Impact of genomic HLA class I allelic imbalance on enduring immunotherapy response in advanced non–small cell lung cancer.

8582 Background: Human leukocyte antigen class I (HLA-I) molecules are essential for neoantigen presentation and T cell recognition, yet the clinical significance of allelic imbalance within HLA-I genes (HLA-AI) in immune checkpoint inhibitors (ICIs) therapy remains undefined. Methods: Here, we established haplotype-specific, coverage-based (cHLA-AI) compatible with routine biopsy-derived sequencing, based on 292 fully heterozygous non–small cell lung cancer (NSCLC) patients with paired tumor sa