Exhibit 99.1

Sage Therapeutics Announces Second Quarter 2020 Financial Results and Highlights Pipeline and Business Progress

Pipeline progress continues with first patient dosed and ongoing enrollment in multiple clinical trials across the depression and neurology franchises

Durability of response was observed in patients with MDD who responded to a 2-week treatment with

zuranolone in MOUNTAIN Study six-month follow-up period

Conference call today at 8:30 a.m. ET

CAMBRIDGE, Mass. – Aug. 10, 2020 – Today, Sage Therapeutics, Inc. (NASDAQ: SAGE), a biopharmaceutical company committed to developing novel therapies with the potential to transform the lives of people with debilitating disorders of the brain, reported business highlights and financial results for the second quarter ended June 30, 2020.

During the quarter, Sage initiated enrollment and dosing in two new trials with zuranolone 50 mg:

In addition, Sage initiated dosing in the 50 mg cohort of the open-label Phase 3 SHORELINE Study and is on-track to initiate dosing in 2H 2020 in the Phase 3 CORAL Study (MDD-305) investigating zuranolone 50 mg as an acute rapid response therapy (RRT) in patients with MDD when co-initiated with a newly administered standard antidepressant therapy. The Company also initiated dosing in the Phase 2 KINETIC Study evaluating SAGE-324 in patients with essential tremor and is on-track to initiate the Phase 2 PARADIGM Study in the second half of 2020 evaluating SAGE-718 in patients with Parkinson’s disease (PD) with impaired cognitive function.

Sage also reported results from the 6-month follow-up cohort with zuranolone 30 mg from the MOUNTAIN study. There were no symptoms of withdrawal observed after discontinuation of zuranolone (Day 14) and 74.5% of patients who responded to zuranolone maintained their response at the last follow-up at Day 182. Zuranolone was generally well-tolerated and showed a similar safety profile as seen in earlier studies.

“We have created a novel drug company successfully able to convert our chemical equity into a rich pipeline of clinical assets that are new chemical entities, not repurposed molecules,” said Jeff Jonas, M.D., chief executive officer at Sage Therapeutics. “Even in the face of the difficulties currently challenging the world, I’m pleased to report that the team at Sage is executing across all three brain health franchises and we expect to report on numerous catalysts in the next 18 months.”

Portfolio Updates

Sage is advancing a portfolio of novel, new chemical entities with the potential to become differentiated products designed to improve brain health by targeting the GABA_A and NMDA receptor systems. Dysfunction in these systems is thought to be at the core of numerous neurological and neuropsychiatric disorders.

Depression Franchise

Sage’s depression franchise features zuranolone, Sage’s next-generation positive allosteric modulator (PAM) of GABA_A receptors being evaluated in clinical development as a treatment for various affective disorders and ZULRESSO^TM (brexanolone) CIV injection, approved by the U.S. Food and Drug Administration (FDA) as the first treatment specifically indicated for PPD. Zuranolone received breakthrough therapy designation from the U.S. FDA for the treatment of MDD.

Sage is on-track to commence dosing of the third new zuranolone Phase 3 trial in 2020:

Additional study updates:

Safety:

Durability of treatment:

Neurology Franchise

SAGE-324, a next-generation PAM of GABA_A receptors and Sage’s lead neurology asset, is in development as a potential oral therapy for neurological conditions, such as essential tremor (ET), epilepsy and Parkinson’s disease.

Neuropsychiatry Franchise

SAGE-718, Sage’s first-in-class NMDA receptor PAM and lead neuropsychiatric drug candidate, is in development as a potential oral therapy for cognitive disorders associated with NMDA receptor dysfunction, potentially including Huntington’s disease (HD), Parkinson’s disease (PD) and Alzheimer’s disease (AD).

Anticipated Upcoming Milestones

2H 2020

2021

Financial Results for the Second Quarter 2020

Financial Guidance

Conference Call Information

Sage will host a conference call and webcast today, Monday, August 10, 2020, at 8:30 a.m. ET to discuss its second quarter 2020 financial results and recent corporate updates. The live webcast can be accessed on the investor page of Sage’s website at investor.sagerx.com. A replay of the webcast will be available on Sage’s website approximately two hours after the completion of the event and will be archived for up to 30 days.

About Sage Therapeutics

Sage Therapeutics is a biopharmaceutical company committed to developing novel therapies with the potential to transform the lives of people with debilitating disorders of the brain. We are pursuing new pathways with the goal of improving brain health, and our depression, neurology and neuropsychiatry franchise programs aim to change how brain disorders are thought about and treated. Our mission is to make medicines that matter so people can get better, sooner. For more information, please visit www.sagerx.com.

Forward-Looking Statements

Various statements in this release concern Sage’s future expectations, plans and prospects, including without limitation: our views and expectations regarding revenues from sales of ZULRESSO and the expected continuing impact of the COVID-19 pandemic on ZULRESSO revenues; our clinical development plans and expected timelines; our expectations with respect to 2020 operating expenses and year-end cash; our belief that existing cash will support operations into 2022; our belief in the potential of our product candidates in various indications; the potential profile and benefit of our product candidates; and the goals, opportunity and potential for our business. These statements constitute forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These forward-looking statements are neither promises nor guarantees of future performance, and are subject to a variety of risks and uncertainties, many of which are beyond our control, which could cause

actual results to differ materially from those contemplated in these forward-looking statements, including the risks that: we may never be able to generate meaningful revenues from sales of ZULRESSO or to generate revenues at levels necessary to justify our investment; the impact of the COVID-19 pandemic on sales of ZULRESSO may last longer than we expect or may reoccur in waves; our post-restructuring focus on geographies where there are existing, active ZULRESSO treating sites may not be sufficient for us to achieve success from the sale of ZULRESSO or to generate revenues at meaningful levels or at levels necessary to justify our investment even after the impact of the COVID-19 pandemic lessens; we may not be able to overcome the barriers to treatment with ZULRESSO or we may continue to encounter other issues or challenges in commercializing ZULRESSO which could further limit the potential of ZULRESSO and the timing and amount of future revenues; results achieved with use of ZULRESSO in the treatment of PPD in commercial use may be different than observed in clinical trials, and may vary among patients; the number of women with PPD or the unmet need for additional treatment options may be significantly smaller than we expect; we may encounter delays in initiation or conduct of our ongoing and planned clinical trials, including slower than expected site initiation or enrollment, that may impact our ability to meet our expected time-lines and increase our costs; we may not be able to mitigate the impact of COVID-19 on our clinical development timelines and the impact may be more significant than we expect and may negatively impact expected site initiation, enrollment or conduct in our clinical trials, or cause us to pause trials or not be able to use data, in each case which may significantly impact our ability to meet our expected time-lines or may significantly impact the integrity or sufficiency of the data from our trials or increase our costs or cause us to have to change our plans; the internal and external costs required for our ongoing and planned activities, and the resulting impact on expense and use of cash, may be higher than expected which may cause us to use cash more quickly than we expect or change or curtail some of our plans or both; our expectations as to expenses, year-end cash and cash needs may prove not to be correct for other reasons such as changes in plans or actual events being different than our assumptions; we may be opportunistic in our future financing plans even if available cash is sufficient; we may not be successful in our development of any of our product candidates in any indication we are currently pursuing or may in the future pursue; success in our non-clinical studies or in earlier clinical trials may not be repeated or observed in ongoing or future studies, and ongoing and future non-clinical and clinical results may not meet their primary or key secondary endpoints or be sufficient to file for or gain regulatory approval to market the product without further development work or may not support further development at all; we may encounter adverse events at any stage of development that negatively impact further development or that require additional nonclinical and clinical work which may not yield positive results; we may encounter different or more severe adverse events at the higher doses we are planning to study in new trials; we may encounter issues with the efficacy or durability of short-term treatment, or co-initiated treatment with zuranolone or safety and efficacy concerns with respect to retreatment that require additional studies be conducted; the FDA may ultimately decide that the design or results of our completed and planned clinical trials for any of our product candidates, even if positive, are not sufficient for regulatory approval in the indications that are the focus of our development plan; other decisions or actions of the FDA or other regulatory agencies may affect the initiation, timing, design, size, progress and cost of clinical trials and our ability to proceed with further development; we may encounter technical and other unexpected hurdles in the development and manufacture of our product candidates which may delay our timing or change our plans or increase our costs; as well as those risks more fully discussed in the section entitled “Risk Factors” in our most recent Quarterly Report on Form 10-Q, as well as discussions of potential risks, uncertainties, and other important factors in our subsequent filings with the Securities and Exchange Commission. In addition, any forward-looking statements represent our views only as of today, and should not be relied upon as representing our views as of any subsequent date. We explicitly disclaim any obligation to update any forward-looking statements.

Sage Therapeutics, Inc. and Subsidiaries

Condensed Consolidated Statements of Operations

(in thousands, except share and per share data)

(unaudited)

Sage Therapeutics, lnc. and Subsidiaries

Condensed Consolidated Balance Sheets

(in thousands)

(unaudited)

About ZULRESSO^TM (brexanolone) CIV injection

ZULRESSO, the first medicine specifically approved by the U.S. Food and Drug Administration (FDA) for the treatment of postpartum depression (PPD) in adults, is a positive allosteric modulator of both synaptic and extrasynaptic GABA_A receptors. Allosteric modulation of neurotransmitter receptor activity results in varying degrees of desired activity rather than complete activation or inhibition of the receptor.

SELECT IMPORTANT SAFETY INFORMATION

These are not all the side effects of ZULRESSO.

ZULRESSO can cause serious side effects, including:

ZULRESSO can cause other serious side effects, including:

The most common side effects of ZULRESSO include:

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Before receiving ZULRESSO, tell your healthcare provider about all your medical conditions including if you drink alcohol, have kidney problems, are pregnant or think you may be pregnant, or are breastfeeding or plan to breastfeed. It is not known if ZULRESSO will harm your unborn baby. If you become pregnant during treatment, talk with your healthcare provider about enrolling with the National Pregnancy Registry for Antidepressants at 1-844-405-6185.

While receiving ZULRESSO, avoid the following:

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. ZULRESSO and some medicines may interact with each other and cause serious side effects.

Especially tell your healthcare provider if you take other antidepressants, opioids, or Central Nervous System (CNS) depressants (such as benzodiazepines).

Please see the patient Medication Guide, including information about serious side effects, for Zulresso in the full Prescribing Information.