Programed cell death-1/programed death ligand-1 (PD-1/PD-L1) blockade represents an affirmed reality in the treatment of advanced non-small-cell lung cancer (NSCLC) patients. Atezolizumab, an anti-PD-L1 agent, figures among the drugs that provide previously unenvisaged outcomes in the pretreated setting of metastatic NSCLC. Increasing evidence vouches for the early administration of PD-1/PD-L1 blockers in untreated patients, encompassing atezolizumab combinations with chemotherapy and the anti-angiogenic agent bevacizumab. Moreover, the development of atezolizumab allowed to derive several hints regarding clinical and immunological factors predictive of its activity and efficacy, some of them exclusive among this class of drugs. This review provides an overview of atezolizumab development throughout clinical trials toward its applicability in the routine practice, with a particular focus on patient selection based on clinical and immune-related factors.
Keywords: ICB; NSCLC; PD-1; PD-L1; atezolizumab development; biomarkers; immune checkpoint blockers; non-small cell lung cancer.