Clinical Research

The modern clinical trial era for psilocybin began in earnest at Johns Hopkins in 2006, when Roland Griffiths and colleagues published the first rigorously controlled study of psilocybin's mystical effects in healthy volunteers. That paper, demonstrating that 67% of participants rated the experience as one of the five most meaningful of their lives — with effects measured 14 months later — reopened a scientific conversation that had been closed for 30 years.

What followed was an accelerating cascade of phase 1 and phase 2 trials that has now produced the most robust evidence base in psychiatry for any single compound in decades. Johns Hopkins researchers showed psilocybin-assisted therapy produced greater than 50% reduction in depression scores in 71% of participants with major depressive disorder, with remission sustained at 12-month follow-up. COMPASS Pathways completed a 233-patient phase 2b trial across 22 sites, demonstrating dose-dependent efficacy for treatment-resistant depression with a clean safety profile. NYU and Johns Hopkins jointly published the landmark tobacco cessation study showing 80% abstinence at six months — triple the rate of the best pharmacological alternatives.

The regulatory landscape has moved accordingly. The FDA granted Breakthrough Therapy Designation to psilocybin for treatment-resistant depression (2018) and major depressive disorder (2019) — the first psychedelic to receive that status. Phase 3 trials are now underway. Australia became the first country to approve psilocybin for clinical use in February 2023. Oregon's Measure 109 created a licensed facilitation framework. The question has shifted from "does it work?" to "how do we scale it safely?"

The clinical evidence articles in this collection cover the full arc: mechanism of action, trial design methodology, patient selection, therapeutic protocol specifics, and outcomes data. We track the literature as it evolves, with particular attention to long-term follow-up data — where psilocybin's effects consistently demonstrate durability that distinguishes it from conventional antidepressants requiring daily dosing.