Psychedelic drugs such as LSD and psilocybin are showing promising efficacy in clinical trials for the treatment of mood and addictive disorders as well as providing a new tool for investigating altered states of consciousness in the human brain. As with other psychedelic compounds, LSD produces profound psychological effects, and possibly therapeutic effects via agonism of the 5-HT2A receptor.

Currently, the degree to which LSD occupies its primary site of action at each dose is unknown. As such, it is not known what doses of LSD should be considered low, medium or high for use in clinical trials. By using positron emission tomography and the novel radioligand CIMBI-36, an agonist at the 5-HT2A receptor, we will be able to establish the relation between LSD doses and % occupancy at this site.

This research will enable future research using LSD to administer doses based on empirical neuroscience. This will allow for greater precision in the development of LSD as a therapeutic drug and a neuroscientific tool.

Figure: Day by day description of the research elements from the LSD occupancy project. The primary outcome is in green, describing the PET scanning with CIMBI-36 that will allow elucidation of the dose-occupancy relation for LSD in the living human brain.

This project is performed by Principal Investigator Gitte Moos Knudsen, Senior Researcher Patrick Fisher and PhD student Drummond McCulloch.