Advances in the Development of Molecularly Targeted Agents in Non-Small-Cell Lung Cancer

Non-small-cell lung cancer (NSCLC) remains a significant global health challenge and the leading cause of cancer-related mortality. The traditional 'one-size-fits-all' treatment approach has now evolved into one that involves personalized strategies based on histological and molecular subtypes. The molecular era has revolutionized the treatment of patients harboring epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK) and ROS1 gene aberrations. In the appropriately selected population, anti-tumor agents against these molecular targets can significantly improve progression-free survival. However, the emergence of acquired resistance is inevitable. Novel potent compounds with much improved and rational selectivity profiles, such as third-generation EGFR T790M resistance mutation-specific inhibitors, have been developed and added to the NSCLC armamentarium. To date, attempts to overcome resistance bypass pathways through downstream signaling blockade has had limited success. Furthermore, the majority of patients still do not harbor known driver genetic or epigenetic alterations and/or have no new available treatment options, with chemotherapy remaining their standard of care. Several potentially actionable driver aberrations have recently been identified, with the early clinical development of multiple inhibitors against these promising targets currently in progress. The advent of immune checkpoint inhibitors has led to significant benefit for advanced NSCLC patients with durable responses observed. Further interrogation of the underlying biology of NSCLC, coupled with modern clinical trial designs, is now required to develop novel targeted therapeutics rationally matched with predictive biomarkers of response, so as to further advance NSCLC therapeutics through the next decade.