Acceptability of psilocybin-assisted group therapy in patients with cancer and major depressive disorder: Qualitative analysis

Depression is common among people with cancer and substantially worsens outcomes: up to one in five cancer patients meet criteria for major depressive disorder (MDD), and available treatments reach only a minority and produce full remission for only a small proportion. Previous randomised trials have demonstrated safety and promising efficacy of psilocybin-assisted therapy (PAT) for MDD in non-cancer populations, prompting regulatory interest, but the conventional individual-delivery model for PAT is resource intensive, requiring multiple sessions and two trained therapists per patient. These logistical demands constrain scalability and access for people with cancer who have psycho‑existential distress. To address scalability, group-based PAT approaches have been piloted in other populations (for example, long-term HIV survivors and healthy volunteers undergoing simultaneous dosing), but they had not been studied in people with cancer and comorbid MDD. Beaussant and colleagues therefore set out to explore the acceptability of a novel delivery model that combined simultaneous individual dosing with group preparation and integration sessions, drawing on participants from a Phase II open‑label trial in patients with cancer and MDD. The primary aim was to understand patients' cognitive and emotional responses to the group/simultaneous format and to identify factors that promote or impede acceptability of this model.

This qualitative study was conducted alongside a Phase II open‑label parent trial (NCT04593563) testing simultaneous administration of psilocybin in patients with cancer and MDD. The intervention regimen included five simultaneous individual sessions (visits 1–5) conducted in separate rooms with a 1:1 therapist/participant ratio and audio‑video supervision by two lead therapists in a separate space, plus group sessions at visits 2, 4, and 5. Cohorts comprised three to four participants; group sessions included the cohort participants, their individual therapists and the two lead therapists, amounting to five to six therapists per cohort depending on size. All 30 participants who completed the parent trial were eligible; convenience sampling yielded 28 participants who consented to the qualitative interviews. Interviews were conducted by Yvan Beaussant between January and November 2021 via Zoom, lasted on average 90 minutes (range 56–190 minutes), and took place a median of 2.9 months (range 2.1–5.1 months) after the psilocybin dosing day. Sessions were audio‑recorded, transcribed via a human transcription service and verified, and deidentified. The interview guide was developed by a multidisciplinary team and framed around Sekhon et al.'s conceptual framework of acceptability (affective attitude, burden, ethicality, intervention coherence, opportunity costs, perceived effectiveness, self‑efficacy). Analysis used template analysis combining deductive and inductive coding (April 2021–December 2022). The coding template incorporated the acceptability framework and the psychedelic concepts of set and setting; two coders independently coded an initial set of transcripts to refine the template, then transcripts were coded independently with biweekly meetings to reconcile differences and refine the codebook. Coding was performed in Dedoose (v9.0.54). The authors judged that the sample and richness of interviews provided sufficient information power to reach concept saturation. Participant characteristics were reported elsewhere in tabular form; the extracted text notes that 40% (n = 11) had prior psychedelic experience and that parent‑trial retention was 100%.

Twenty‑eight participants completed semi‑structured interviews. Overall, participants described the combined group and simultaneous individual PAT model as acceptable, reporting benefits in two broad domains: enhanced safety/preparedness and enriched therapeutic efficacy through connection and meaning. Before participation, some participants expressed fears about losing control, mental health deterioration or medical complications; these concerns were commonly allayed by the group context. For example, one participant said they were worried about losing their mind and dying, while others emphasised that the group made the dosing day "less scary… you're not alone." Many participants reported that hearing others' questions and stories during preparation helped them anticipate aspects of the experience they might not otherwise have anticipated. A recurring theme was a strengthened sense of connection and belonging. Several participants felt immediate comfort from shared illness and hopes for benefit; others initially felt awkward in the group but reported that such discomfort often dissipated after the dosing day. Group integration sessions were described as enriching and deepening meaning: hearing others' reports helped participants recall and reframe elements of their own experience, and some reported that shared disclosure aided integration and reduced post‑session anxiety. Participants also described experiences of compassion and self‑transcendence that extended beyond the individual session and sometimes carried over into relationships outside the study. The analysis identified several factors that influenced acceptability. The therapeutic framework was central: participants valued professional, accepting, non‑judgemental therapist presence and felt that this multilayered support contributed to safety and openness. Individual sessions were viewed as complementary to group activities; many participants valued the privacy of individual dosing rooms while appreciating group preparation and integration. Reported disruptive factors included distractions from simultaneous dosing (for example, hearing another participant cry next door), a sense of being observed or under an "excessive" number of therapists, comparisons with others' experiences leading to feelings of "missing out," and discomfort when cancer stages differed within the cohort. Some participants reported feeling like an impostor if they perceived their illness or distress to be less severe than others'. Participants offered divergent views on optimal group size and structure: some wanted more opportunities to interact with peers but fewer therapists present during group sessions. The extracted text does not provide the full demographic table or detailed counts for each theme beyond the note that 40% had prior psychedelic experience.

Beaussant and colleagues interpret their findings as indicating that an integrated model of simultaneous individual dosing with group preparation and integration is acceptable to patients with cancer and comorbid MDD when delivered within a supportive therapeutic framework. They argue that the group components increased participants' sense of safety and preparedness and fostered connection, meaning, and experiences of self‑transcendence and compassion, which the authors note are domains central to spirituality and may act as mediators of PAT's therapeutic effects. The therapeutic framework—shaping participants' mindset (set) and the environment (setting)—was emphasised as critical to creating a safe, non‑judgemental space that enabled existential work. The authors position these qualitative results in the context of scalability and implementation: delivering PAT in a community oncology setting (rather than a major academic centre) is notable because community hospitals provide most cancer care in the United States; a group/simultaneous model could reduce therapist time per patient and therefore improve access. They suggest exploring integration with existing psychotherapeutic and spiritual care models to maximise benefits. The investigators acknowledge the need for larger studies to confirm safety, efficacy, and cost‑effectiveness of the simultaneous model and to further investigate whether group approaches enhance mediators such as connectedness, meaning and transcendence. Regarding methodological rigour, the authors reference Lincoln and Guba's criteria (credibility, transferability, dependability, confirmability) and state that steps were taken to support trustworthiness, but the extracted text does not fully report the specific appraisals or outcomes of that framework. They also acknowledge limitations implied by the single‑centre, convenience‑sample design and the exploratory qualitative approach and call for further research to validate and operationalise the group PAT model for broader clinical use. Overall, the authors view the findings as encouraging for developing a more scalable approach to addressing psycho‑existential distress in patients with cancer.