Chemo-Immunotherapy Followed by Durvalumab and Ceralasertib in Treatment Naïve Patients With Extensive Stage Small Cell Lung Cancer

This study is testing a combination of chemotherapy and immunotherapy, followed by two targeted drugs (durvalumab and ceralasertib), as a treatment for extensive-stage small cell lung cancer — a fast-spreading form of lung cancer — in patients who have not yet received any treatment. **You may be eligible if...** - You are 18 or older - You have been diagnosed with extensive-stage small cell lung cancer (confirmed by biopsy) - Your general health is good (ECOG 0-1) - You are able to receive platinum-based chemotherapy - You have adequate blood, liver, and kidney function **You may NOT be eligible if...** - You have already received treatment for this stage of lung cancer - You have active autoimmune disease or are on immunosuppressants - You have had a prior organ transplant - You have uncontrolled brain metastases Talk to your doctor to see if this trial is right for you.