Psilocybin-assisted therapy shows range of benefits in cancer patients

Psychotherapy in combination with pharmacological treatments is often used to treat affective symptoms in patients with cancer. However, the effectiveness of the most commonly used medications is limited by the risk of adverse effects. Two ­placebo-controlled trials have found that patients with cancer-related psychiatric distress experienced rapid and sustained reductions in depressive and anxiety symptoms following one session of psilocybin-assisted psychotherapy. A new analysis of data from the two studies examined the effects of psilocybin-assisted therapy on a broader range of psychiatric symptoms. The trials employed a crossover design in which patients with cancer received high-dose psilocybin in one session and a control of niacin or low-dose psilocybin in the other. Investigators used the Brief Symptom Inventory to evaluate the effect of psilocybin-assisted therapy on nine psychiatric symptom dimensions: anxiety, depression, interpersonal sensitivity, hostility, obsession-compulsion, somatization, paranoia, phobia, and psychosis. Among the studies' 79 participants, psilocybin-assisted psychotherapy significantly improved anxiety, depression, interpersonal sensitivity, hostility, obsession-compulsion, and somatization. Psilocybin-assisted therapy also did not induce lasting paranoia, phobia, or psychosis, with the study's authors writing that these findings add “further evidence that psilocybin can be safely administered following rigorous screening under close medical supervision.” The researchers attributed the multidimensional effects of psilocybin in part to its action on the serotonin 2A receptor. “While larger clinical trials will ultimately be needed to validate these findings, our study suggests that [psilocybin-assisted psychotherapy] has the potential to be a comprehensive mental health treatment for patients with cancer,” the authors wrote. [P. Petridis et al. Nature Mental Health (2024), https://doi.org/10.1038/s44220-024-00331-0]