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.
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 |