Acute Effects of 2C-B Compared With MDMA and Psilocybin in Healthy Subjects

NCT05523401 | Completed Phase 1

• 1 other identifier: BASEC 2022-00355
• Study Type: interventional
• Target: 24
• Locations: 1 country
• Sites: 1

Brief Summary

4-bromo-2,5-dimethoxyphenethylamine (2C-B) is a psychoactive substance with reportedly similar acute effects to both the prototypical empathogen 3,4-methylenedioxymethamphetamine (MDMA, Ecstasy) and the classic psychedelic substance psilocybin (contained in "magic, hallucinogenic mushrooms"). Pharmacologically, MDMA mainly releases serotonin (5-HT) via the serotonin transporter (SERT) and psilocybin mainly acts as direct agonist at 5-HT2A receptors. 2C-B interacts with both the 5-HT2A receptor and SERT which is in line with its reported mixed effects profile. However, scientific studies are lacking. There is an increased interest in psychiatric research on the therapeutic properties of MDMA and psilocybin and also on mixed empathogenic-psychedelic substances.

Conditions

Healthy

Outcome Measures

Primary Outcomes (1)

• Acute subjective effects I

  5 Dimensions of Altered States of Consciousness (5D-ASC) consisting of 94 items to be rated on a visual analog scale (0-100 mm), with higher values indicating stronger effects with higher scores representing more intense effects. Assessed once at the end of the session, 9h after substance administration.

  18 months

Secondary Outcomes (18)

• Acute subjective effects II

  18 months

• Acute subjective effects III

  18 months

• Autonomic effects I

  18 months

• Autonomic effects II

  18 months

• Autonomic effects III

  18 months

Study Arms (6)

10 mg 2C-B

EXPERIMENTAL

2C-B (10 mg)

Drug: 4-bromo-2,5-dimethoxyphenethylamine (10 mg)

20 mg 2C-B

EXPERIMENTAL

2C-B (20 mg)

Drug: 4-bromo-2,5-dimethoxyphenethylamine (20 mg)

30 mg 2C-B

EXPERIMENTAL

2C-B (30 mg)

Drug: 4-bromo-2,5-dimethoxyphenethylamine (30 mg)

125 mg MDMA

ACTIVE COMPARATOR

MDMA (125 mg)

Drug: 3,4-methylenedioxymethamphetamine

25 mg Psilocybin

ACTIVE COMPARATOR

Psilocybin (25 mg)

Drug: Psilocybin

Placebo

PLACEBO COMPARATOR

Placebo

Other: Placebo

Interventions

4-bromo-2,5-dimethoxyphenethylamine (10 mg) DRUG

A low dose of 10 mg 2C-B will be administered.

Also known as: 2C-B

10 mg 2C-B

4-bromo-2,5-dimethoxyphenethylamine (20 mg) DRUG

A medium dose of 20 mg 2C-B will be administered.

Also known as: 2C-B

20 mg 2C-B

4-bromo-2,5-dimethoxyphenethylamine (30 mg) DRUG

A high dose of 30 mg 2C-B will be administered.

Also known as: 2C-B

30 mg 2C-B

3,4-methylenedioxymethamphetamine DRUG

A moderate dose of 125 mg MDMA will be administered.

Also known as: MDMA

125 mg MDMA

Psilocybin DRUG

A moderate dose of 25 mg psilocybin will be administered.

25 mg Psilocybin

Placebo OTHER

Placebo (Mannitol)

Placebo

Eligibility Criteria

• Age: 25 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age between 25 and 65 years.
• Sufficient understanding of the German language.
• Understanding the procedures and the risks that are associated with the study.
• Participants must be willing to adhere to the protocol and sign the consent form.
• Participants must be willing to refrain from taking illicit psychoactive substances during the study.
• Participants must be willing to drink only alcohol-free liquids and no coffee, black or green tea, or energy drink after midnight of the evening before the study session, as well as during the study day.
• Participants must be willing not to drive a traffic vehicle or to operate machines within 48 h after substance administration.
• Women of childbearing potential must have a negative pregnancy test at the beginning of the study. Pregnancy tests are repeated before each study session.
• Women of childbearing potential must be willing to use double-barrier birth control.
• Body mass index between 18-29kg/m2

You may not qualify if:

• Chronic or acute medical condition, including a history of seizures.
• Current or previous major psychiatric disorder (e.g. psychotic disorders, mania / hypomania, anxiety disorders).
• Psychotic or bipolar disorder in first-degree relatives, not including psychotic disorders secondary to an apparent medical reason, e.g. brain injury, dementia, or lesions of the brain.
• Hypertension (SBP\>140/90 mmHg) or hypotension (SBP\<85 mmHg)
• Ilicit substance use (with the exception of cannabis) more than 20 times or any time 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 the effects of the study medications (any psychiatric medications and any medication with known to interact with the study substances).
• Tobacco smoking (\>10 cigarettes/day).
• Consumption of alcoholic drinks (\>20 drinks / week).
• Body weigt \< 45 kg.

Sponsors & Collaborators

• University Hospital, Basel, Switzerland: lead

Study Sites (1)

University Hospital Basel

Basel, Switzerland

Location

MeSH Terms

Interventions

2-(4-bromo-2,5-dimethoxyphenyl)ethylamine; N-Methyl-3,4-methylenedioxyamphetamine; Psilocybin

Intervention Hierarchy (Ancestors)

Amphetamines; Phenethylamines; Ethylamines; Amines; Organic Chemicals; Indole Alkaloids; Alkaloids; Heterocyclic Compounds; Indoles; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Tryptamines; Indolizidines; Indolizines

Study Officials

• Matthias E Liechti, MD

  University Hospital, Basel, Switzerland

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: 6-period random order, placebo-controlled, double-blind, cross-over study with five active substance conditions and placebo: 1\. 2C-B (10 mg), 2. 2C-B (20 mg), 3. 2C-B (30 mg), 4. MDMA (125 mg), 5. Psilocybin (25 mg), 6. Placebo

Study Record Dates

• First Submitted: August 29, 2022
• First Posted: August 31, 2022
• Study Start: August 16, 2023
• Primary Completion: October 20, 2024
• Study Completion: November 5, 2024
• Last Updated: March 5, 2025

Record last verified: 2025-02

Locations

CH (1)