Temozolomide and Atezolizumab for Subsequent Line for the Treatment of Metastatic or Recurrent Small Cell Lung Cancer

This study is testing a combination of temozolomide (a chemotherapy tablet) and atezolizumab (an immunotherapy drug) for people with small cell lung cancer that has spread and returned after previous treatment with chemotherapy and immunotherapy. **You may be eligible if:** - You are 18 or older with advanced or metastatic small cell lung cancer - Your cancer has progressed after platinum-based chemotherapy combined with immunotherapy - You have had no more than 3 prior lines of treatment - You have measurable cancer visible on imaging - Your blood counts, kidney, liver, and heart function are within acceptable ranges - You can swallow tablets **You may NOT be eligible if:** - You have received temozolomide before - Your cancer has spread to your brain and is causing symptoms - You have active autoimmune disease (like rheumatoid arthritis or inflammatory bowel disease) - You have active hepatitis B, hepatitis C, or HIV infection - You are pregnant or breastfeeding - You have a history of severe lung inflammation (interstitial lung disease) Talk to your doctor to see if this trial is right for you.