Bomedemstat and Maintenance Immunotherapy for Treatment of Newly Diagnosed Extensive Stage Small Cell Lung Cancer

Inclusion Criteria: * Adult aged 18 years or older and willing and able to provide written informed consent * Histologically confirmed diagnosis of extensive stage small-cell lung cancer (ES-SCLC) * Note: Previously treated limited stage SCLC (LS-SCLC) patients are eligible if disease progression had occurred following completion of definitive treatment for LS-SCLC. Determination of disease progression after prior therapy for LS-SCLC is at the discretion of the investigator * Having received four cycles of platinum-etoposide concurrent with three or four cycles of immune checkpoint inhibitor as induction systemic therapy for ES-SCLC immediately prior to study enrollment (see below for definitions). Note that immune checkpoint inhibitor may have been omitted from the first cycle only * Platinum is defined as cisplatin or carboplatin. Immune checkpoint inhibitor is defined as atezolizumab, durvalumab, or other anti-PDL1 or anti-PD1 monoclonal antibody that is approved by the United States (US) Food and Drug Administration for first-line treatment of ES-SCLC in combination with platinum and etoposide at the time of treatment receipt. Immediately prior is defined as receipt of cycle 1 day 1 of platinum-etoposide +/- immune checkpoint inhibitor no more than 112 days prior to cycle 1 day 1 of study treatment, and administration of fourth cycle of platinum-etoposide and immune checkpoint inhibitor no more than 30 days prior to cycle 1 day 1 of study treatment * Eligible to re…