Post-traumatic stress disorder (PTSD) is among the most debilitating psychiatric conditions afflicting military veterans, which often persists unremittingly even after years of standard treatment with psychotherapy and pharmacotherapy. This new phase 2 clinical trial from Ohio State University investigated whether the treatment of such chronic PTSD cases with psilocybin-assisted psychotherapy would be associated with significant clinical improvements in participants. The study is necessary because the response to conventional treatment of PTSD often remains limited, and treatment dropout rates and suicide risk in veterans are unacceptably high.
The study discussed above explores the possibility of combining psychotherapy, as well as two sessions. In which the patients are given synthetic psilocybin, one of the psychoactive substances of magic mushrooms. To help them cope with the traumatic memories that are somehow persistent in them after the event. However, a more significant hypothesis that seems to be evident from the study is that the psychotherapy sessions combined with psychedelic medicines may fundamentally help the veteran in question to return to normal life.
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Psilocybin-assisted therapy in treating PTSD
PTSD is a type of psychiatric illness that arises after having an incident or incidences that can place a person’s life at risk. For example, after being attacked or a victim of an accident or being present in a bad incident of driving a car or any accidental fall on oneself can occur at the same instance. In fact, with veteran soldiers it has become more long-term and is becoming increasingly difficult to treat. It refers to prolonged symptoms and absence of response to standard medications like medication and psychotherapy.
What is psilocybin-assisted therapy? Psilocybin-assisted therapy is a relatively new practice in which the hallucinogenic chemical is introduced as a middle and brief time-limiting agent that facilitates deeper healing within a long-term psychotherapeutic and healing process. The treatment views psychotherapy as the building block of long-term confidence and competence, a framework for constructing a sound philosophy of life; the ingestion of the substance as a psychedelic trigger that opens up a self-discovery period in which the patient re-evaluates his or her traumatic life narrative; and the integrative phase in which the therapist helps the patient verbalize and implement the insights gained.
Rather than trying to suppress patients’ symptoms, PAT (Present-Absent Trauma Therapy) focuses on helping them to actively confront and recontextualize traumatic memories, decondition unproductive fear responses, and promote acceptance and forgiveness, a challenging process for patients who are used to feeling threatened and shut down. In this trial, the focus is on whether this catalytic process can be harnessed to help combat chronic PTSD in veterans who have been “locked in” by the condition following various unsuccessful interventions.
Read More: Psychedelic Therapy: A Paradigm Shift in Psychiatric Research
Experimental design
This open-label, phase 2 clinical trial was conducted at the Center for Psychedelic Drug Research and Education (CPDRE) in the Ohio State University College of Social Work, with clinical research at Ohio State’s Wexner Medical Center and College of Medicine. The study was preregistered at ClinicalTrials.gov (NCT05554094) and recruited treatment-resistant, US military veterans aged 21–64 years with severe, service-related post-traumatic stress disorder (PTSD) and treatment resistant to standard care for ≥6 months.
Initially, 3,600 applicants were screened, and 668 applicants were screened, with thirteen veterans providing informed consent and enrolling. One enrolled participant withdrew before dosing, and 12 individuals (nine adults, 3 females) completed the protocol. The baseline for all DSM-5 (CAPS-five) general assessments was a physician-administered PTSD scale of 35 or higher, indicating moderate to extreme symptom severity. Secondary goals were clinician- and self-rated changes in PTSD symptoms and an exploratory analysis of the magnitude of symptom reduction over the course of psychotherapy on your own versus after a psilocybin dose.
The treatment dose is in depth and fairly standardized: approximately 8 hours of preparatory psychotherapy, observed by means of synthetic psilocybin batches (15 mg and 25 mg), several weeks apart, and approximately 8 hours of put-up dosing integration therapy. Sessions are facilitated through skilled clinicians who adhere closely to manualized protocols, with clinical adherence rankings averaging 98% across observation visits. This setup allowed investigators, guided using first author Stacey Armstrong and senior author Alan Davis, to observe non-observation effects in coeffectiveness over a 11-week treatment window. Also look at how psilocybin interacts with the psychotherapeutic process.
Psychotherapeutic and pharmacological treatment for PTSD
Safety was a critical part of the study, given the vulnerable nature of the participants and the use of psychedelics on subjects with disorders associated with traumatic experience. In all 12 veterans who underwent the study, there were no major adverse reactions recorded; however, non-major adverse reactions included headaches, anxiety, and dizziness, while cardiovascular factors such as heart rate and blood pressure stayed within normal safety levels throughout the psilocybin sessions. It is notable that there was no increase in suicidality scores from baseline to one month after the second dosing session.
There was an average reduction of 27.5 points on CAPS-5 from baseline to one month with effect size. d=2.30,p<.001. At that same point, 75% of subjects (9 out of 12) reached clinical response and remission (no longer met clinical criteria for PTSD). Improvements occurred on the self-report measures as well, and participants, such as veteran Zachariah Collett (U.S. Army veteran), recounted moving from having constant inner conflict and anger to feeling at peace, still, accepting, and that their families responded positively.
Preliminary investigations found that symptom reduction was not attributable to the purely drug-placebo-hope-based factors of anticipation; however, changes from the preparatory phase of psychotherapy predicted subsequent outcomes, whereas anticipation did not. Implied: psychotherapy is actively at work before the drug in the form of early psychotherapeutic engagement and processes will the psilocin enhance and speed that effect. Observations from this and another study on this work, among traumatized people, suggest changes in emotional avoidance, self-compassion, forgiveness, and connection to another, also key recovery mechanisms in PTSD.
Author’s insights
Exploratory analyses showed that improvement was not dependent on a specific, drug-induced, drug-placebo-type expectation. Instead, improvements in symptom changes that occur during preparatory psychotherapy can predict the drug outcome; in contrast, there’s not so with expectancy. Therefore, psychotherapy and a general of therapeutic interactions already facilitate improvements that may, or may not, be sped and deepened by this subsequent treatment in a population of trauma participants where positive changes have already been seen in the dimensions of decreased emotion avoidance, self-compassion, and ability to forgive others and bond to others that are all very relevant for treating the symptoms that occur with these conditions.
Also addressed is the “magic is not the drug itself” issue, a conceptual point the authors of the latest report, Alan Davis and several collaborators, make throughout: The combination of psilocybin and psychotherapy, in their view, enables the drug to act as a biological facilitator by “breaching an emotional bottleneck so patients can address traumatic material without the same level of defended coping and to have an easier time making narrative progress”, most of which happens within and after the individual therapy, not directly during the 8 hours of sitting with the drug experience itself.
Future direction includes tracking participants up to six months down the line, including biomarkers of sleep and substance use, as well as efforts to fund large-scale randomized, controlled trials, which help quantify just how much is attributable to each factor in drug and therapy contributions to outcome.
More broadly, the results complement a growing body of evidence that therapeutic use of psychedelics has the potential to ease the distress of trauma, make patients feel more able to engage with trauma memories, and increase feelings of self-forgiveness and acceptance, though the full process, or what risks might be involved long-term, are not yet well understood. The research could be part of what the authors are calling an “extremely exciting” period in the treatment of mental illness, with the eventual possibility of carefully managed psychedelic therapies being a helpful supplement to current options for PTSD.
Conclusion
In summary, this open-label, phase 2 study indicates that psilocybin-assisted therapy can be safely administered to treatment-resistant and treatment-refractory cases of severe PTSD among U.S. military veterans with an absence of any severe adverse events and a lack of enhancement of suicidal ideation or suicidal behavior among participants. In an 11-week treatment protocol involving in-depth preparatory and integration psychotherapy surrounding a total of 2 dosing sessions, the study participants demonstrated significant decreases in PTSD symptom severity, and 3/4 of the treatment participants were no longer meeting DSM criteria for PTSD one month post-treatment.
Beyond the numbers, it provides a snapshot into how the marriage of psychedelic pharmacology and evidence-based talk therapy could lead veterans away from the anxiety, rage, and confusion that grips them on the inside and toward increased acceptance, emotional malleability, and connectedness. While further rigorous investigation with controlled studies and follow-ups will be required before broad statements can be made, this pilot work offers an early indication that psilocybin-assisted therapy could be a potent treatment option going forward for those who have found little relief elsewhere, presenting something more than symptom reduction but a new lens through which to face their trauma.
References +
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