Psilocybin-assisted treatment for depression safe, effective through 12 months

Through 12 months, psilocybin-assisted treatment showed to be safe and effective for major depressive disorder, researchers reported in the Journal of Psychopharmacology.

Natalie Gukasyan, MD, assistant professor of psychiatry and behavioral sciences at Johns Hopkins University in Baltimore, and colleagues conducted a randomized, waiting-list controlled study of 24 patients between the ages of 21 and 75 years, with moderate to severe unipolar depression.

Participants were randomized to either an immediate treatment, or a delayed treatment by 8 weeks, in which they received two doses of psilocybin with supportive therapy. The 24 participants completed both psilocybin sessions and were followed for 12 months after the second dose.

Participants were evaluated at baseline, 1 week post-treatment, and 1, 3, 6 and 12 months following their second dose. Depression levels were assessed through GRID-HAMD scores. Of the 24 participants, 13 received immediate treatment, and 11 delayed.

From a baseline score of 22.8 for depressive symptoms, scores decreased to 8.7 after 1 week, 8.9 after 1 month, 9.3 after 3 months, 7.0 after 6 months, and 7.7 after 12 months. Effect sizes for these differences were large, the authors reported: 1 month, Cohen d = 2.3 (95% CI, 1.5-3.1); 3 months, 2.0 (95% CI, 1.3-2.7); 6 months, 2.6 (95% CI, 1.7-3.4); and 12 months, 2.4 (95% CI, 1.6-3.2).

No serious adverse events were reported among the participants.

“The present study suggests that two doses of psilocybin provided in the context of supportive therapy for MDD produced large and stable antidepressant effects throughout a 12-month follow-up period,” Gukasyan and colleagues wrote.