Esmirtazapine

Esmirtazapine (ORG-50,081) is a drug which was under development by Organon for the treatment of insomnia and vasomotor symptoms (e.g., hot flashes) associated with menopause. Esmirtazapine is the (S)-(+)-enantiomer of mirtazapine and possesses similar overall pharmacology, including inverse agonist actions at H₁ and 5-HT₂ receptors and antagonist actions at α₂-adrenergic receptors. As of March 2010, Merck terminated internal clinical development program for esmirtazapine, for hot flashes and insomnia, for strategic reasons.