A Study Assessing Brain Activity, Safety, Tolerability, and Pharmacokinetics Following Multiple Doses of MLS101 (Psilocybin) in Healthy Volunteers

This Phase I randomised, single-blind trial (n=20) will study the effects of multiple low doses of psilocybin (MLS101) on brain activity, safety, tolerability, and pharmacokinetics in healthy adult volunteers.

Sponsored by MycoMedica Life Sciences PBC and conducted at Hammersmith Medicines Research in London, this early-stage study aims to explore whether repeated low doses of psilocybin—below the threshold for full psychedelic effects—can safely influence brain function in ways that may be beneficial for future treatment of chronic psychiatric conditions such as premenstrual dysphoric disorder (PMDD), obsessive-compulsive disorder (OCD), and opioid use disorder. Participants will receive either psilocybin or a placebo in capsule form over multiple sessions, and their brain activity will be assessed using functional magnetic resonance imaging (fMRI).

In addition to imaging, researchers will measure subjective effects using established tools like the Mystical Experience Questionnaire (MEQ30), the 5-Dimensional Altered States of Consciousness scale (5D-ASC), and the Acute Subjective Effects Scale (ASES). Cognitive function will also be evaluated through tasks such as the Digit Symbol Substitution Test (DSST) and Trail Making Test A. The trial will collect detailed data on how psilocybin is processed in the body (pharmacokinetics) including how long it stays in the system and how intensely it is experienced. This study is part of a broader effort to understand the therapeutic potential of low-dose psychedelics and inform future trials targeting mental health disorders.

Topic Healthy Subjects Safety Neuroscience
Compound Psilocybin Placebo
Country United Kingdom
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