Vornorexant (developmental code names ORN-0829, TS-142) is an orexin receptor antagonist which is under development for the treatment of insomnia and sleep apnea syndrome. It is a dual orexin OX₁ and OX₂ receptor antagonist (DORA). The medication has a relatively short elimination half-life of 6 hours. As of June 2021, vornorexant is in phase 2 clinical trials for insomnia and phase 1 trials for sleep apnea syndrome.