American researchers reported the success of the second phase of clinical trials of combined individual and group psilocybin psychotherapy for the treatment of major depression in cancer patients. A report on the work was published in the journal Cancer; a separate publication in the same publication is devoted to the study of the subjective perception of such treatment.

Depression often accompanies cancer; clinically significant manifestations are observed in one out of three to four patients. At the same time, the traditional approach to treatment, including psychotherapy and the prescription of antidepressants, is often not effective enough. Because of this, psychedelic psychotherapy, including the use of psilocybin, is of great interest, which in clinical trials has repeatedly demonstrated high effectiveness in the treatment of major depressive disorder, post-traumatic stress disorder and other mental disorders.

The open-label (non-blinded) phase 2 clinical trial, conducted by Sunstone Therapies CEO Manish Agrawal and colleagues from several US research centers, included 30 cancer patients (average age 56 years). For two thirds of them, one to four years have passed since diagnosis; in 53.3 percent the disease was metastatic and inoperable. Among oncological diseases, breast cancer predominated (33.3 percent), as well as leukemia and lymphoma (26.7 percent). All participants suffered from major depressive disorder without moderate or severe psychotic features (HAM-D score 18 or more). They were not taking antidepressants, antipsychotics or medical cannabis at the time of recruitment.

After interview, assessment, and screening, each participant was assigned to an individual therapist and completed two orientation sessions that included information about psilocybin therapy. They then participated in weekly therapy sessions for eight weeks with 25 milligrams of synthetic psilocybin. In these sessions, the drug was administered to three to four patients at a time, who stayed in adjacent rooms of a community cancer center alone with their therapist for 4.25 hours, and then came together for 3.75 hours for group support and integration of the experience.

The dynamics of depression severity during therapy were assessed using the MADRS scale. At the eighth week, it decreased by an average of 19.1 points (p < 0.0001) compared to baseline. Sustained response to treatment was observed in 80 percent of participants; exactly half achieved complete remission of depressive symptoms in the first week, which persisted throughout the study. No serious side effects were recorded. Some patients complained of moderate and transient nausea and headache. Laboratory tests and ECG were without abnormalities. The participants did not show suicidal tendencies.

To determine the acceptability of combined individual and group psychotherapy using psilocybin for patients, the authors conducted semi-structured interviews with patients in a separate study; 28 people took part in them. In general, patients rated this approach positively in terms of both effectiveness and safety. Group sessions, on the one hand, increased their sense of security and preparedness, on the other hand, generated feelings of connectedness and community that helped to enrich and deepen everyone’s personal experience.