Lysergic acid diethylamide-assisted therapy in patients with anxiety with and without a life-threatening illness A randomized, double-blind, placebo-controlled Phase II study
This double-blind cross-over trial (n=42) finds that LSD (2x 200 μg) significantly reduced anxiety (STAI-G) scores up to three months after treatment. The patients, both with and without a life-threatening illness, also improved on measures of depression (HAM-D, BDI). Those with more subjective drug effects and mystical-type experiences had better outcomes.
Authors
- Felix Müller
- Patrick Dolder
- Matthias Liechti
Published
Abstract
Background
This study aimed to investigate the efficacy and safety of lysergic acid diethylamide (LSD)-assisted therapy in patients who suffered from anxiety with or without association to a life threatening illness.
Methods
The study is an investigator-initiated two-center trial that used a double-blind, placebo-controlled, two-period, random-order, crossover design with two sessions with either oral LSD (200 μg) or placebo per period. The primary endpoint was anxiety symptoms 16 weeks after the last treatment session, assessed by Spielberger’s State-Trait Anxiety Inventory-Global (STAI-G) score in 42 patients. Further outcome measures included ratings for depression symptoms (BDI [Beck Depression Inventory] and HAM-D-21 [Hamilton Depression Rating Scale]) and ratings for acute subjective drug effects. The outcomes for the first period, (between-subjects analysis) are primarily shown due to carry-over effects.
Results
LSD treatment resulted in significant reductions of STAI-G scores up to 16 weeks after treatment (least square mean (± SE) change from baseline difference = -16.2 (5.8), 95% CI=-27.8 to -4.5, d=-1.18, p=0.007). Similar effects were observed for ratings of comorbid depression on the HAM-D-21 (-7.0 (1.9), 95% CI=-10.8 to -3.2, d=-1.1, p=0.0004) and the BDI (-6.1 (2.6), 95% CI=-11.4 to -0.9, d=-0.72, p=0.02). Positive acute subjective drug effects and mystical-type experiences correlated with the long-term reductions in anxiety symptoms. Transient, mild, acute untoward effects of LSD treatment were reported by eight patients (19%). One treatment-related serious adverse event (acute transient anxiety) occurred (2%).
Conclusion
LSD produced long-lasting and notable reductions of anxiety and comorbid depression symptoms up to 16 weeks.
Research Summary of 'Lysergic acid diethylamide-assisted therapy in patients with anxiety with and without a life-threatening illness A randomized, double-blind, placebo-controlled Phase II study'
Introduction
Anxiety is common across psychiatric disorders and frequently accompanies life‑threatening illnesses (LTIs) such as cancer. Current treatments, principally selective serotonin reuptake inhibitors and psychotherapy, require ongoing administration and show limited efficacy for many patients, motivating investigation of alternative approaches. Classic psychedelics act primarily at the serotonin 5‑HT2A receptor and can produce profound acute alterations of consciousness and mystical‑type experiences; modern clinical research has focused largely on psilocybin, whereas LSD has been less rigorously studied in contemporary controlled trials despite historical use in patients with terminal illness. Holze and colleagues designed this trial to evaluate whether LSD‑assisted therapy produces clinically meaningful and sustained reductions in anxiety and related symptoms in patients with anxiety both with and without an associated life‑threatening illness. The investigators hypothesised that two high‑dose LSD sessions would reduce anxiety at 16 weeks after treatment and that acute subjective effects measured with established scales (5D‑ASC and MEQ30) would correlate with longer‑term therapeutic benefit.
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Study Details
- Study Typeindividual
- Journal
- Compound
- Topics
- Authors
- APA Citation
Holze, F., Gasser, P., Müller, F., Dolder, P. C., & Liechti, M. E. (2023). Lysergic acid diethylamide-assisted therapy in patients with anxiety with and without a life-threatening illness A randomized, double-blind, placebo-controlled Phase II study. Biological Psychiatry, 93(3), 215-223. https://doi.org/10.1016/j.biopsych.2022.08.025
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