A Study of SI-B001+SI-B003± Chemotherapy in the Treatment of Locally Advanced or Metastatic Non-small Cell Lung Cancer

This study is testing a combination of two experimental antibody drugs (SI-B001 and SI-B003), with or without chemotherapy, in people with locally advanced or metastatic non-small cell lung cancer (NSCLC). These drugs target proteins on cancer cells to help the immune system fight the cancer. **You may be eligible if...** - You are 18 to 75 years old with confirmed advanced or metastatic NSCLC - You have at least one measurable tumor - Your overall health and organ function meet required levels - You are willing to provide a tumor tissue sample - You have not received prior anti-cancer treatment for this advanced disease (for Phase II patients) **You may NOT be eligible if...** - You have certain known genetic mutations in your tumor (tested before enrollment) - You have active or symptomatic brain metastases - You have a history of severe interstitial lung disease - You have active autoimmune disease or have been on immunosuppressants recently - You are HIV positive or have active hepatitis B or C - You are pregnant or breastfeeding - You have had another cancer in the past 5 years (with some exceptions) Talk to your doctor to see if this trial is right for you.