Aims Major depressive disorder (MDD) is a prevalent, chronic disorder. Auvelity (dextromethorphan-bupropion) is a novel, oral N-methyl-D-aspartate (NMDA) receptor antagonist and sigma-1 receptor agonist approved (August 2022) by the FDA for treating MDD in adults. This is the first analysis on real-world Auvelity usage in the United States. Methods Adult patients initiating Auvelity in the Symphony IDV databases by September 2023 were identified (index date: the first Auvelity claim). Patients had continuous eligibility over the 12-month pre-index period and ≥1 MDD diagnosis (ICD-10-CM codes: F32.*, F33.*) over the 5-year pre-index period. Demographic and clinical characteristics, comorbidities, prior MDD-related medications, and Auvelity initiation status were assessed. Results This analysis included 22,288 patients with MDD treated with Auvelity (mean age 45.1 years; 68.1% women); 40.0% lived in the South and 58.5% had commercial insurance. Comorbidities included mental health disorders (53.5%; 47.6% had anxiety disorders). Overall, 83.7% of the patients had received treatment with selective serotonin reuptake inhibitors (SSRIs; 54.9%), the norepinephrine-dopamine reuptake inhibitor (NDRI [bupropion]; 40.4%), and/or serotonin-norepinephrine reuptake inhibitors (SNRIs; 35.9%) over the 12-month pre-index period. The last MDD-related treatment prior to Auvelity comprised SSRI (22.4%), SNRI (13.2%), and NDRI (12.8%) monotherapies; 294 (1.3%) patients received esketamine. In total, 6,418 (28.8%) patients initiated Auvelity as monotherapy vs 15,870 (71.2%) as an add-on; Auvelity was most frequently added to an SSRI alone (10.7%) or SNRI alone (6.5%). A total of 2,254 (10.1%) patients initiated Auvelity without prior treatment in the 12-month pre-index period. Limitations Incomplete data due to reporting; diagnoses captured subject to coding error; and limited generalizability to other populations. Conclusions Using a large demographically distributed claims database, 22,288 patients with MDD initiated Auvelity within a year of its approval; 10.1% were treatment-naïve and 28.8% initiated Auvelity as monotherapy. Most patients had mental health-related comorbidities and attempted various MDD-related treatments prior to Auvelity.