Immunotherapy is an important new treatment modality for NSCLC. Dual blockade of the non-redundant PD-1/PD-L1 and CTLA-4 pathways may provide additive or synergistic effects. Durvalumab is a selective, high-affinity, engineered human IgG1 mAb that blocks PD-L1 binding to PD-1 and CD80. Tremelimumab is a selective human IgG2 mAb against CTLA-4. A combination regimen of immunotherapy with chemotherapy may further enhance clinical benefit. In a Phase 1b study (NCT02537418), durvalumab ± tremelimumab combined with chemotherapy demonstrated manageable tolerability and preliminary signs of clinical activity in patients with solid tumors, including NSCLC.