A Clinical Study of Gocatamig (MK-6070) and Infinatamab Deruxtecan (MK-2400) in People With Small Cell Lung Cancer (MK-6070-003)

Researchers are looking for new ways to treat extensive-stage small cell lung cancer (ES-SCLC). ES-SCLC is a type of lung cancer that has spread throughout the lung, to the other lung, or to other parts of the body. A standard (usual) treatment for ES-SCLC uses both chemotherapy and immunotherapy. * Chemotherapy is a treatment that works to destroy cancer cells or stop them from growing. * Immunotherapy is a treatment that helps the immune system fight cancer. Gocatamig and I-DXd (short for ifinatamab deruxtecan) are study medicines. Researchers want to know if giving gocatamig and I-DXd together can treat ES-SCLC. Researchers will also look at giving the study medicines with standard treatment. Gocatamig is a T-cell engager therapy. I-DXd is an antibody drug conjugate. * T-cell engager therapy is a certain type of immunotherapy that uses T-cells to find and destroy cancer cells. * A T-cell is a type of white blood cell, which are cells that help the body fight infection. * An antibody drug conjugate (ADC) is a treatment that attaches to a protein on cancer cells and delivers treatment to destroy those cells. The goals of this study are to learn: * About the safety of combining gocatamig and I-DXd and if people tolerate them together * If people who receive gocatamig and I-DXd have ES-SCLC respond, which means the cancer gets smaller or goes away