Group format psychedelic-assisted therapy interventions: Observations and impressions from the HOPE trial

Lewis and colleagues situate the study in a long tradition of group use of classic psychedelics, from indigenous communal rituals to mid-20th century clinical research. The authors note that contemporary clinical trials of psilocybin-assisted therapy have largely used individual preparatory, dosing, and integration sessions with two therapists per participant, a model that poses substantial scalability challenges because of clinician time requirements. They highlight theoretical reasons why group formats might be therapeutically valuable for conditions associated with social isolation or existential distress, including the capacity of psychedelics to enhance interpersonal connectedness, prosociality, and empathy, and the known benefits of group cohesion for psychotherapy outcomes. This paper reports qualitative observations, patient-reported experience survey data, and therapist impressions from the HOPE pilot trial (HOPE: A Pilot Study of Psilocybin Enhanced Group Psychotherapy in Patients with Cancer), an institutional review board–approved open-label feasibility and safety study of a group-format psilocybin intervention for patients with a DSM-5 depressive disorder associated with a cancer diagnosis. The authors set out to describe participants' and therapists' experiences of the group model and to offer practical suggestions for protocol design, screening, setting, therapist roles, group process, music, timeline, and potential risks to inform future group-based psychedelic trials. The trial's primary clinical outcome data were still being collected and analysed at the time of reporting; the present paper focuses on qualitative and procedural lessons from the intervention.

The HOPE trial recruited patients from the Huntsman Cancer Institute via referrals from oncology, palliative care, and social work. Eligible participants met criteria for a DSM-5 depressive disorder with an underlying cancer diagnosis; the extracted text does not provide a full enumerated list of inclusion and exclusion criteria in the body (it refers to Appendix 1 for details). Screening involved chart review, contact with referring clinicians, telephone discussion of eligibility and logistics, and an in-person psychiatric and medical evaluation including the PHQ-9 and Columbia Suicide Severity Rating Scale. Participants provided informed consent and were assigned an individual therapist prior to the first preparatory session. The intervention comprised three 120-minute group preparatory sessions (each with ~90 minutes of group process and 30 minutes of individual breakout time), a single high-dose group psilocybin session (25 mg) held in an infusion suite, and three 120-minute group integration sessions spread over two weeks. Cohorts were small (4–6 participants per cohort, three cohorts in total). The group process drew on a supportive‑expressive model commonly used in cancer support groups, with elements of psychoeducation, intention setting, mindfulness and guided imagery, and discussion of existential themes. Therapist staffing came from a multidisciplinary ten-person team (social workers, psychologists, a nurse, and MDs) who had completed brief training programs in psychedelic-assisted therapy; two therapists had completed a certificate programme. The dosing session used a communal music playlist played over room speakers rather than individual headphones, and participant/therapist dyads were positioned in semi-private bays within the infusion suite; a private 'break-out' room was available but not used. For the qualitative evaluation, the investigators collected free-form written participant reports and administered the HOPE Patient-Reported Experience Questionnaire at 2 weeks after completion of the full intervention. Ten of 12 participants completed this survey. The five Likert-format questions reported in the extracted text probed perceived efficacy of the group dosing format, changes in connection with other group members, whether the dosing session felt like a natural extension of the preparatory work, the acceptability of a communal music track, and preference for an individual music track with headphones. Therapist impressions were gathered from a post-study group process session and email requests. The paper does not report a quantitative analytic plan for these qualitative data beyond descriptive reporting of survey completion and thematic synthesis of free-text responses.

Ten of 12 participants completed the qualitative survey administered two weeks after completing the intervention. The primary clinical outcome measures were still pending analysis; the reported results therefore focus on participant narratives and therapist impressions of the group-format protocol. Participants uniformly reported positive impressions of the group-based design in response to questions assessing whether the group format maximised individual therapeutic response, increased connection to other group members, and felt like a natural extension of preparatory work. Free-text responses emphasised rapid development of interpersonal closeness and a sense that individual stories and healing journeys became "woven" together. Several participants described reduced feelings of isolation and greater capacity to co-exist with illness; one participant attributed a diminished sense of limited time to both the psilocybin session and a meditation practice. Practical feedback included mixed responses about music and sensory aids: some participants welcomed the communal speaker-driven playlist while others wished for more personalised control (for example, "choosing my own music"), and two participants expressed discomfort with restricted eye coverings, noting preferences for either no eye shades or optional use. A minority described the physical setting as confining and suggested alternatives such as a couch or outdoor time, though logistical constraints were acknowledged. Therapist reports corroborated participants' impressions of rapidly intensified group cohesion. The team observed that shared anticipatory apprehension and subsequent relief created a potent communal bond, and that preparatory and integration sessions amplified themes raised during dosing. Therapists emphasised the importance of the individual breakout segments for establishing rapport and deeper autobiographical exploration. The lead therapist role was reported as valuable for providing structure, overseeing practical necessities, and offering a degree of objective distance. The private break-out room, while not ultimately used, was considered a reassuring contingency and was briefly discussed as an option when one participant found the playlist intolerable during dosing; the participant remained in the group space with supportive dyadic interventions and later appreciated the shared process.

Lewis and colleagues interpret the qualitative data as supportive of the feasibility and acceptability of a small-group model for psilocybin-assisted therapy among patients with cancer-related depressive disorders, while emphasising caveats and practical lessons. They note that even a clinically familiar or "medical" setting can be rendered acceptable if described to participants in advance and intentionally de‑medicalised with décor and rituals; providing opportunities to walk through the space pre-enrolment and a structured settling-in period on dosing day appeared helpful. The authors argue that small cohorts, deliberate screening, and the availability of a private break-out room can mitigate risks arising from heterogeneous subjective experiences, even if the break-out room may not be frequently employed. With regard to therapist staffing and roles, the team found value in maintaining one-on-one therapist–participant dyads across the intervention while adding a lead therapist to coordinate group process and oversee safety and logistics. The dyadic break-out segments were viewed as essential for rapport, safety, and individual narrative work. The authors recommend preserving substantial one-on-one contact if future protocols pursue further reductions in therapist:participant ratios, and they highlight the benefit of including the broader therapist team in group sessions to foster cohesion and shared experience. On group process and music, the supportive‑expressive framework combined with explicit education about psilocybin was judged effective in preparing participants and building bonds that could enhance the dosing session. The communal speaker playlist was used deliberately to emphasise the shared nature of the experience; while most participants found this acceptable, some expressed a desire for personalised music options. The investigators advise explicitly framing the communal playlist during preparation and planning playlist strategy for any break-out/private spaces. The authors raise important cautions about potential harms specific to group formats. Group contexts can amplify suggestibility, social comparison, and the possibility of marginalising participants who have divergent experiences. Given increased suggestibility on psychedelics, careful, consistent therapist conduct is essential to avoid inadvertent coercion; the paper references recent visibility of coercive and abusive behaviours in psychedelic therapy contexts and frames this as a reason for deliberate protocol development. Lewis and colleagues also identify an open empirical question about the optimal psychotherapeutic adjunct for psychedelic treatments—whether non‑directive supportive approaches or more structured, directive modalities (for example CBT or ACT) will ultimately prove most efficacious. They conclude by advocating for development of both nomothetic (generalisable) and idiographic (individualised) models for psychedelic-assisted group therapy, while emphasising rigorous screening, clear safety plans, and further empirical work to characterise best practices. The extracted text also reiterates a practical recommendation that prohibited medications should be washed out for at least five half-lives prior to study registration, but does not provide further pharmacological details.