EGX-A is a serotonin 5-HT<sub>2A</sub> receptor agonist and putative serotonergic psychedelic which is under development for the treatment of depressive disorders. It acts as a full agonist of the serotonin 5-HT<sub>2A</sub> receptor, shows high selectivity (>100-fold) for the serotonin 5-HT<sub>2A</sub> receptor over the serotonin 5-HT<sub>2B</sub> receptor, is much more potent as a serotonin 5-HT<sub>2A</sub> receptor agonist than psilocin, produces the head-twitch response, a behavioral proxy of psychedelic effects, in rodents, and produces antidepressant-like effects in rodents. The drug is being developed by atai Life Sciences and EntheogeniX Biosciences. As of January 2024, it is in the preclinical research stage of development.