A Clinical Trial of Gocatamig (MK-6070) With Durvalumab in Participants With Small Cell Lung Cancer (MK-6070-004)

Researchers are looking for new ways to treat limited-stage small cell lung cancer (LS-SCLC). LS-SCLC is a type of lung cancer that has not spread from the lung to other parts of the body. Researchers want to learn if gocatamig given with durvalumab can treat LS-SCLC. The main goal of this trial is to learn if participants who receive gocatamig with durvalumab live longer without the cancer getting worse than those who receive durvalumab alone.

Inclusion Criteria: The main inclusion criteria include but are not limited to the following: * Has histologically or cytologically confirmed limited-stage small cell lung cancer (LS-SCLC) defined as Stage I-III by American Joint Committee on Cancer 9th Edition Cancer Staging * Has received appropriate definitive concurrent chemoradiotherapy (CRT; 4 cycles of platinum-based chemotherapy concurrent with radiotherapy) per protocol * Has achieved complete response, partial response, or stable disease and did not progress per protocol following definitive, platinum-based chemotherapy concurrent with radiotherapy * Is not expected to require tumor resection during the study * Is able to submit a biopsy of a tumor lesion not previously irradiated * Has well-controlled human immunodeficiency virus (HIV) on antiretroviral therapy (ART), if diagnosed with HIV * Has undetectable hepatitis B virus (HBV) viral load and has received HBV antiviral therapy, if hepatitis B surface antigen-positive * Has undetectable hepatitis C virus (HCV) viral load, if has a history of HCV infection Exclusion Criteria: The main exclusion criteria include but are not limited to the following: * Has received sequential CRT for LS-SCLC (no overlap of radiotherapy with chemotherapy) * Has clinical or radiographic progression or deterioration while on concurrent CRT * Has pleural effusion, pericardial effusion, or ascites requiring recurrent drainage procedures * Has active or history of immune deficiency (with the exception of well-controlled HIV on ART) * Has history of Kaposi's sarcoma and/or Multicentric Castleman's Disease, if diagnosed with HIV * Is expected to require any other form of antineoplastic therapy while on study * Has known additional malignancy that is progressing or required active treatment within the past 3 years * Has known central nervous system metastases or leptomeningeal disease * Has active autoimmune disease that required systemic treatment in the past 2 years * Has active infection requiring systemic therapy (other than therapies permitted per protocol) * Has active or history of neurologic paraneoplastic syndrome * Has current pneumonitis/interstitial lung disease (ILD) or history of noninfectious pneumonitis/ILD that required steroids * Has uncontrolled or significant cardiovascular disease * Has clinically severe pulmonary compromise from intercurrent pulmonary illnesses * Has history of clinically significant intracranial or spinal cord bleeding * Has history of allogeneic tissue/solid organ transplant * Has not adequately recovered from major surgery or has ongoing surgical complications