OBJECTIVES: To characterize patients with treatment-resistant depression (TRD) initiating esketamine or conventional therapies.

METHODS: Adults with a Major Depressive Disorder diagnosis were selected from the MarketScan® Databases (01/2010-07/2020). A claims-based algorithm identified TRD as the initiation of a new antidepressant therapy after 2 different lines of adequate dose and duration during the most recent major depressive episode. Patients with observed evidence of TRD receiving treatment on/after 03/05/2019 (esketamine approval date) were then classified in the esketamine cohort if they initiated esketamine (index date), or conventional therapies cohort if they newly initiated electroconvulsive therapy (ECT), transcranial magnetic stimulation (TMS) or pharmacological therapies (index date was the therapy initiation date, prioritizing ECT, then TMS). Patient characteristics were described over 6-months pre-index.

RESULTS: Esketamine cohort included 246 patients (mean age 46.5 years, 63.0% female) and conventional therapies cohort included 104,164 patients (mean age 46.9 years, 74.8% female; 0.4% initiating ECT, 1.2% TMS). In esketamine and conventional therapies cohorts, 82.9% and 34.2% had a visit with psychiatrist, 77.6% and 41.4% received psychotherapy pre-index, respectively. Among those with outpatient care for MDD (esketamine: 91.9%; conventional therapies: 63.6%), 62.4% and 33.0% received it in a specialized mental-health care setting. In esketamine and conventional therapies cohorts, 34.6% and 17.6% received ≥3 unique antidepressants, 65.4% and 56.4% received antidepressant augmentation therapy. Mean monthly healthcare costs pre-index were $2,532 in esketamine and $1,873 in conventional therapies cohort, driven by outpatient costs (esketamine: $1,077; conventional therapies: $734) and pharmacy costs (esketamine: $688; conventional therapies: $468). In esketamine and conventional therapies cohorts, 58.2% and 32.4% of costs were mental-health related. Suicidal ideation or behavior was observed in 8.5% and 3.6% of esketamine and conventional therapies cohorts.

CONCLUSIONS: Among patients with TRD, those initiating esketamine relative to conventional therapies, appear more severe, use more mental-health care and medications, and have higher costs before therapy initiation.