Sage Therapeutics is a biopharmaceutical company focused on brain health. Sage's sole commercial product is ZURZUVAE (zuranolone), the only FDA-approved oral treatment for postpartum depression (PPD) in adults. ZURZUVAE is a 14-day, once-daily oral treatment that can work in as few as 2–3 days, compared to weeks for standard antidepressants. Sage co-promotes ZURZUVAE in the U.S. with Biogen under a 50/50 profit and loss sharing arrangement; Biogen records all U.S. product sales, and Sage recognizes 50% of net revenues as collaboration revenue. Key revenue drivers include prescription volume, payor coverage, and sales force investment — Sage characterizes PPD as a "promotionally responsive" market and is actively investing in sales force expansion and direct-to-consumer advertising. Sage's pipeline includes SAGE-319, an early-stage GABAA receptor modulator in Phase 1 for neurodevelopmental disorders, and a preclinical NMDA receptor platform. Several programs were discontinued in 2024, including dalzanemdor, which failed in three Phase 2 trials, and SAGE-324 in essential tremor. Sage does not manufacture its own drugs and relies on contract manufacturers. In early 2025, Sage's board rejected an unsolicited acquisition proposal from Biogen and launched a strategic alternatives review.