BackgroundPatients with treatment-resistant depression (TRD) report significant deficits in physical and mental health, as well as severely impaired health-related quality of life (HRQoL) and functioning. Esketamine effectively enhances the daily functioning in these patients while also improving their depressive symptoms. This study assessed HRQoL and health status of patients with TRD, who were treated with esketamine nasal spray and an oral antidepressant (ESK + AD) vs. placebo nasal spray and an AD (AD + PBO).MethodsData from TRANSFORM-2, a phase 3, randomized, double-blind, short-term flexibly dosed study, were analyzed. Patients (aged 18–64 years) with TRD were included. The outcome assessments included the European Quality of Life Group, Five Dimension, Five Level (EQ-5D-5L), EQ-Visual Analogue Scale (EQ-VAS), and Sheehan Disability Scale (SDS). The health status index (HSI) was calculated using EQ-5D-5L scores.ResultsThe full analysis set included 223 patients (ESK + AD: 114; AD + PBO: 109; mean [SD] age: 45.7 [11.89]). At Day 28, a lower percentage of patients reported impairment in the ESK + AD vs. AD + PBO group in all five EQ-5D-5L dimensions: mobility (10.6% vs. 25.0%), self-care (13.5% vs. 32.0%), usual activities (51.9% vs. 72.0%), pain/discomfort (35.6% vs. 54.0%), and anxiety/depression (69.2% vs. 78.0%). The mean (SD) change from baseline in HSI at Day 28 was 0.310 (0.219) for ESK + AD and 0.235 (0.252) for AD + PBO, with a higher score reflecting better levels of health. The mean (SD) change from baseline in EQ-VAS score at Day 28 was greater in ESK + AD (31.1 [25.67]) vs. AD + PBO (22.1 [26.43]). The mean (SD) change in the SDS total score from baseline to Day 28 also favored ESK + AD (-13.6 [8.31]) vs. AD + PBO (-9.4 [8.43]).ConclusionsGreater improvements in HRQoL and health status were observed among patients with TRD treated with ESK + AD vs. AD + PBO.Trial registrationClinicalTrials.gov Identifier: NCT02418585.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12955-023-02113-1.