Single dose of LSD formulation improves anxiety in Phase 2b trial
The Brown University Psychopharmacology Update November 28, 2025 DOI: 10.1002/pu.31394 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Phase 2b clinical trial Peer reviewed |
|---|---|
| Population | Individuals with generalized anxiety disorder (GAD) |
| Topics | Anxiety LSD |
| Keywords | Phase matter Drug Pharmacology Anesthesia Clinical trial |
| Key findings | The two highest dose strengths of MM120 (LSD formulation) produced significant dose-dependent reductions in anxiety relative to placebo. |
Abstract
Treatment with a single dose of a pharmaceutical formulation of lysergic acid diethylamide (LSD) resulted in a dose‐dependent reduction in anxiety in individuals with generalized anxiety disorder (GAD), a Phase 2b study has found. The two highest of four tested dose strengths of the MM120 formulation demonstrated significant improvement relative to placebo.
In the evidence
This study is part of the evidence base for a synthesis in the library. Here is how each one recorded it.
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The two highest dose strengths of an LSD formulation produced significant dose-dependent reductions in anxiety relative to placebo.
Synthesized
Comparable studies
Other non-randomized and open-label trials on LSD for anxiety, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| SHORT-TERM EFFECTS OF LSD ON ANXIETY, ATTITUDES AND PERFORMANCE Normal adults, mostly professional research personnel | 1964 | Controlled trial | n = 29 |
| LSD microdosing in major depressive disorder: results from an open-label trial Participants with major depressive disorder, most taking antidepressant medication | 2025 | Open-label phase 2A trial | n = 19 |
| Evaluating the Potential of Microdosing 1cp-LSD for the Treatment of Canine Anxiety: A One-Month Case Study. A 13-year-old female dog with severe separation anxiety | 2025 | Pilot study, single-case study | n = 1 |
| MedCheck: Psilocybin for Depression, LSD for Anxiety, Donanemab, LSD, and More Patients with moderate to severe major depressive disorder | 2024 | Phase 2 clinical trial | n = 34 |