A Phase II, Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Efficacy and Safety of up to Two Doses of Psilocybin for the Treatment of Major Depressive Disorder in Adults With Cancer

Randomized, quadruple-blind, placebo-controlled Phase II study using group dosing sessions to evaluate fixed 25 mg oral psilocybin versus niacin 100 mg in adults with MDD and a malignant neoplasm.

Dosing Session 1 is randomized (psilocybin 25 mg or niacin 100 mg). Non-remitters (MADRS ≥10 at V7) may roll over into an open-label Session 2 to receive a second 25 mg psilocybin dose; participants are supported by a dedicated study therapist during group sessions.