Real-World Comparison of Chemo-Immunotherapy Regimens in Metastatic NSCLC With PD-L1 <50% (ALCG-01)

Patients with metastatic non-small cell lung cancer (NSCLC) and programmed death-ligand 1 (PD-L1) expression below 50% are commonly treated with different chemo-immunotherapy regimens in routine clinical practice. Although these regimens are widely used, comparative real-world data on survival outcomes and patient-reported quality of life are limited. This prospective observational study aims to compare two commonly used treatment approaches in patients with metastatic NSCLC and PD-L1 expression \<50%: chemotherapy plus pembrolizumab versus nivolumab plus ipilimumab combined with chemotherapy. Patients will receive treatment according to routine clinical decisions made by their treating physicians; no treatment assignment or intervention will be performed as part of the study. The primary outcomes of the study are progression-free survival and overall survival. In addition, health-related quality of life will be assessed using validated patient-reported outcome questionnaires during routine follow-up. Exploratory analyses will examine treatment outcomes in relation to selected clinical and patient-related factors, such as biological age, antibiotic exposure, and dietary patterns, in subsets of patients with available data. The results of this study are expected to provide real-world evidence on survival and quality of life outcomes associated with commonly used chemo-immunotherapy strategies in metastatic NSCLC.