Supported by findings from the phase 3 randomized controlled trial, KEYNOTE-024 (1), this approval, in October 2016, was for pembrolizumab monotherapy in metastatic NSCLC with no EGFR or ALK genomic alterations and PD-L1 tumor proportion score (TPS) ≥50%, determined using a companion diagnostic test. Here, ALK is linked to non-small cell lung carcinoma.