Long-term follow-up of psilocybin-assisted psychotherapy for psychiatric and existential distress in patients with life-threatening cancer
In a 3.2–4.5 year follow-up of cancer patients (n=15) from a prior crossover trial, single-dose psilocybin-assisted psychotherapy produced large, sustained reductions in anxiety, depression, hopelessness, demoralisation and death anxiety, with about 60–80% maintaining clinically significant antidepressant or anxiolytic responses. Participants overwhelmingly reported enduring positive, personally meaningful and spiritually significant life changes.
Authors
- Gabrielle Agin-Liebes
- Stephen Ross
- James Guss
Published
Abstract
Background
A recently published randomized controlled trial compared single-dose psilocybin with single-dose niacin in conjunction with psychotherapy in participants with cancer-related psychiatric distress. Results suggested that psilocybin-assisted psychotherapy facilitated improvements in psychiatric and existential distress, quality of life, and spiritual well-being up to seven weeks prior to the crossover. At the 6.5-month follow-up, after the crossover, 60–80% of participants continued to meet criteria for clinically significant antidepressant or anxiolytic responses.
Methods
The present study is a long-term within-subjects follow-up analysis of self-reported symptomatology involving a subset of participants that completed the parent trial. All 16 participants who were still alive were contacted, and 15 participants agreed to participate at an average of 3.2 and 4.5 years following psilocybin administration.
Results
Reductions in anxiety, depression, hopelessness, demoralization, and death anxiety were sustained at the first and second follow-ups. Within-group effect sizes were large. At the second (4.5 year) follow-up approximately 60–80% of participants met criteria for clinically significant antidepressant or anxiolytic responses. Participants overwhelmingly (71–100%) attributed positive life changes to the psilocybin-assisted therapy experience and rated it among the most personally meaningful and spiritually significant experiences of their lives.
Conclusion
These findings suggest that psilocybin-assisted psychotherapy holds promise in promoting long-term relief from cancer-related psychiatric distress. Limited conclusions, however, can be drawn regarding the efficacy of this therapy due to the crossover design of the parent study. Nonetheless, the present study adds to the emerging literature base suggesting that psilocybin-facilitated therapy may enhance the psychological, emotional, and spiritual well-being of patients with life-threatening cancer.
Research Summary of 'Long-term follow-up of psilocybin-assisted psychotherapy for psychiatric and existential distress in patients with life-threatening cancer'
Blossom's Take
Long-term follow-up data in psychedelic trials are limited. This study followed up with patients four years later and found that for most (about 70%) the positive effects persisted. Though the study is only in 15 people, and all had received a psychedelic dose (cross-over design) at the end of the study, it provides a positive signal for the enduring effects of psychedelic-assisted treatments.
Introduction
Cancer diagnoses commonly provoke substantial psychiatric and existential distress, with anxiety and depressive disorders reported in up to 40% of patients in hospital settings. Earlier research has found limited and inconsistent benefits from conventional psychotropic medications in this population, and psychosocial interventions targeting existential distress have shown only modest efficacy and methodological limitations. Historically, classical psychedelics were investigated for cancer-related distress in mid-20th century trials, and more recent randomized crossover trials of psilocybin and LSD with psychological support (total N≈104 across trials) have reported preliminary safety and medium-to-large acute therapeutic effects, but long-term outcome data remain sparse. Agin-Liebes and colleagues conducted a long-term follow-up (LTFU) of participants from a prior randomized, placebo-controlled crossover trial that compared a single dose of psilocybin (0.3 mg/kg) with a single dose of niacin (250 mg) combined with psychotherapy in patients with cancer-related psychiatric and existential distress (parent trial N=29). The present study aimed to determine whether the symptom reductions and improvements documented at parent study completion were maintained at two extended follow-up points conducted on average 3.2 years and 4.5 years after participants' psilocybin dosing date.
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Study Details
- Study Typeindividual
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- APA Citation
Agin-Liebes, G. I., Malone, T., Yalch, M. M., Mennenga, S. E., Ponté, K. L., Guss, J., Bossis, A. P., Grigsby, J., Fischer, S., & Ross, S. (2020). Long-term follow-up of psilocybin-assisted psychotherapy for psychiatric and existential distress in patients with life-threatening cancer. Journal of Psychopharmacology, 34(2), 155-166. https://doi.org/10.1177/0269881119897615
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