An exploratory study linked circulating neutrophil states to both resistance and toxicity patterns in advanced lung cancer treated with immune checkpoint inhibitors. Researchers reported that distinct immature and inflammatory neutrophil fingerprints were associated with poor response to therapy and a higher risk of immune-related adverse events. The approach focuses on neutrophil biology as a potential biomarker layer—capturing not just whether patients respond, but also the likelihood of immune-mediated complications. Because the data are described as exploratory, the main near-term value is hypothesis generation for larger validation studies that can test whether neutrophil state profiling can stratify patients before treatment. For clinical development and companion diagnostics teams, the findings highlight a biomarker direction beyond tumor genomics, aiming to translate peripheral immune-state information into practical decision support.