TRALA-12, also known as N-ethenyl-N-ethyllysergamide or as lysergic acid vinylethylamide, is a serotonin receptor modulator and possible psychedelic drug of the lysergamide family related to lysergic acid diethylamide (LSD). It is the analogue of LSD in which one of the ethyl groups on the amide has been replaced with an ethenyl (vinyl) group. Didehydro-LSD (DDH-LSD), which is structurally and pharmacologically compatible with TRALA-12, is being developed by Matthias Liechti and colleagues as a shorter-lasting LSD analogue for potential medical use.
Pharmacology Pharmacodynamics TRALA-12 is a potent agonist of the serotonin 5-HT2 receptors similarly to LSD. Its affinities (Ki) were 0.09nM for the serotonin 5-HT2A receptor, 0.67nM for the serotonin 5-HT2B receptor, and 3.8nM for the serotonin 5-HT2C receptor. Conversely, its activational potencies and efficacies ( ()) were 0.93nM (79%) at the serotonin 5-HT2A receptor and 1.7nM (42%) at the serotonin 5-HT2B receptor, whereas values for the serotonin 5-HT2C receptor were not reported. TRALA-12 showed 19-fold higher affinity for the serotonin 5-HT2A receptor than LSD, though it had only 1.5-fold higher activational potency at the receptor and had slightly lower efficacy ( = 79% and 90%, respectively). It similarly showed greatly increased affinities for the serotonin 5-HT2B and 5-HT2C receptors compared to LSD.
Pharmacokinetics TRALA-12 shows dramatically faster metabolism than LSD in human liver microsomes in vitro. Whereas about 75% remained in the case of LSD following incubation after 4hours, only about 10% of TRALA-12 remained with incubation after 1hour. It was concluded that due to its very fast metabolism, TRALA-12 is likely not orally active, but may be active via intravenous infusion with short-lasting effects that can be rapidly terminated upon cessation of infusion.
Chemistry Synthesis The chemical synthesis of TRALA-12 has been described.
History TRALA-12 was patented by Daniel Trachsel and Matthias Liechti and colleagues in association with MindMed (Mind Medicine; now Definium Therapeutics) in 2023.
Research An LSD analogue called didehydro-LSD (DDH-LSD), which has a name that is structurally compatible with TRALA-12, is being developed by Matthias Liechti and colleagues as a potential novel psychedelic drug for medical applications. It is described as having similar receptor activity as LSD in vitro but as having faster in-vitro metabolism and hence as potentially having a shorter duration in comparison, similarly to the case of TRALA-12. A pharmacokinetic clinical study of DDH-LSD comparing it with LSD is underway at University Hospital Basel in Basel, Switzerland as of March 2026, with both drugs given orally (following an initial dose-finding substudy in the case of DDH-LSD).
See also Substituted lysergamide List of investigational hallucinogens and entactogens LEK-8842 (TRALA-01)
References
External links TRALA-12 - Isomer Design