Study protocol of an open-label proof-of-concept trial examining the safety and clinical efficacy of psilocybin-assisted therapy for veterans with PTSD.

Introduction: Psilocybin-assisted therapy has shown significant promise in treating the cluster of mood and anxiety symptoms that comprise post-traumatic stress disorder (PTSD) but has yet to be tested specifically in this condition. Furthermore, current pharmacological and psychotherapeutic treatments for PTSD are difficult to tolerate and limited in efficacy, especially in the US Military Veteran (USMV) population. This open-label pilot study will examine the safety and efficacy of two psilocybin administration sessions (15 mg and 25 mg), combined with psychotherapy, among USMVs with severe, treatment resistant PTSD.