Alcohol use causes more overall harm than any other drug and is the seventh leading risk factor for both deaths and disability-adjusted life years. Alcohol use disorders (AUD) are among the most common and undertreated mental disorders in developed countries. Pharmacological and psychotherapeutic treatments only show limited efficacy, and around 60% of the patients relapse in the short term after withdrawal. Lysergic acid diethylamide (LSD) was investigated in numerous clinical trials during the 1950s and 1960s. Specifically, the use of LSD in the treatment of AUD was investigated extensively. A pooled analysis of six historical clinical trials demonstrated that a single dose of LSD significantly reduced alcohol use at three and six months after LSD administration. However, these trials are limited by several factors, including the use of diagnostic standards that are no longer up to date, single, high-dose treatment regimes, missing biological assessment for alcohol use, and no consequent assessment of blinding. This trial will assess the efficacy and safety of two moderate to high doses of LSD to decrease alcohol consumption in patients with AUD. The trial has a double-blind, active placebo-controlled, randomized, parallel design and will be conducted in specialized treatment centers for addictive disorders in Switzerland. The study will include 128 patients who have undergone detoxification. Participants will be allocated to one of the two intervention arms (1:1 allocation). Each arm comprises nine study visits (no drug administration) and two study days (involving LSD administration) within 30 weeks. Patients allocated to the control intervention (active placebo group) will receive 10 µg LSD on the first study day and either 10 or 20 µg LSD on the second study day. Patients allocated to the treatment intervention will receive 150 µg LSD on the first study day and either 150 µg or 250 µg LSD on the second study day. The dose will be retained or increased depending on the patient's individual response on the first study day. Participants in the control intervention will be offered to attend an open-label LSD session (150 µg) at week 31. The open-label phase will comprise three additional visits. This trial will further compare the effectiveness of LSD-assisted therapy in both group and individual therapeutic settings. To this end, participants in both drug conditions will be randomly assigned to group or individual settings. The primary outcome is the mean of percent heavy drinking days after administration of two doses of LSD during the 12 weeks following the second administration. Secondary objectives: The second aim of this study is to explore long-term changes in the cortical thickness, white matter microstructure, resting state functional connectivity (rs-FC) and cerebral blood flow (CBF) of regions associated with addiction pathophysiology. Furthermore, we will assess alterations in depressive symptoms, anxiety, and persisting effects of LSD. We will also assess biological markers of alcohol use and several predictors for treatment-response (genetics, personality traits, blinding, expectancy, and quality of acute drug effects). Lastly, we will compare LSD treatment within a group setting with treatment within an individual setting.
Patients will be followed up six months after the second administration in the double-blind phase. At this time point, a predefined subset of the questionnaires used in the main study will be administered (TLFB, SIP-2R, OCDS, drinking goals, self-efficacy, BSCL, BDI, and BAI; see below). During the open-label phase, patients will be assessed one month after administration. This assessment will include a subset of questionnaires (TLFB, OCDS, BSCL, BAI, BDI, CHIME, WHOQOL-BREF, drinking goals, self-efficacy, and WVQ; see below). In addition, the open-label phase will include assessments of acute drug effects, expectancy, and adverse events (see below).
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
QUADRUPLE
Enrollment
128
Moderate to high dose LSD
Low dose LSD
University Hospital of Psychiatry, University of Basel
Basel, Switzerland
RECRUITINGUniversity Hospital of Psychiatry, University of Bern
Bern, Switzerland
RECRUITINGPercent heavy drinking days
The primary outcome is the mean percentage of heavy drinking days after administration of two doses of LSD assessed with the alcohol timeline follow-back (TLFB) questionnaire compared between treatment groups
Time frame: Period of three months after the second administration
Cortical thickness measured with MRI
Changes in the cortical thickness of the ACC, PCC, and PFC
Time frame: One month after the first administration, one month after second administration
The volume of the striatum measured with MRI
Changes in the volume of the striatum
Time frame: One month after the first administration, one month after second administration
White matter microstructure measured with MRI
Changes in white matter microstructure in the cingulum bundle and the PFC-striatal connection pathway
Time frame: One month after the first administration, one month after second administration
Days to first heavy drinking day
Days to first heavy drinking day after the first and second administration assessed with TLFB
Time frame: One month after the first administration, one, two, and three months after the second administration
Days to first drinking day
Days to first drinking day assessed after the first and second administration assessed with TLFB
Time frame: One month after the first administration, one, two, and three months after the second administration
Percent days abstinent
Percent days abstinent after the first and second administration assessed with TLFB
Time frame: One month after the first administration, one, two, and three months after the second administration
Drinks per drinking day
Drinks per drinking day after the first and second administration assessed with TLFB
Time frame: One month after the first administration, one, two, and three months after the second administration
Percent heavy drinking days
Percent heavy drinking days assessed with TLFB
Time frame: One month after the first administration
Adverse consequences of alcohol use
Adverse consequences of alcohol use assessed with the Short Inventory of Problems (SIP-2R) questionnaire
Time frame: Three months after the second administration
Craving
Craving assessed with the Obsessive Compulsive Drinking Scale (OCDS)
Time frame: Three weeks after the first administration, three weeks, two and three months after the second administration
Ethyl glucuronide
Ethyl glucuronide (EtG) in hair
Time frame: Three months after the second administration
Phosphatidylethanol
Phosphatidylethanol (PEth) in blood
Time frame: At each administration and three months after the second administration
Perceived quality of life across multiple domains
Quality of life assessed with the World Health Organization Quality of Life Scale (WHOQOL-bref)
Time frame: One and two months after the second administration
Depression
Beck Depression Inventory (BDI)
Time frame: Three weeks after the first administration, one and three months after the second administration
Anxiety
Beck Anxiety Inventory (BAI)
Time frame: Three weeks after the first administration, one and three months after the second administration
Various somatic and psychological symptoms
Various somatic and psychological symptoms assessed with the Brief Symptom Checklist (BSCL)
Time frame: Three weeks after the first administration, one and three months after the second administration
World view
World views will be assessed using the World View Questionnaire (WVQ)
Time frame: Three weeks after the first administration, three weeks after the second administration
Persisting effects
Persisting effects of LSD assessed with the Persisting Effects Questionnaire (PEQ)
Time frame: Three months after the second administration
Mindfulness
Mindfulness will be assessed using the Comprehensive Inventory of Mindfulness Experience (CHIME)
Time frame: Three weeks after the first administration, three weeks after the second administration, two months after the second administration
Acute effects of LSD
Acute effects assessed with the 5 Dimensions of Altered States of Consciousness (5D-ASC)
Time frame: The day after the first and the day after the second administration
Acute effects of LSD
Acute effects assessed with the Mystical Experience Questionnaire (MEQ30)
Time frame: The day after the first and the day after the second administration
Acute effects of LSD
Acute effects assessed with the General Change Mechanisms Questionnaire (GCMQ)
Time frame: The day after the first and the day after the second administration
Acute effects of LSD
Acute effects assessed with the Phenomenological-Autobiographical-Existential Psychedelic Scale extended (PAE-PS-ext)
Time frame: The day after the first and the day after the second administration
Blinding
Blinding will be assessed directly after session 1 with a self-developed questionnaire that includes participants' guesses of their group assignment and their degree of certainty, rated on a visual analogue scale.
Time frame: In the evening after the first administration
Expectancy
Expectancy will be assessed with the Credibility / Expectancy Questionnaire (CEQ). Therapists' expectancy will also be assessed
Time frame: Two weeks before the first administration
Self-efficacy
Self-efficacy will be assessed using a visual analogue scale
Time frame: Three weeks after the first administration, three weeks after the second administration, two and three months after the second administration
Drinking goals
Drinking goals will be assessed using pre-defined response options
Time frame: Three weeks after the first administration, three weeks after the second administration, two and three months after the second administration
Safety: Adverse events
Adverse events will be documented at each visit and each session.
Time frame: Week 0 to week 18
Qualitative Interview
Qualitative interview regarding subjective experiences of acute drug effects, benefits, possible negative effects, as well as the subjective concept of the potential psychological mechanisms
Time frame: Three months after the second administration
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