KEYNOTE-042: is lowering the PD-L1 threshold for first-line pembrolizumab monotherapy a good idea?

Prior to the advent of inhibitory antibodies targeting programmed death 1 (PD-1) or programmed death ligand 1 (PD-L1), the median overall survival (OS) for advanced/metastatic non-small cell lung cancer (NSCLC) patients receiving first-line platinum doublet chemotherapy was approximately 8–12 months and 5-year survival rates were estimated at 2% (1-3).