A Study of BL-B01D1+PD-1 Monoclonal Antibody in Patients With Extensive-stage Small Cell Lung Cancer

This study tests a combination of BL-B01D1 (a new antibody-drug conjugate that delivers chemotherapy directly to cancer cells) plus a PD-1 immunotherapy drug as a first-line treatment for extensive-stage small cell lung cancer — an aggressive form of lung cancer that has spread widely. **You may be eligible if...** - You are between 18 and 75 years old - You have newly diagnosed extensive-stage small cell lung cancer confirmed by biopsy or cell testing - You have not previously received treatment for this cancer - You have at least one measurable tumor - Your expected survival is at least 3 months - You are in good general health (ECOG score 0–1) - You have adequate blood counts and organ function **You may NOT be eligible if...** - You have previously received a topoisomerase I inhibitor-based antibody-drug conjugate (ADC) therapy - Your cancer has non-small cell components mixed in - You have active autoimmune diseases or are on long-term steroids - You have serious heart, brain, or cardiovascular disease - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.