RecruitingPhase 3NCT06412757

Silexan in the Treatment Of Posttraumatic Stress Disorder Trial

Silexan in the Treatment Of Posttraumatic Stress Disorder (STOP) Trial

Sponsor

Deakin University

Enrollment

278 participants

Start Date

Aug 26, 2024

Study Type

INTERVENTIONAL

Conditions

Post Traumatic Stress Disorder

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

Min Age: 18 Years

Inclusion Criteria4

Aged 18 years or over.
Fluent in English.
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.
Have a score on the PTSD Checklist for DSM-5 (PCL-5) equal to or over 33.

Exclusion Criteria14

Are currently serving in the Australian Defence Force
Lifetime history of a psychotic or bipolar disorder, or dissociative identity disorder.
Moderate or severe alcohol or other substance use disorder within 3 months of screening.
Active suicidal or homicidal ideation.
Borderline Personality Disorder (BPD).
Acute or unstable medical illness or other significant medical condition, that would make participation in the trial unsafe or inappropriate.
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.
Commencement of a trauma-focussed psychotherapy (including Prolonged Exposure, Cognitive Processing Therapy and Eye Movement Desensitisation and Reprocessing) within 3 months of screening.
Commencement or change in dose of psychoactive medications within 4 weeks of screening.
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.
Severe acquired brain injury.
Individual is not eligible for public mental health services due to their visa status in Australia or for any other reason.
Any other condition that in the opinion of the research team is likely to make completion of the trial requirements infeasible.
Inability to understand or speak English to the extent necessary to give informed consent and complete the trial (researcher or clinician-determined).

Interventions

DRUGSilexan

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.

OTHERPlacebo

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).