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Valentyne Sobolenko

3 papers in the library · 1 citation · publishing 2025-2026

Papers

Microdosing psilocybin for major depressive disorder: study protocol for a phase II double-blind placebo-controlled randomised partial crossover trial

BJPsych Open February 16, 2026 Zeina Beidas, Anya Ragnhildstveit, Adam Blackman et al. 1 citation

This is a protocol for a phase II trial testing whether very low doses of psilocybin (2 mg, a microdose) can safely and effectively treat major depressive disorder. Forty adults with MDD will receive either psilocybin or a placebo once weekly for four weeks, then all will receive psilocybin for another four weeks. The trial will measure changes in depression symptoms, mood, well-being, attention, creativity, mindfulness, and pro-sociality. Results will be published regardless of outcome. The findings are expected to guide future research on dose regimens, effect sizes, and the role of expectancy bias, and to inform debates about sub-threshold versus threshold doses of psilocybin.

DOI: 10.1192/bjo.2025.10968 Full text

Microdosing psilocybin for major depressive disorder: study protocol for a phase II double-blind placebo-controlled randomised partial crossover trial - CORRIGENDUM.

BJPsych Open May 13, 2026 Zeina Beidas, Anya Ragnhildstveit, Adam Blackman et al.

This is a correction notice for a previously published study protocol. The original protocol describes a phase II double-blind placebo-controlled randomised partial crossover trial investigating microdosing psilocybin for major depressive disorder. No new findings or data are presented.

DOI: 10.1192/bjo.2026.12000 Full text

Microdosing Psilocybin for Major Depressive Disorder: Study Protocol for a Phase II Double-Blind Placebo-Controlled Randomized Partial Crossover Trial

November 16, 2025 Zeina Beidas, Anya Ragnhildstveit, Adam Blackman et al. preprint

A phase II trial will test whether microdosing psilocybin (2 mg weekly) outperforms placebo for major depressive disorder. Forty adults will receive either psilocybin or placebo for four weeks, then all will receive psilocybin for another four weeks. Depression symptoms and other measures will be assessed at baseline, after four weeks, and after eight weeks, with follow-ups for two years. The study aims to clarify whether microdosing has genuine antidepressant effects or whether benefits are due to expectancy, and to inform future dose regimens and the therapeutic role of sub-threshold versus threshold doses.

DOI: 10.31234/osf.io/hmnsw_v1 Psilocybin Major depressive disorder Anxiety Placebo +15