Targeting the PD-1/PD-L1 Immune Checkpoint in EGFR-Mutated or ALK-Translocated Non-Small-Cell Lung Cancer

Immune checkpoint inhibitors, notably antibodies targeting programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1), have modified the management of patients with locally advanced or metastatic non-small-cell lung cancer (NSCLC). Several PD-1/PD-L1 inhibitors have been approved by health authorities for this indication and others are in clinical development. However, only a subset of patients truly benefits from these agents. For patients with mutated EGFR or translocated ALK NSCLC, for whom an immune checkpoint inhibitor can be prescribed after progression on tyrosine kinase inhibitors and chemotherapy, information is scarce and sometimes contradictory. Phase III randomized clinical trials have evaluated different immune checkpoint inhibitors (nivolumab, pembrolizumab, atezolizumab) vs. chemotherapy as second- or subsequent-line therapy in NSCLC, but included very few patients with EGFR/ALK-positive disease. Subgroup analyses found that these patients did not benefit from immune checkpoint inhibitors. Retrospective data show progression-free survival lasting only 1.2-2.1 months. Preclinical data suggested a lower expression of PD-L1 in EGFR/ALK-positive patients compared to EGFR/ALK-negative patients. Our objective herein is to provide an up-to-date review of available data from the various publications on the impact of immune checkpoint inhibitors in patients with EGFR/ALK-positive NSCLC.