Esketamine is Safe and Effective for Treatment-Resistant Depression in a Real-World Outpatient Setting

Abstract: Approximately one third of major depression cases will not remit even with two or more medication trials, defined as treatment-resistant depression (TRD). The newest FDA-approved treatment for TRD in adults, esketamine, has a unique mechanism with comparatively rapid clinical effect. However, its long-term clinical effects and safety in a real-world outpatient setting are unstudied. Here we present a naturalistic sample of 158 patients with TRD in a community-based outpatient setting treated with esketamine, the largest longitudinal dataset of its kind. The cohort had a mean of 5 antidepressant trials and 3 prior augmentation trials, with prior history of suicide attempt, psychiatric hospitalization, TMS, and/or ECT treatment for 80% of patients. Treatment with esketamine nasal spray (8 or more treatments of 56 or 84mg) with maintenance treatment for a subset of patients analyzed out to 100 days, resulted in remission (absolute score