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HealthyEarly Phase 1LSD-psiloNCT03604744

Direct Comparison of Altered States of Consciousness Induced by LSD and Psilocybin

A Early Phase 1 study testing LSD and Psilocybin in people with Healthy, run by University Hospital, Basel, Switzerland at 1 site in Switzerland.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

LSD (lysergic acid diethylamide) and psilocybin (the active substance in "magic mushrooms") are widely used for recreational purposes. Both substances are also increasingly used in psychiatric and psychological research to induce and investigate alterations in waking consciousness and associated brain functions… Read more about this study

Who is it for?
Ages 25 to 65 yearsHealthy volunteers can take part
Conditions the study is for
Healthy
What is being tested?
LSD and Psilocybin
Could I receive a placebo?
Yes, some participants may receive a placebo
How many people
28 participants
Where
1 siteSwitzerland
Study dates
27 Mar 2019to 15 Apr 2021
Phase
Early Phase 1
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 25 to 65 years
  • All sexes
  • Healthy volunteers accepted
  • Adult, Older adult

Who may be able to join

  • Age between 25 and 65 years.
  • 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.
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  • 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 18-29 kg/m2.

Who cannot join

  • Chronic or acute medical condition
  • Current or previous major psychiatric disorder
  • Psychotic disorder in first-degree relatives
  • Illicit substance use (with the exception of cannabis) more than 10 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)
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  • Use of medications that may interfere with the effects of the study medications (any psychiatric medications)
  • Tobacco smoking (>10 cigarettes/day)
  • Consumption of alcoholic drinks (>10/week)
  • Bodyweight < 50 kg

Trial locations and contacts

1 site in 1 country.

Switzerland1 site

  • Clinical Pharmacology & Toxicology, University Hospital Basel

    Basel, 4056

Other trials in Switzerland

About this study

Official title: Direct Comparison of Altered States of Consciousness Induced by LSD and Psilocybin in a Random-order Placebo-controlled Cross-over Study in Healthy Subjects

LSD (lysergic acid diethylamide) and psilocybin (the active substance in "magic mushrooms") are widely used for recreational purposes. Both substances are also increasingly used in psychiatric and psychological research to induce and investigate alterations in waking consciousness and associated brain functions (functional brain imaging, "model psychosis") . However, it has never been studied whether there are differences in the alterations in mind produced by these two substances. Both LSD and psilocybin are thought to induce hallucinations primarily via stimulation of the 5-HT2A receptor. However, there are differences in the receptor activation profiles between the two substances that may also induce different subjective effects. LSD potently stimulates the 5-HT2A receptor but also 5-HT2B/C, 5-HT1 and D1-3 receptors . Psilocin (the active metabolite of the prodrug psilocybin) also stimulates the 5-HT2A receptor but additionally inhibits the 5-HT transporter. In contrast to LSD, psilocybin has no affinity for D2 receptors. Both substances are used in neuroscience as pharmacological tools. However, there are no modern studies comparing these two substances directly within the same clinical study and research subjects and using validated psychometric tools. Therefore, the investigators will compare the acute effects of LSD, psilocybin and placebo.

Conditions
Healthy
Being tested
LSD, Psilocybin

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • LSDDrug

    LSD 0.1 mg per os, single dose

  • LSDDrug

    LSD 0.2 mg per os, single dose

  • PsilocybinDrug

    Psilocybin 15 mg per os, single dose

  • PsilocybinDrug

    Psilocybin 30 mg per os, single dose

Study groups in NCT03604744
Study groupRoleWhat they receive
LSD-100, LSD-200, Psilocybin-15, Psilocybin-30, PlaceboExperimentalCross-over within-subjects design with all treatment conditions, separated by a wash-out phase
Receives: Drug: LSD; Drug: Psilocybin
LSD-200, Psilocybin-15, Psilocybin-30, Placebo, LSD-100Placebo comparatorCross-over within-subjects design with all treatment conditions, separated by a wash-out phase
Receives: Drug: LSD; Drug: Psilocybin
Psilocybin-15, Psilocybin-30, Placebo, LSD-100, LSD-200Placebo comparatorCross-over within-subjects design with all treatment conditions, separated by a wash-out phase
Receives: Drug: LSD; Drug: Psilocybin
Psilocybin-30, Placebo, LSD-100, LSD-200, Psilocybin-15Placebo comparatorCross-over within-subjects design with all treatment conditions, separated by a wash-out phase
Receives: Drug: LSD; Drug: Psilocybin
Placebo, LSD-100, LSD-200, Psilocybin-15, Psilocybin-30Placebo comparatorCross-over within-subjects design with all treatment conditions, separated by a wash-out phase
Receives: Drug: LSD; Drug: Psilocybin

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Altered states of consciousness

    total 5D-ASC score (5-Dimensional Altered States of Consciousness Rating Scale)

    Measured: 18 Months

Secondary outcomes (9)

  1. Subjective effects assessed by VAS

    VAS (Visual analog scale)

    Measured: 18 Months

  2. Subjective effects assessed by AMRS scales

    AMRS scales (Adjective mood Rating scale)

    Measured: 18 Months

  3. Psychotomimetic effects

    ESI (Eppendorf Schizophrenia Inventory)

    Measured: 18 Months

  4. Mystical-type experiences assessed by SCQ

    SCQ (States of consciousness questionnaire)

    Measured: 18 Months

  5. Mystical-type experiences assessed by MS scales

    MS scales (Mysticism scale)

    Measured: 18 Months

  6. Effects on emotion processing

    FERT (Face Emotion Recognition Task)

    Measured: 18 Months

  7. Autonomic effects assessed by heart rate

    Heart rate

    Measured: 18 Months

  8. Autonomic effects assessed by blood pressure

    Blood pressure (diastolic and systolic)

    Measured: 18 Months

  9. Autonomic effects assessed by body temperature

    Body temperature

    Measured: 18 Months

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted27 Jul 2018
  2. Study start27 Mar 2019
  3. Primary completion10 Apr 2021
  4. Study completion15 Apr 2021

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Early Phase 1
Primary purpose
Basic science
Allocation
Randomised
Intervention model
Crossover
Masking
Quadruple blind
Who is masked
Participant, Care provider, Investigator, Outcomes assessor
Enrolment
28 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT03604744
Sponsor's protocol ID
BASEC 2018-00985
Acronym
LSD-psilo
Status last verified
Apr 2021
First submitted
19 Jul 2018
Last updated
27 Apr 2021
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Publications

  • Holze F, Becker AM, Kolaczynska KE, Duthaler U, Liechti ME. Pharmacokinetics and Pharmacodynamics of Oral Psilocybin Administration in Healthy Participants. Clin Pharmacol Ther. 2023 Apr;113(4):822-831. doi: 10.1002/cpt.2821. Epub 2022 Dec 31.

    PubMed 36507738

  • Holze F, Ley L, Muller F, Becker AM, Straumann I, Vizeli P, Kuehne SS, Roder MA, Duthaler U, Kolaczynska KE, Varghese N, Eckert A, Liechti ME. Direct comparison of the acute effects of lysergic acid diethylamide and psilocybin in a double-blind placebo-controlled study in healthy subjects. Neuropsychopharmacology. 2022 May;47(6):1180-1187. doi: 10.1038/s41386-022-01297-2. Epub 2022 Feb 25.

    PubMed 35217796

Questions about this trial

What is this clinical trial studying?

A Early Phase 1 study testing LSD and Psilocybin in people with Healthy, run by University Hospital, Basel, Switzerland at 1 site in Switzerland.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 10 inclusion and 10 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 27 Apr 2021. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Switzerland. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Early Phase 1 (sometimes called Phase 0) studies give a very small amount of a treatment to a few people, mainly to see how the body handles it.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Altered states of consciousness (time frame: 18 Months). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT03604744, which also lists 2 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 27 Apr 2021.

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