SAGE Therapeutics, Inc. is a clinical-stage biopharmaceutical company. The Company is engaged in developing and commercializing medicines to treat central nervous system (CNS) disorders. The Company's lead product candidate, SAGE-547 is an intravenous formulation of allopregnanolone, a neurosteroid that acts as a synaptic and extrasynaptic modulator of the Gamma-Amino Butyric Acid-A (GABAA) receptor. The Company's next-generation product candidates, SAGE-217 and SAGE-689, also target the GABAA receptor system. The Company is focused on developing drugs based on selective allosteric modulation of CNS synaptic and extrasynaptic receptors. The Company's chemistry platform is focused on the chemical scaffolds of endogenous or chemically modified synthetic neuroactive steroid compounds that are allosteric modulators of GABAA or N-Methyl-D-aspartic acid or N-Methyl-D-aspartate (NMDA) receptors.