Immune checkpoint pathways in non-small cell lung cancer

Immunotherapy has evolved at a phenomenal pace in cancer therapeutics. This has primarily been fueled by the much perceived necessity to procure an alternative to current standard of care chemotherapy agents, owing to several concerns such as treatment-related toxicity and poor long-term survival associated with the same. The knowledge of various mechanisms involved in regulation of immune response to cancer cells has served a fundamental role in identifying key molecules through which immune cell activity may be modulated. This in-turn led to the development of immune-checkpoint inhibitors. Presently, lung cancer is among the most enthusiastically investigated targets for treatment with immune-checkpoint inhibitors. Encouraging results with initial trials have now translated to attempts directed at further enhancement of outcomes through various strategies. Herein, we shall present a critical assessment of data from pivotal trials that led to the Food and Drug Administration (FDA) approval of various immune-checkpoint inhibitors and also discuss novel strategies that may potentially yield outcomes superior to standard of care chemotherapy in patients diagnosed with advanced non-small cell lung cancer (NSCLC).