BACKGROUND: The treatment landscape for advanced nonsmall cell lung cancer (NSCLC) has evolved from 2015 onward, since the introduction of immune checkpoint inhibitors (ICIs). Considering this shift, there have been limited prior analyses that assess the economic burden of NSCLC within the current treatment landscape. OBJECTIVE: To present an analysis of health care resource utilization (HCRU) and costs associated with the treatment of patients with advanced or metastatic NSCLC in the United States between 2010 and 2019. METHODS: Patients with locally advanced or metastatic NSCLC who initiated first-line (1L) systemic treatment between January 1, 2010, and June 30, 2019, were included from the HealthCore Integrated Research Database using a previously developed claims-based predictive model algorithm. Mean total HCRU and costs and mean per-person-per-year (PPPY) HCRU and costs were estimated for 2 follow-up periods: the time during the entire follow-up period and the time during the 1L treatment period. Distribution of treatment classes (defined as chemotherapy, ICIs, targeted therapies, and others) were also analyzed by index year. RESULTS: 27,257 patients met the eligibility criteria and were included in the analysis. The mean duration of follow-up for all patients was 16.6 months (median 10.6 months), and the median time to discontinuation of 1L treatment was 2.8 months. The number of outpatient visits accounted for the majority of HCRU across the entire study follow-up (mean 97.7 in total and 147.1 PPPY) and for the 1L treatment period (mean 46.3 in total and 167.5 PPPY). The total mean cost across the entire study follow-up was $158,908 ($250,942 PPPY). For the 1L treatment period, the total mean cost was $72,760 ($271,590 PPPY). Total mean outpatient costs for systemic anticancer treatment were $61,797 for the entire study follow-up ($85,609 PPPY) and $27,138 during the 1L treatment period ($92,412 PPPY). Total costs increased over the study duration, which were mainly due to increasing outpatient costs for systemic therapy. In both follow-up periods, inpatient costs, other outpatient costs (nonsystemic therapy-related costs), and pharmacy costs remained relatively stable but still accounted for more than 60% of the total costs. Analysis of treatment classes over time showed that chemotherapy was the most frequently used treatment, regardless of line of therapy. A trend was observed for increased ICI use from 2015 onward. CONCLUSIONS: Despite the improvement in treatment options, a high economic burden associated with the treatment of NSCLC still exists. The total costs have been increasing, mainly driven by outpatient costs for systemic therapy, which might reflect the greater use of ICIs for advanced NSCLC. Costs for inpatient services, other outpatient services, and pharmacy services remained stable but still accounted for the majority of the economic burden. Further studies are required to assess the impact of innovative treatments on the disease management costs of advanced NSCLC. DISCLOSURES: This study was funded by the healthcare business of Merck KGaA, Darmstadt, Germany (CrossRef Funder ID: 10.13039/100009945) as part of an alliance between the healthcare business of Merck KGaA, Darmstadt, Germany, and Pfizer. Zhang, Liu, and Yang are employees of EMD Serono. Beachler, Dinh, and Jamal-Allial are employees of HealthCore Inc., which received funding from the healthcare business of Merck KGaA, Darmstadt, Germany, and Pfizer for the implementation of this study. Masters and Kolitsopoulos are employees of Pfizer. Lamy was an employee of the healthcare business of Merck KGaA, Darmstadt, Germany, at the time this study was conducted.