Moreover, based on the risk–benefit profile depicted in the KEYNOTE-042 study, pembrolizumab monotherapy can be extended by FDA registration (but not by the European Medicines Agency registration) as first-line therapy to patients with locally advanced or metastatic NSCLC without sensitizing EGFR or ALK alterations and with low PD-L1 expression (≥1%) as determined by an FDA-approved test (19). This evidence concerns the gene CD274 and non-small cell lung carcinoma.