1. Nature of the Business Sage Therapeutics, Inc. (Sage or the Company) is a biopharmaceutical company committed to developing and commercializing novel medicines with the potential to transform the lives of people with debilitating disorders of the brain. The Companys lead product, ZULRESSO (brexanolone) injection, was approved by the U.S. Food and Drug Administration (FDA) in March 2019, for the treatment of postpartum depression (PPD) in adults, and was made commercially available in the U.S. beginning on June 24, 2019 after completion of controlled substance scheduling of brexanolone by the U.S. Drug Enforcement Administration and incorporation of the scheduling into the FDA-approved label and other product information. The Company has a portfolio of other product candidates with a current focus on modulating two critical CNS receptor systems, GABA and NMDA. The GABA receptor family, which is recognized as the major inhibitory neurotransmitter in the CNS, mediates downstream neurologic and bodily function via activation of GABA A receptors. The NMDA-type receptors of the glutamate receptor system are a major excitatory receptor system in the CNS. Dysfunction in these systems is implicated in a broad range of CNS disorders. The Company is targeting CNS indications where patient populations are easily identified, clinical endpoints are well-defined, and development pathways are feasible. The Company was incorporated under the laws of the State of Delaware on April 16, 2010, and commenced operations on January 19, 2011 as Sterogen Biopharma, Inc. On September 13, 2011, the Company changed its name to Sage Therapeutics, Inc. The Company is subject to risks and uncertainties common to companies in the biotech and pharmaceutical industries, including, but not limited to, the risks associated with developing product candidates at each stage of non-clinical and clinical development; the challenges associated with gaining regulatory approval of such product candidates; the risks associated with commercializing pharmaceutical products for marketing and sale; the potential for development by third parties of new technological innovations that may compete with the Companys products; the dependence on key personnel; the challenges of protecting proprietary technology; the need to comply with government regulations; the high costs of drug development; and the uncertainty of being able to secure additional capital when needed to fund operations. Under Accounting Standards Update (ASU) 2014-15, Presentation of Financial StatementsGoing Concern (Subtopic 205-40), or ASC 205-40, the Company has the responsibility to evaluate whether conditions and/or events raise substantial doubt about its ability to meet its future financial obligations as they become due within one year after the date that the financial statements are issued. The Company has incurred losses and negative cash flows from operations since its inception. As of September 30, 2019, the Company had an accumulated deficit of $1.5 billion. From its inception through September 30, 2019, the Company received net proceeds of $2.2 billion from the sales of redeemable convertible preferred stock, the issuance of convertible notes, and the sales of common stock in its initial public offering (IPO) in July 2014 and follow-on public offerings in April 2015, January 2016, September 2016, November 2017, February 2018, and February 2019. Until such time, if ever, as the Company can generate substantial product revenue and achieve profitability, the Company expects to also finance its cash needs through a combination of equity offerings, debt financings, collaborations, strategic alliances, licensing arrangements and other sources of funding. If the Company is unable to raise additional funds through equity or debt financings when needed, the Company may be required to delay, limit, reduce or terminate product development or future commercialization efforts or grant rights to develop and market products or product candidates that the Company would otherwise prefer to develop and market itself. The Company expects that, based on its current operating plans, the Companys existing cash, cash equivalents and marketable securities will be sufficient to fund its current planned operations for at least the next twelve months from the issuance of these unaudited interim condensed consolidated financial statements (condensed consolidated financial statements). At some point after that time, the Company will require additional financing to fund its future operations. Even if the Company believes it has sufficient funds for its current or future operating plans, the Company may seek additional capital if market conditions are favorable or in light of other strategic considerations.