Lung Cancer Clinical Trials

• At least 18 years-of-age at the time of signature of the Informed Consent Form (ICF)

• Eastern Cooperative Oncology Group (ECOG) performance status score of 0 or 1 (Appendix A)

• Histologically or cytologically confirmed pulmonary SCLC, evaluable by RECIST v1.1

• Limited-stage (LS) disease as determined by positron emission tomography (PET) scan prior to initiation of chemotherapy and radiation therapy

• Completed concurrent chemotherapy and radiotherapy for LS-SCLC without progression per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 (computed tomography \[CT\] scan chest/abdomen/pelvis; Appendix B) within 42 days before date of randomization and first dose of study treatment

‣ Chemotherapy should consist of a platinum and IV etoposide. Participants who received at least 3 cycles of chemotherapy will be eligible to participate.

⁃ Radiotherapy should be administered per institutional guidelines

• Prophylactic cranial irradiation (PCI) may be delivered at the discretion of the Investigator and institutional guidelines. PCI, if applicable, must be conducted after the end of chemoradiotherapy and completed between 14 and 42 days before date of randomization and first dose of study treatment.

• Adequate hematologic and organ function

• Willingness to abide by protocol defined contraceptive requirements for the duration of the study.