Type INTERVENTIONAL
Enrollment 278 participants
Start Date 2024-08-26
Primary Completion 2027-05

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
SilexanPlacebo

Eligibility Fast-Check

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What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 3 trials are large pivotal studies comparing the treatment to current standard of care or placebo. Your participation directly contributes to the evidence needed for regulatory approval.

This trial targets 278 participants in total. It began in 2024-08-26 with a primary completion date of 2027-05.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

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 278 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.

Eligibility Criteria

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. Exclusion Criteria: 1. Are currently serving in the Australian Defence Force 2. Lifetime history of a psychotic or bipolar disorder, or dissociative identity 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, that would make participation in the trial unsafe or inappropriate. 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).

Contact & Investigator

Central Contact

Greg Roebuck, MD

✉ greg.roebuck@unimelb.edu.au

📞 +61 3 9035 4749

Principal Investigator

Michael Berk, PhD

PRINCIPAL INVESTIGATOR

Deakin University

Frequently Asked Questions

Who can join the NCT06412757 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, studying Post Traumatic Stress Disorder. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT06412757 trial and what does that mean for participants?

Phase 3 trials are large-scale studies comparing the new treatment to existing standards of care or a placebo. They provide the evidence needed for regulatory approval. This trial targets 278 participants.

Is NCT06412757 currently recruiting?

Yes, NCT06412757 is actively recruiting participants. Contact the research team at greg.roebuck@unimelb.edu.au for enrollment information.

Where is the NCT06412757 trial being conducted?

This trial is being conducted at Carlton, Australia, Geelong, Australia, Heidelberg, Australia, Melbourne, Australia.

Who is sponsoring the NCT06412757 clinical trial?

NCT06412757 is sponsored by Deakin University. The principal investigator is Michael Berk, PhD at Deakin University. The trial plans to enroll 278 participants.

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ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: July 2026  ·  Data Methodology