Small Cell Lung Cancer (SCLC) Clinical Trials

• Written informed consent and Health Insurance Portability and Accountability Act (HIPAA) authorization for release of personal health information

‣ NOTE: HIPAA authorization may be included in the informed consent or obtained separately

• Age ≥ 18 years at the time of consent

• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 2

• Have a histologically or cytologically documented new diagnosis of the extensive-stage (i.e., metastatic and/or recurrent) SCLC. Patients with multiple lung nodules and/or lymph node involvement that are too extensive or have tumor/nodal volume that is too large to be encompassed in a tolerable radiation plan are allowed

‣ Recurrent limited-stage SCLC disease after 6 months of completing standard-of-care systemic platinum-based chemotherapy and radiation can be considered after discussion with the sponsor

• Measurable disease according to RECIST v 1.1

• All patients must have brain MRI. Subjects with brain metastases are eligible provided they meet the following criteria:

‣ Patients with treated brain metastases are eligible if they completed definitive therapy at least 1 week prior to the first dose of tarlatamab, are asymptomatic (unless symptoms are deemed irreversible by the investigator), and on stable dose of steroids (=\< 10 mg prednisone equivalent) for at least 7 days prior to study treatment

⁃ Patients with asymptomatic untreated brain metastases with no radiological evidence of vasogenic edema may be considered for inclusion after discussion with the sponsor

• Absolute neutrophil count (ANC) ≥ 1500 cells/uL

• Platelets ≥ 100,000/uL

• Hemoglobin ≥ 9.0 g/dL

• Lymphocyte count ≥ 500/uL

• Estimated glomerular filtration rate (eGFR) based on MDRD (Modification of Diet in Renal Disease) calculation ≥ 30 mL/min/1.73 m\^2

• Total bilirubin \< 1.5 x upper limit of normal (ULN) (or \< 2 x ULN for subjects with liver metastases, or \< 3 x ULN for subjects with known Gilbert disease)

• Aspartate aminotransferase (AST) \< 3 x ULN (or \< 5 x ULN for subjects with liver involvement)

• Alanine aminotransferase (ALT) \< 3 x ULN (or \< 5 x ULN for subjects with liver involvement)

• Alkaline phosphatase (ALP) \< 3 x ULN (or \< 5 x ULN for subjects with liver involvement)

• Albumin ≥ 2.5 g/dL

• Patients with indwelling catheters (e.g., PleurX®) are allowed

• Baseline oxygen saturation ≥ 90% on room air

• Chronic obstructive pulmonary disease (COPD) patients on stable supplementary oxygen (O2) for at least 6 months may be considered for inclusion after discussion with the sponsor

• Left ventricular ejection fraction (LVEF) ≥ 50%, no clinically significant pericardial effusion as determined by an ECHO or MUGA, and no clinically significant electrocardiogram (ECG) findings

• As determined by the enrolling physician or protocol designee, the ability of the subject to understand and comply with study procedures for the entire length of the study

• Availability of archival tissue, preferably a formalin-fixed, paraffin-embedded (FFPE) tumor tissue block (or ideally at least 15 newly cut unstained slides). For eligibility, only confirmation of archival tissue is needed. Verification of tumor burden in the biopsy is encouraged. For optimal biomarker results, tumor content should be \> 30% of total tissue area

• Be willing to provide peripheral blood samples at specified time-points during the study