A Phase 1 interventional study of Psilocybin and Placebo in Healthy Volunteers, sponsored by MycoMedica Life Sciences PBC. Completed at 1 site in Australia. Open to participants aged 18 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-06-12.
Sponsored by MycoMedica Life Sciences PBC · Phase 1, Interventional, and Treatment
MLS101 is being developed as a low dose psilocybin, that can be administered to treat neurological and psychiatric conditions.
The purpose of this clinical trial is to assess how safe and tolerated MLS101 is; to see how MLS101 is distributed and cleared by the body (pharmacokinetics); and to assess the psychedelic effects of MLS101 in healthy, adult participants.
In recent years, high-dose psilocybin has gained attention for it potential therapeutic benefit in many psychiatric conditions, however existing clinical data for low psilocybin doses are limited.
Microdoses are generally considered to be those absent of profound sensory and cognitive effects that would interfere with normal everyday functioning, but only a small number of prospective studies have evaluated microdoses and/or low doses in a controlled manner.
As a foundational study of the therapeutic use of psilocybin microdoses, this study will assess the safety, tolerability, pharmacokinetics and sensorial effects using a prospective, controlled, multiple dose regimen in healthy volunteers.
MycoMedica Life Sciences PBC is the lead sponsor of 4 studies on the registry; 1 is open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
MLS101 capsule(s) administered orally as a once a day dose
Drug: Psilocybin
Active treatment matching capsules will be administered orally as a once a day dose
Drug: Placebo
Capsule containing active ingredient, psilocybin
Also known as: MLS101
Capsule with no active ingredients
Incidence, severity and seriousness of treatment-emergent adverse events (TEAEs)
Physical examinations, safety laboratory tests, ECGs
Time frame: Screening (Day -28) to end of study visit (Cohort 1: Day 15; Cohort 2: Day 23)
Occurrence of clinically significant changes in physical examination, vital signs, ECGs, clinical laboratory tests, the Columbia-Suicide Severity Rating Scale (C-SSRS).
The Columbia Suicide Severity Rating Scale (C-SSRS) is a short questionnaire. If there is a positive result for suicidality on the C-SSRS after Screening (defined by a participant answering "yes" to questions 4 or 5 on the suicidal ideation portion of the C-SSRS), the participant will be evaluated by an Investigator or medically qualified Sub-investigator for continuation in the study. Participants with suicidal ideation or behaviour (a "yes" answer at any time during treatment to any one of the ten suicidal ideation and behaviour questions (Categories 1-10) on the C-SSRS) at any time during the study will be withdrawn from the study. If a participant becomes suicidal during the study, an Investigator or medically qualified Sub-investigator should provide the appropriate treatment to the participant.
Time frame: Screening (Day -28) to end of study visit (Cohort 1: Day 15; Cohort 2: Day 23)
Pharmacokinetics of MLS101: maximum observed serum concentration (Cmax)
Blood sample collections
Time frame: Day 1 to Day 8 pre-dose, Day 1 to Day 9 post-dose (Cohort 1); Day 1 to Day 16 pre-dose, Day 1 to Day 17 post-dose (Cohort 2)
Pharmacokinetics of MLS101: area under the plasma concentration-time curve (AUC)
Blood sample collections
Time frame: Day 1 to Day 8 pre-dose, Day 1 to Day 9 post-dose (Cohort 1); Day 1 to Day 16 pre-dose, Day 1 to Day 17 post-dose (Cohort 2)
Pharmacokinetics of MLS101: time corresponding to the occurrence of Cmax (Tmax)
Blood sample collections
Time frame: Day 1 to Day 8 pre-dose, Day 1 to Day 9 post-dose (Cohort 1); Day 1 to Day 16 pre-dose, Day 1 to Day 17 post-dose (Cohort 2)
Pharmacokinetics of MLS101: apparent terminal elimination half-life (t½)
Blood sample collections
Time frame: Day 1 to Day 8 pre-dose, Day 1 to Day 9 post-dose (Cohort 1); Day 1 to Day 16 pre-dose, Day 1 to Day 17 post-dose (Cohort 2)
Pharmacokinetics of MLS101: apparent total systemic clearance after oral administration (CL/F)
Blood sample collections
Time frame: Day 1 to Day 8 pre-dose, Day 1 to Day 9 post-dose (Cohort 1); Day 1 to Day 16 pre-dose, Day 1 to Day 17 post-dose (Cohort 2)
Pharmacokinetics of MLS101: apparent volume of distribution during the terminal phase (Vz/F)
Blood sample collections
Time frame: Day 1 to Day 8 pre-dose, Day 1 to Day 9 post-dose (Cohort 1); Day 1 to Day 16 pre-dose, Day 1 to Day 17 post-dose (Cohort 2)
Sensorial effects of MLS101
Using validated questionnaires, the nominal sensorial threshold dose of MLS101 will be identified. The nominal sensorial threshold dose is defined as the highest dose studied that is absent of clinically significant sensorial effects, and which would not interfere with the participant's ability to carry on with routine activities of daily living. Higher scores indicate presence of sensorial effects.
Time frame: Day 1 to Day 8 pre- and post-dose (Cohort 1); Day 1 to Day 16 pre- and post-dose (Cohort 2)
Cognitive function: Digit Symbol Substitution Test (DSST)
The test taker's score is the number of correct symbol-to-number matches they complete within the allotted time.
Time frame: Pre-dose (Day -1), Day 1, Day 4 and Day 8 (Cohort 1); Pre-dose (Day -1), Day 1, Day 4 and Day 16 (Cohort 2)
Cognitive Function: Stroop Color and Word Test (SCWT)
Participants read tables of words and colors as quickly as possible.
Time frame: Pre-dose (Day -1), Day 1, Day 4 and Day 8 (Cohort 1); Pre-dose (Day -1), Day 1, Day 4 and Day 16 (Cohort 2)
Cognitive function: Trail Making Test A (TMT-A)
The participant draws lines to connect circled numbers in an ascending pattern (i.e., in numerical sequence 1-2-3, etc.) as rapidly as possible. The score is the time it takes the participant to complete the task in seconds.
Time frame: Pre-dose (Day -1), Day 1, Day 4 and Day 8 (Cohort 1); Pre-dose (Day -1), Day 1, Day 4 and Day 16 (Cohort 2)
This study is completed, as verified in Jun 2025. You cannot join it, but the record below documents what was studied.
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MycoMedica Life Sciences PBC