Single-Dose Psilocybin for a Treatment-Resistant Episode of Major Depression.

BACKGROUND: Psilocybin is being studied for use in treatment-resistant depression. METHODS: In this phase 2 double-blind trial, we randomly assigned adults with treatment-resistant depression to receive a single dose of a proprietary, synthetic formulation of psilocybin at a dose of 25 mg, 10 mg, or 1 mg (control), along with psychological support. The primary end point was the change from baseline to week 3 in the total score on the Montgomery-Åsberg Depression Rating Scale (MADRS; range, 0 to 60, with higher scores indicating more severe depression). Secondary end points included response at week 3 (≥50% decrease from baseline in the MADRS total score), remission at week 3 (MADRS total score ≤10), and sustained response at 12 weeks (meeting response criteria at week 3 and all subsequent visits). RESULTS: A total of 79 participants were in the 25-mg group, 75 in the 10-mg group, and 79 in the 1-mg group. The mean MADRS total score at baseline was 32 or 33 in each group. Least-squares mean changes from baseline to week 3 in the score were -12.0 for 25 mg, -7.9 for 10 mg, and -5.4 for 1 mg; the difference between the 25-mg group and 1-mg group was -6.6 (95% confidence interval [CI], -10.2 to -2.9; P<0.001) and between the 10-mg group and 1-mg group was -2.5 (95% CI, -6.2 to 1.2; P = 0.18). In the 25-mg group, the incidences of response and remission at 3 weeks, but not sustained response at 12 weeks, were generally supportive of the primary results. Adverse events occurred in 179 of 233 participants (77%) and included headache, nausea, and dizziness. Suicidal ideation or behavior or self-injury occurred in all dose groups. CONCLUSIONS: In this phase 2 trial involving participants with treatment-resistant depression, psilocybin at a single dose of 25 mg, but not 10 mg, reduced depression scores significantly more than a 1-mg dose over a period of 3 weeks but was associated with adverse effects. Larger and longer trials, including comparison with existing treatments, are required to determine the efficacy and safety of psilocybin for this disorder. (Funded by COMPASS Pathfinder; EudraCT number, 2017-003288-36; ClinicalTrials.gov number, NCT03775200.).

[Treatment with psilocybin: applications for patients with psychiatric disorders]. / Behandeling met psilocybine.

After a cessation of almost 40 years, there is renewed interest into therapeutic applicationsof the serotonergic psychedelic psilocybin for the treatment of patients with various psychiatric disorders. PubMed was searched for clinical trials into "psilocybin" between 2000 and 2020, complemented by handsearching. Articles were also screened for explanatory models and working mechanisms. Psilocybin has been studied in 9 clinical trials: for the treatment of substance use disorders, depression, end-of-life anxiety, demoralization, and obsessive-compulsive disorder. Results show that psilocybin is well tolerated, with only limited side-effects, while even patients with treatment-resistant disorders sometimes show marked, long-term improvements after one or a few sessions. Initial results are encouraging, but there are several limitations. More research is needed to determine which patient populations can benefit, what role setting and the placebo response play, and how these novel treatments can be optimized.