Changes in trauma symptoms of discrimination after MDMA-assisted psychotherapy for posttraumatic stress disorder

Williams and colleagues frame the study around a gap in psychedelic and trauma research: although MDMA-assisted psychotherapy has been investigated for post-traumatic stress disorder, little is known about whether it also reduces trauma symptoms linked to discrimination, oppression, and marginalisation. The authors note that earlier psychedelic studies have included relatively few Black, Indigenous, and other people of colour, and that most trauma research has focused on discrete events rather than chronic social stressors such as racism, class-based oppression, and bias related to gender or sexual orientation. They also point out that the Trauma Symptoms of Discrimination Scale (TSDS) is a validated way to assess anxiety-related trauma symptoms caused by oppression-based trauma, but that no clinical trials had yet examined changes in such symptoms before and after psychedelic therapy. The purpose of this substudy was to add the TSDS to an expanded access programme of MDMA-assisted psychotherapy for treatment-resistant PTSD and examine whether symptoms of discriminatory trauma changed after treatment. The authors describe this as an exploratory, real-world assessment of feasibility and possible efficacy in a small subgroup of participants who experienced discrimination-related trauma. They present the work as an early step towards understanding whether culturally informed psychedelic-assisted psychotherapy may help people with marginalised identities.

This study was nested within MAPS’ expanded access programme for MDMA-assisted psychotherapy for patients with treatment-resistant PTSD who could not join a clinical trial. The parent programme provided up to 50 patients with access to treatment and was intended to generate real-world evidence on both therapeutic outcomes and the logistics of delivery. Participants were told about study risks and benefits and gave written informed consent. The treatment model consisted of three non-drug preparatory psychotherapy sessions, followed by three MDMA-assisted therapy sessions, with three non-drug integrative sessions after each MDMA session. The extracted text does not clearly report the MDMA dose or detailed session procedures in this substudy. The TSDS was added as an additional measure to assess discrimination-related trauma symptoms alongside standard safety and efficacy outcomes. Although 28 participants completed treatment and 24 completed the TSDS at post-treatment, only nine had TSDS data at both screening and post-treatment. Four of those nine reported no symptoms at either time point and were excluded, leaving a final analysable sample of five participants. The low paired completion rate was attributed to the late addition of the TSDS and inconsistent administration across participants. The main analysis was a paired-samples t-test comparing TSDS scores before and after treatment, with a reported correlation between pre- and post-treatment scores and an effect size estimate (Cohen’s d).

Five participants formed the final sample for the discrimination-trauma analysis. They completed the TSDS at screening and again after treatment. Baseline mean TSDS score was 63.20 (SD 16.44), falling to 39.40 (SD 10.74) after treatment. This represented a mean reduction of 24 points, or about 38%. The paired-samples t-test showed a statistically significant decrease in TSDS scores after MDMA-assisted psychotherapy, t(4) = 2.85, p = .046 (two-sided). The reported effect size was large, with Cohen’s d = 1.28 (95% CI 0.02 to 2.46). The correlation between baseline and post-treatment TSDS scores was weak, r = .10 (p = .87), suggesting little association between initial and final scores in this very small sample. The authors report that all five participants showed a decline in discrimination-related trauma symptoms. They also state that participants spanned multiple discrimination domains, including race/ethnicity, gender, class, age, and sexual orientation, and that some experienced more than one form of discrimination. The extracted text does not provide more detailed subgroup results, and it does not report adverse events in this substudy section.

Williams and colleagues interpret the findings as preliminary evidence that MDMA-assisted psychotherapy may reduce trauma symptoms associated with discrimination and oppression. They emphasise that the average TSDS reduction was substantial and that the improvement reached statistical significance despite the very small sample. In their view, the large effect size suggests that the treatment may meaningfully alleviate discrimination-related trauma symptoms across people with different marginalised identities. The authors position these results alongside earlier research suggesting that psychedelic interventions can reduce racial or discrimination-related stress symptoms. They argue that the study adds value because trauma research has often overlooked chronic social harms, and because psychedelic trials have historically under-represented BIPOC participants and other marginalised groups. They also highlight the apparent improvement seen in both racialised participants and White participants, which they present as suggestive of culturally inclusive efficacy when care is provided in a culturally sensitive setting. The main limitations they acknowledge are the extremely small sample size, limited statistical power, and exploratory nature of the analysis. They note that the TSDS was introduced late, creating a low rate of paired completion and possible selection bias. They also state that the open-label design without a control group means placebo effects and the effects of psychotherapy alone cannot be separated from MDMA effects. In addition, overlap between discrimination types made it difficult to isolate the influence of any single form of discrimination, and the sample may not generalise to all people with discrimination-related trauma, particularly those less willing to engage in MDMA-assisted therapy. The authors’ broader implication is that psychedelic-assisted psychotherapy should be culturally attuned and intersectional, with therapists actively recognising racism, marginalisation, historical mistrust, and identity-specific stressors. They suggest that future studies should use larger samples and more consistent measurement to examine moderators such as type and chronicity of discrimination, intersectional identity burden, therapist-participant cultural match, prior therapy, and expectancy effects. They also argue that culturally competent and affirming care is central to optimising outcomes, not merely an added feature.

The authors conclude that this small substudy provides encouraging preliminary evidence that MDMA-assisted psychotherapy may reduce symptoms of discriminatory trauma in marginalised populations. They state that the TSDS scores fell significantly after treatment and that both Asian and White participants showed large improvements, with no sign that any subgroup failed to benefit. However, they stress that these findings are only exploratory because of the very limited sample size, and that any apparent group differences or associations should be treated as speculative.