Treating nightmares in posttraumatic stress disorder with dronabinol: study protocol of a multicenter randomized controlled study (THC PTSD-trial)

BACKGROUND: Distressing nightmares are a core symptom of posttraumatic stress disorder (PTSD) and contribute to psychiatric comorbidity, impaired physical health and decreased social functioning. No specific pharmacological treatment for PTSD-related nightmares is yet approved. Preliminary clinical data indicate that cannabinoid agonists can improve nightmares and overall PTSD symptoms in patients with PTSD. The primary objective of the study is to examine the efficacy of oral dronabinol (BX-1) versus placebo in reducing nightmares in patients with PTSD. The secondary objectives of the study are to examine the efficacy of oral BX-1 in reducing other PTSD symptoms. METHODS: The study is designed as a multi-centric, double-blind, randomized (1:1), placebo-controlled, parallel group interventional trial. Eligible patients will be randomized to BX-1 or placebo, receiving a once-daily oral dose before bedtime for 10 weeks. Primary efficacy endpoint is the Clinician-Administered PTSD Scale (CAPS-IV) B2 score for the last week, measuring frequency and intensity of nightmares. Secondary efficacy endpoints are other disorder-specific symptoms in patients with PTSD. Further, tolerability and safety of dronabinol will be assessed. DISCUSSION: This randomized controlled trial will provide evidence whether treating patients with PTSD and nightmares with dronabinol is safe and efficacious. TRIAL REGISTRATION: NCT04448808, EudraCT 2019–002211-25. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12888-023-04818-5.