Single-Dose Psilocybin for Depression With Severe Treatment Resistance: An Open-Label Trial.

Area of Science:

• Neuroscience
• Psychiatry
• Pharmacology

Background:

• Depression severity exists on a spectrum, with some patients experiencing severely treatment-resistant depression (TRD) unresponsive to multiple therapies.
• Identifying novel therapeutic targets for TRD is crucial for improving patient outcomes.

Purpose of the Study:

• To evaluate the safety and efficacy of psilocybin as a treatment for individuals diagnosed with severe TRD.
• To explore the relationship between psychedelic experiences and antidepressant response.

Main Methods:

• An open-label trial involving 12 participants (aged 18-65) with severe TRD.
• Participants received a single 25 mg dose of synthetic psilocybin, with psychotropic medications discontinued prior to and following dosing.
• Therapeutic support included pre-treatment, dosing day, and post-treatment integration sessions. Depression was assessed using the Montgomery-Åsberg Depression Rating Scale (MADRS).

Main Results:

• Significant reductions in MADRS scores were observed at 3 weeks (mean change -15.8) and 12 weeks (mean change -17.2) post-psilocybin administration.
• Exploratory analysis indicated a correlation between the 'Oceanic Boundlessness' aspect of the psychedelic experience and antidepressant response.
• Comorbid PTSD in five participants was associated with a diminished antidepressant effect of psilocybin.

Conclusions:

• The study suggests psilocybin is a safe and effective option for treating severe TRD.
• Further investigation into psychedelics for TRD is warranted, including understanding interactions with comorbid conditions like PTSD.