RCT · 2025
First human trial of GM-2505, a new short-acting psychedelic drug, in 48 healthy volunteers
- Original title
- A novel psychedelic 5-HT2A receptor agonist GM-2505: The pharmacokinetic, safety, and pharmacodynamic profile from a randomized trial healthy volunteer.
- Authors
- Marek GJ, Makai-Bölöni S, Umbricht D, et al.
- Journal
- Journal of psychopharmacology (Oxford, England), 2025
- Molecules
- Other
- Conditions
- Healthy volunteers
- Participants
- 48
- Evidence grade
- Moderate
- Source
- Read the original paper
The question
Is GM-2505, a new drug that acts on the same brain receptor as psilocybin and DMT, safe and tolerable in healthy people, and how long do its effects last?
What they did
Researchers ran a single-ascending-dose study: groups of healthy volunteers received one intravenous dose of GM-2505 or a placebo, with neither participants nor staff knowing which. In total 48 healthy participants took part. The team tracked side effects, heart tracings, blood pressure, blood levels of the drug, hormones, brain electrical activity (EEG), and self-reported drug effects.
What they found
Single intravenous doses up to 20 mg had what the authors called an acceptable safety profile, with mild, passing side effects and short-lived rises in blood pressure and pulse that were not judged clinically significant. There were no significant changes on electrocardiograms. Blood levels rose roughly in proportion to dose, and the drug cleared quickly, with a half-life of 40-50 minutes. Effects on hormones, thinking and brain measures, and subjective experience increased with dose; resting EEG showed less power in slower theta and alpha bands and more in faster gamma bands. The authors suggested an optimal dose range of 10-15 mg intravenously, with effects shorter than psilocybin but longer than DMT.
The fine print
This was an early-stage safety study in healthy volunteers, so it says nothing about whether GM-2505 helps depression. The sample of 48 was split across several dose groups, making each group small, and follow-up was short. Brain and hormone measures are indirect markers, not clinical outcomes. This summary is based on the abstract alone.
What it means
A new psychedelic-type compound passed an early human safety check and produced dose-related effects that faded faster than psilocybin’s, but whether it treats depression remains untested.
Evidence grade: Moderate. A randomized, double-blind, placebo-controlled first-in-human safety study, but small, in healthy volunteers only, and it measured drug effects rather than treatment of any illness.
This summary is based on the study’s published abstract.