Additional Study Information: The purpose this study to learn more about if a medication called durvalumab will work and be safe for the treatment of non-small cell lung cancer (NSCLC) that has spread to other parts of the body (metastatic) with certain genetic changes when given in combination with tremelimumab and standard chemotherapy. Additionally, this study is being done to better understand metastatic NSCLC and associated health problems. Durvalumab and tremelimumab are types of anti-cancer drugs called immunotherapy that target cancer cells by blocking the signal that prevents the immune system from seeing the cancer cell. Your immune system can then attack and kill the cancer cells. Durvalumab is approved by the Food and Drug Administration (FDA) for the treatment of patients with locally advanced NSCLC after receiving chemoradiation therapy and extensive-stage small-cell lung cancer in combination with standard chemotherapy. Durvalumab and tremelimumab in combination with chemotherapy are also approved by the FDA for the treatment of patients with metastatic NSCLC with no changes in the EGFR (epidermal growth factor receptor) or ALK (anaplastic lymphoma kinase) genes. Pembrolizumab is another anti-cancer drug which has been approved in multiple countries for treatment of patients with your condition. In this study, durvalumab plus tremelimumab are being used experimentally for this study and are not used in accordance to their labeling.