【.】評論
Pembrolizumab demonstrated superior efficacy to first-line platinum-based chemotherapy in patients with tumors expressing PD-L1 in greater than 50% of tumor cells, as assessed with immunohistochemistry. A similarly designed study did not show efficacy when nivolumab was compared to chemotherapy; however, in this study patients with tumors expressing PD-L1 in greater than 1% of tumor cells were enrolled. Pembrolizumab is approved as first-line therapy in patients with tumors that are positive for PD-L1 expression in ≥50% of tumor cells.