Clinical TrialHealthy VolunteersLSDMDMAPlaceboCompleted

Role of Dopamine, Serotonin and 5-HT2A Receptors in Emotion Processing

Randomised, quadruple-blind, crossover study (n=28) of single oral doses of LSD (100 µg), MDMA (125 mg) and d‑amphetamine (40.3 mg) versus placebo in healthy volunteers to assess emotion processing and fMRI amygdala responses.

Target Enrollment
28 participants
Study Type
Phase I interventional
Design
Randomized, quadruple Blind

Detailed Description

This randomized, quadruple-blind crossover study administers single oral doses of LSD, MDMA, d‑amphetamine and placebo to healthy adult volunteers to probe the roles of dopamine, serotonin and 5‑HT2A receptors in emotion processing.

Primary assessments include behavioural measures of empathy and mood perception alongside fMRI measures of amygdala activity to fearful stimuli; associations between subjective effects and imaging will be explored.

Each participant receives four single-dose sessions separated by washout; safety, vitals and adverse events are monitored throughout.

Study Protocol

Preparation

sessions

Dosing

4 sessions

Integration

sessions

Study Arms & Interventions

Crossover

experimental

Within-subject crossover: placebo, LSD 100 µg, MDMA 125 mg, d-amphetamine 40.3 mg (each single oral dose; sessions separated by washout).

Interventions

  • LSD100 µg
    via Oral• single dose

    100 µg per os

  • MDMA125 mg
    via Oral• single dose

    125 mg per os

  • Compound40.3 mg
    via Oral• single dose

    d-amphetamine sulfate 40.3 mg per os

  • Placebo
    via Oral• single dose

    Mannitol capsules identical appearance

Participants

Ages
25 – 50
Sexes
Male & Female

Inclusion Criteria

  • Age between 25 and 50 years.
  • Sufficient understanding of the German language.
  • Subjects understand the procedures and the risks and consent to participate.
  • Willing to refrain from illicit psychoactive substances during the study.
  • Willing to drink only alcohol-free liquids and avoid coffee, black/green tea, or energy drinks after midnight before study sessions and on study days.
  • Willing not to drive or operate machines within 48 h after substance administration.
  • Women of childbearing potential must have a negative pregnancy test at baseline and before each session; participants agree to effective contraception.
  • Body mass index 18-29 kg/m2.

Exclusion Criteria

  • Chronic or acute medical condition.
  • Hypertension (>140/90 mmHg) or hypotension (SBP <85 mmHg).
  • Current or previous major psychiatric disorder.
  • Psychotic disorder in first-degree relatives.
  • Illicit substance use (except cannabis) more than 10 times lifetime or any use within the previous two months.
  • Pregnant or nursing women.
  • Participation in another clinical trial currently or within the last 30 days.
  • Use of medications that may interfere with study medications (including psychiatric medications).
  • fMRI-related contraindications (metal implants, cochlear implants, large neck tattoos, etc.).
  • Tobacco smoking >10 cigarettes/day.
  • Alcohol consumption >10 drinks/week.

Study Details

  • Status
    Completed
  • Phase
    Phase I
  • Type
    interventional
  • Design
    Randomizedquadruple Blind
  • Target Enrollment28 participants
  • Timeline
    Start: 2017-01-02
    End: 2018-04-09
  • Compounds
    LSDMDMAPlacebo
  • Topic
    Healthy Volunteers

Locations

University Hospital Basel — Basel, Canton of Basel-City, Switzerland

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