Abstract 3567: Immunotherapy combined with chemotherapy versus biomarker-guided immunotherapy: A cost-effectiveness analysis

Abstract Background. PD-L1 and TMB are established biomarkers for predicting immunotherapy efficacy. However, with the substantial reduction in the cost of domestic PD-L1 testing, the value of expensive genetic testing compared to its limited benefits has become a pertinent question. Methods. Data from 309 NSCLC receiving immunotherapy and 156 NSCLC undergoing chemotherapy in CHOICE-01 clinical trial were analyzed. Using a decision tree model, patients were categorized into All-in group receiving immunotherapy combined with chemotherapy, and two control groups guided by TMB and PD-L1, respectively. Cost-effectiveness was assessed using Incremental Cost-Effectiveness Ratio (ICER). Results. The decision tree comprised three chance nodes: All-in combinational therapy, TMB-guided, and PD-L1-guided strategies (Table 1 Table 1. Structure and parameters of the decision tree. Decision Probability, % Regimen ORR mean, % ORR Distribution Adjusted mean utility All-in 100 Comb 65.70 Beta(203, 106) R: 0.698 NR: 0.567 TMB TMB-H: 30.96 Comb 72.73 Beta(56, 21) R: 0.698 NR: 0.567 TMB-L: 69.04 Chemo 45.88 Beta(39, 46) R: 0.690 NR: 0.547 PD-L1 Pos: 65.16 Comb 68.00 Beta(136, 64) R: 0.698 NR: 0.567 Neg: 34.84 Chemo 39.62 Beta(21, 32) R: 0.690 NR: 0.547 ). The TMB-H group exhibited the highest response rate, followed by the PD-L1 positive group, both exceeding an overall response rate of 65.7%. Utility values for partial response (PR), stable disease (SD), and progressive disease (PD) were retrieved from previous studies, then adjusted by weighted average of SD and PD distribution and adverse reaction-related disutility. After model evaluation, the All-in, TMB-guided, and PD-L1 guided strategies yielded utility of 0.653, 0.638, and 0.628, respectively. Corresponding costs were ¥3, 202, ¥3, 833, and ¥11, 395. Given the decreasing utility and increasing cost across the strategies, calculating the ICER was deemed unnecessary. Conclusion. The All-in strategy demonstrated the highest utility and lowest cost, indicating it as the most cost-effective option for patients considering immunotherapy combined with chemotherapy. However, as this study focused on ORR, it only reflects short-term cost-effectiveness. Further investigation into long-term cost-effectiveness regarding survival outcomes is warranted. Citation Format: Fubing Wu, Feilong Zhao, Ding Zhang, Wen Huang. Immunotherapy combined with chemotherapy versus biomarker-guided immunotherapy: A cost-effectiveness analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 3567.