(001) Exploratory Analysis of Patient Characteristics and Treatment Duration in Patients using Esketamine for Treatment-Resistant Depression: A Large Longitudinal Study Linking Commercial Claims Data to Electronic Medical Records

Publication Number: 665

Background: Patients with major depressive disorder (MDD) may not respond to initial antidepressant therapy and develop treatment-resistant depression (TRD). Esketamine, the first prescription nasal spray for TRD, was approved by the FDA in 2019. However, little is known about the use of esketamine in the real-world clinical setting.

Objectives: To describe the real world use of esketamine and other TRD therapies including patient characteristics and treatment duration.

Methods: We conducted a retrospective longitudinal study in the IBM MarketScan Explorys Claims-Electronic Medical Record linked Database (2016-2021). TRD was identified if patients with MDD failed their first- and second-line treatments and received third-line therapy. Treatment for TRD was defined as the medications used for third-line therapy. Treatment failure was defined as switching to a different antidepressant, adding a different antidepressant, or initiating an augmentation therapy. Time to TRD was defined as the days between first-line and third-line index dates, and was further divided into the duration of the first-line and second-line treatment. The duration of TRD episode was measured as days between first and last recorded MDD diagnosis T-tests and chi-square tests were used to compare the baseline characteristics and treatment duration between patients using esketamine and other therapies as the treatment for TRD.

Results: A total of 4,101 TRD patients were identified; 188 (4.6%) used esketamine as part of their treatment regimen and 3,913 (95.4%) used other therapies during third-line treatment. Patients using esketamine for TRD were older compared to those using other therapies (44.0 ± 14.1 vs. 38.6 ± 14.9; p < 0.001) and were significantly more likely to have comorbidities (35.6% vs. 23.9%, p < 0.001, including diagnosed obesity 26.6% vs. 16.2%, hypertension 27.7% vs. 18.5%, and sleep disorder 25.0% vs. 17.4%). Compared to those using other therapies, patients using esketamine for TRD had a longer duration of second-line treatment (253.6 ± 163.5 vs. 191.3 ± 146.6, p < 0.001), while there was no significant difference in the duration of the first-line treatment (190.6 ± 170.1 vs. 186.0 ± 181.4, p = 0.670). There was no significant difference between the duration of TRD episode (714.0 ± 430.8 vs. 763.5 ± 471.5, p = 0.158).

Conclusions: This exploratory analysis describing the characteristics of TRD patients demonstrated that esketamine is more likely to be used in older patients and those with comorbidities. These patients had a longer time to TRD compared to those using other therapies, which is mainly because of a longer duration of second-line treatment.