Systematic review · 2025
A review of 241 registered psychedelic clinical trials and how the field has changed
- Original title
- Landscape analysis of pre-registered clinical trials involving classical psychedelics.
- Authors
- Uyar A, Forbrich L, Lueken U, et al.
- Journal
- Journal of psychopharmacology (Oxford, England), 2025
- Molecules
- Psilocybin, LSD, DMT, 5-MeO-DMT
- Conditions
- Other
- Evidence grade
- Low
- Source
- Read the original paper
The question
How many clinical trials of classical psychedelics have been registered, which substances and study designs do they use, and how has that changed over time?
What they did
The authors searched ClinicalTrials.gov on 11 November 2024 for registered interventional trials testing serotonergic (“classic”) psychedelics such as LSD, psilocybin and DMT or 5-MeO-DMT. They summarized study characteristics and used a statistical model to look at registration trends over time. They also looked at who ran the trials, where they took place, and how well any psychotherapy component was described.
What they found
They identified 241 registered trials. Registrations rose sharply after 2006 and sped up again after 2019, and two-thirds of the trials are still ongoing or planned. Psilocybin was the most studied substance and the furthest along towards regulatory approval, while shorter-acting psychedelics such as DMT and 5-MeO-DMT have been introduced more recently with a narrower clinical focus. Industry sponsorship is increasing, though university-led research still dominates. Mentions of psychotherapy components rose after 2023 FDA recommendations, but the authors saw no clear improvement in how those components were described.
The fine print
This is a snapshot of one registry (ClinicalTrials.gov) at a single date, so trials registered elsewhere or never registered are missed. Registry entries can be incomplete or out of date, and the analysis describes plans and paperwork rather than results, safety or effectiveness. This summary is based on the abstract only.
What it means
Psychedelic research is expanding quickly and shifting towards industry-led, approval-focused trials, but the way trials describe their therapy components remains inconsistent, which makes it hard to compare studies.
Evidence grade: Low. This is a descriptive review of trial registry entries, not a study measuring health outcomes in people, so it can describe the shape of the field but not whether treatments work.
This summary is based on the study’s published abstract.