Bexicaserin
Bexicaserin is a selective serotonin 5-HT2C receptor agonist which is under development for the treatment of Dravet syndrome and Lennox-Gastaut syndrome. It is taken by mouth.
The drug is highly selective for the serotonin 5-HT2C receptor, with negligible affinity for the serotonin 5-HT2A and 5-HT2B receptors. Because it does not activate the serotonin 5-HT2B receptor, bexicaserin is not expected to pose a risk of cardiac valvulopathy, unlike the existing agent fenfluramine.
The activation of serotonin 5-HT2C receptors has been shown to reduce epileptic seizure activity by inhibiting T-type calcium channels. These calcium channels facilitate high frequency burst firing in principal neurons of the subiculum. This firing pattern is upregulated following status epilepticus, with these hyperactive neurons often serving as the initiation point for seizures.
As of October 2024, bexicaserin is in Phases of [clinical research#Phase III|phase 3] clinical trials for treatment of developmental disabilities. It is being developed by Longboard Pharmaceuticals.