The FDA has greenlit a Phase 2 clinical trial to investigate the use of smoked cannabis in veterans suffering from post-traumatic stress disorder (PTSD). The study, involving 320 veterans with moderate-to-severe PTSD who have previously used cannabis, will evaluate the safety and efficacy of inhaled THC-dominant dried cannabis flower compared to placebo.
Trial Design and Objectives
The trial, known as MJP2, is funded by the Michigan Veteran Marijuana Research Grant Program and conducted by the Multidisciplinary Association for Psychedelic Studies (MAPS). It employs a parallel design to study the effects of inhaled high-THC potency cannabis versus placebo. Participants will self-titrate the dose, aligning with commercially available products in states permitting cannabis use. The primary endpoint focuses on the reduction in CAPS-5 total score, a clinician-administered scale assessing overall PTSD symptoms.
Overcoming Regulatory Hurdles
The FDA had initially placed a partial clinical hold on the trial in 2021. MAPS successfully addressed the agency's concerns, including those related to self-titration of high-THC cannabis and vaporization as a delivery method. While the FDA no longer objects to vaporization, it requires additional safety information on the device before the study commences.
Prior Research and Rationale
A previous pilot crossover study, MJP1, assessed various inhaled cannabis treatments (high THC, high cannabidiol, THC+cannabidiol) against placebo in 76 veterans with chronic PTSD. While all three cannabis treatments improved PTSD symptoms, anxiety, depression, and sleep quality, the effect of inhaled cannabis on PTSD symptoms was not statistically significantly different from placebo. High potency THC was observed to be the most effective in relieving PTSD symptoms in the previous study.
PTSD in Veterans: An Unmet Need
PTSD is a significant concern among military personnel, with over 23% experiencing the condition compared to approximately 6% of U.S. adults. Combat exposure and pre-existing mental health issues can contribute to PTSD in veterans. Current treatments are often inadequate, highlighting the urgent need for innovative therapies.
Mechanism of Action and Safety Considerations
Research suggests that THC may act on receptors in the brain involved in memory and fear, potentially reducing inflammation. Exclusion criteria for the MJP2 trial include patients with chronic obstructive pulmonary disease or asthma to mitigate the risk of respiratory adverse events. Common adverse events observed in the MJP1 study included throat irritation, anxiety, cough, headache, nausea, and paranoia.
