Current and future immunotherapies for NSCLC.

Non-small cell lung cancer (NSCLC) remains the leading cause of cancer-related mortality worldwide. Immune checkpoint inhibitors targeting the PD-1/PD-L1 and CTLA-4 axes have fundamentally transformed its treatment landscape. This narrative review traces the evolution of NSCLC immunotherapy, from advanced-stage monotherapy and chemoimmunotherapy to its critical expansion into early-stage disease, highlighting the paradigm shift brought by neoadjuvant, adjuvant, and perioperative strategies. We examine essential clinical challenges, including optimal treatment duration, management of brain metastases, immune-related adverse events, and mechanisms of primary and acquired resistance, with a focus on genomic alterations like KRAS co-mutations with STK11 and KEAP1. Furthermore, we critically evaluate the evolving biomarker landscape, moving beyond PD-L1 to encompass circulating tumour DNA, microbiome composition, and multiparametric approaches like T-cell receptor clonality. Finally, we provide an in-depth exploration of next-generation strategies, including bispecific antibodies, novel checkpoint targets, mRNA vaccines, antibody-drug conjugates, and advanced cellular therapies. While significant progress has been made, refining biomarker-driven selection and optimizing combination sequencing remain paramount. This thorough synthesis highlights promising future directions to overcome these hurdles and improve long-term survival in NSCLC.