Zuranolone (ZRN) is a positive allosteric modulator of both synaptic and extrasynaptic gamma-aminobutyric acid type A receptors and a neuroactive steroid approved as an oral, once-daily, 14-day treatment course for adults with postpartum depression in the US and under investigation for adults with major depressive disorder (MDD). The randomised, double-blind, placebo-controlled, Phase 3 CORAL Study assessed the efficacy and safety of ZRN 50 mg vs placebo, each co-initiated with an open-label standard-of-care antidepressant (ADT). Patients who completed CORAL could roll over into open-label SHORELINE, which assessed the safety and tolerability of ZRN 50 mg and need for repeat treatment courses in adults with MDD.

To assess the safety and tolerability (primary endpoint) and need for repeat ZRN 50 mg treatment courses (secondary endpoint) in adults with MDD who previously enrolled in CORAL.

CORAL enrolled adults (18–64 years) with MDD and 17-item Hamilton Rating Scale for Depression (HAMD-17) total score ≥24. After completing the 6-week CORAL Study, patients who enrolled in SHORELINE could enter a 46-week observation period to assess the safety and need for 14-day repeat ZRN treatment course(s), with a total of ≤4 repeat treatment courses permitted. Patients were screened every 2 weeks with the 9-item Patient Health Questionnaire, and scores ≥10 prompted a HAMD-17 assessment within 1 week. Patients with HAMD-17 total score ≥20 were eligible for repeat ZRN course(s) ≥8 weeks after completing the prior ZRN treatment course.

Among the 190 patients from CORAL who rolled over into SHORELINE and received ≥1 ZRN treatment course in either study, 133 (70.0%) had received ZRN+ADT and 57 (30.0%) received placebo+ADT in CORAL. Overall, 118 rollover patients received ≥1 open-label ZRN treatment course in SHORELINE. For patients who received ≥1 ZRN treatment course in either study, 76.8% received 1 (54.2%; 103/190) or 2 (22.6%; 43/190) total ZRN treatment courses across both studies in up to 1 year in study. The most common (>5%) treatment-emergent adverse events (TEAEs) during treatment and 14 days following the last ZRN dose were somnolence (16.1% of patients), dizziness (8.5%), headache (8.5%), fatigue (7.6%), sedation (5.9%), and nausea (5.1%); study-period TEAEs (73.7%; 87/118) for the majority of patients were mild/moderate (69.5%; 82/118) in severity and occurred primarily during the treatment period (58.5%; 69/118). No signals for increased suicidal ideation/behaviour were observed.

Safety and tolerability among rollover patients were consistent with previous studies; most of the TEAEs reported by adults with MDD who received ZRN were mild/moderate in severity. Most patients who rolled over from CORAL to SHORELINE received ≤2 total treatment courses in up to 1 year in study.

G. Mattingly Grant / Research support from: Akili, Alkermes, Allergan (now AbbVie), Axsome, Boehringer, Janssen, Lundbeck, Medgenics, NLS-1 Pharma AG, Otsuka, Reckitt Benckiser, Roche, Sage, Sunovion, Supernus, Takeda, and Teva, Consultant of: Akili, Alkermes, Allergan (now AbbVie), Axsome, Ironshore, Intra-Cellular Therapies, Janssen, Lundbeck, Neos Therapeutics, Otsuka, Purdue, Rhodes, Sage, Sunovion, Takeda, and Teva, Speakers bureau of: Alkermes, Allergan (now AbbVie), Ironshore, Janssen, Lundbeck, Otsuka, Sunovion, and Takeda, S. Mathew Grant / Research support from: Biohaven Pharmaceuticals, Boehringer-Ingelheim, Janssen, Merck, Sage Therapeutics, Inc., and VistaGen Therapeutics, Consultant of: Allergan (now AbbVie), Alkermes, Almatica Pharma, Axsome Therapeutics, BioXcel Therapeutics, Boehringer-Ingelheim, Clexio Biosciences, COMPASS Pathways, Eleusis, EMA Wellness, Engrail Therapeutics, Greenwich Biosciences, Intra-Cellular Therapies, Janssen, Levo Therapeutics, Perception Neurosciences, Praxis Precision Medicines, Neumora, Neurocrine, Relmada Therapeutics, Sage Therapeutics, Inc., Seelos Therapeutics, Signant Health, and Sunovion, S. Parikh Grant / Research support from: Aifred, Assurex, Janssen, Mensante, Sage Therapeutics, Inc., and Takeda, S. Aaronson Grant / Research support from: COMPASS Pathways and Neuronetics; has served as a consultant to Genomind, Inc., Janssen, LivaNova PLC, Neuronetics; and Sage Therapeutics, Inc., Speakers bureau of: Janssen and Sunovion Pharmaceuticals, Inc., B. Baune Speakers bureau of: Angelini, AstraZeneca, Biogen, Bristol Myers Squibb, Janssen, LivaNova, Lundbeck, Novartis, Otsuka, Pfizer, Servier, Sumitomo Pharma, Wyeth, and Boehringer-Ingelheim, A. Czysz Shareolder of: Sage Therapeutics, Inc., Employee of: Sage Therapeutics, Inc., I. Nandy Shareolder of: Sage Therapeutics, Inc., Employee of: Sage Therapeutics, Inc., V. Ona Shareolder of: Sage Therapeutics, Inc., Employee of: Sage Therapeutics, Inc., C. Brown Shareolder of: Sage Therapeutics, Inc., Employee of: Sage Therapeutics, Inc., S. Kyaga Employee of: Biogen Inc., F. Forrestal Employee of: Biogen Inc., S. Levin Employee of: Biogen Inc., J. Doherty Shareolder of: Sage Therapeutics, Inc., Employee of: Sage Therapeutics, Inc., G. Mattingly: None Declared