Pembrolizumab plus chemotherapy versus chemotherapy alone in patients with advanced non-small cell lung cancer without tumor PD-L1 expression: A pooled analysis of 3 randomized controlled trials.

Some tumors produce a protein called programmed death ligand 1 (PD-L1), which interacts with the body's immune system and prevents an immune response against cancer. Antibody therapies such as pembrolizumab block interactions between tumor PD-L1 and the immune system and enable an immune response. Used alone, pembrolizumab provides benefit for patients with non-small cell lung cancer (NSCLC) tumors that produce PD-L1. However, when it is combined with chemotherapy, which can stimulate anticancer immune responses, pembrolizumab provides a benefit, regardless of tumor PD-L1 production. This article shows that among patients with NSCLC whose tumors produce no PD-L1, outcomes are better with pembrolizumab plus chemotherapy in comparison with chemotherapy alone.