Psilocybin shows therapeutic potential for depression

For cancer patients with depression, treatment with a single dose of psilocybin appears to yield rapid and meaningful improvements in depressive symptoms, as shown in a phase II study.

The study included 30 participants (mean age 56 years, 70 percent women) who received a 25-mg dose of COMP360 psilocybin therapy, supplemented by individual therapy. Of these, 14 (47 percent) participants had curable cancers while 16 (53 percent) had noncurable cancers. Fifteen participants reported previous exposure to antidepressant drugs.

Outcome measures included safety and improvement in depression, which was assessed using the Montgomery-Asberg Depression Rating Scale (MADRS), with higher scores indicating greater severity. A decrease in MADRS score of at least 50 percent from baseline to week 3 and week 8 indicated sustained response to treatment. On the other hand, remission was defined as a MADRS score of <10 post-treatment. Other measures of depression included the Quick Inventory of Depressive Symptomatology–Self-Report and the Maudsley Visual Analogue Scale.

None of the patients had treatment-related serious adverse events (AEs). Furthermore, there was no evidence of suicidality, as measured on the Columbia Suicide Severity Rating Scale. AEs were mild or expected and included headache (n=24), nausea (n=12), altered mood (n=8), anxiety (n=7), and hallucinations (n=1).

By week 8, MADRS scores had decreased significantly by 19.1 points (95 percent confidence interval [CI], −22.3 to −16.0; p<0.001). Sustained response was seen in 24 participants (80 percent), with 15 (50 percent) achieving full remission of depressive symptoms.

The improvements were supported by self-reported measures of depressive symptoms. Quick Inventory of Depressive Symptomatology–Self-Report scores decreased by an average of 5.9 points (95 percent CI, −7.2 to −4.6), which translated to a 48-percent reduction from baseline to week 8. Additionally, the Maudsley Visual Analogue Scale decreased by −46.2 points (95 percent CI, −61.6 to −30.7), translating to a 53-percent reduction in self-rated depression severity.