Firazorexton

Firazorexton is an experimental orexin 2 receptor agonist first described in a 2019 patent filed by Takeda Pharmaceutical Company.
Firazorexton was studied by Takeda for the treatment of narcolepsy. It is a small-molecule and orally active compound and acts as a highly selective agonist of the orexin receptor 2 with >700-fold selectivity over the orexin receptor 1. Firazorexton is related to danavorexton.
The compound reached phase 2 clinical trials for narcolepsy. However, clinical development was discontinued in October 2021 for safety reasons. More specifically, it produced severe drug-induced liver injury in phase 2 trials. This hepatotoxicity is unlikely to be related to firazorexton's orexin receptor agonism.