DSP-0390 in Combination With Atezolizumab for Small Cell Lung Cancer

Inclusion Criteria: * Histologically or cytologically confirmed small cell lung cancer. * Completed 3-4 cycles of induction chemoimmunotherapy as first line treatment of ES-SCLC without disease progression. * Measurable disease per RECIST 1.1. * At least 18 years of age. * ECOG performance status ≤ 2 * Adequate bone marrow and organ function as defined below: * Absolute neutrophil count ≥ 1.0 K/cumm * Platelets ≥ 100 K/cumm * Hemoglobin ≥ 8.0 g/dL * Total bilirubin ≤ 1.5 x IULN * AST(SGOT)/ALT(SGPT) ≤ 3.0 x IULN (≤ 5.0 x IULN for patients with liver metastases) * Calculated creatinine clearance \> 40 mL/min by Cockcroft-Gault * The effects of DSP-0390 on the developing human fetus are unknown. For this reason, people of childbearing potential and people able to father a child must agree to use adequate contraception prior to study entry, for the duration of study treatment, and for 6 months after the last dose of DSP-0390. * Ability to understand and willingness to sign an IRB approved written informed consent document. Legally authorized representatives may sign and give informed consent on behalf of study participants. Exclusion Criteria: * Prior or concurrent malignancy whose natural history has the potential to interfere with the safety or efficacy assessment of the investigational regimen. Patients with prior or concurrent malignancy that does NOT meet that definition (following discussion with the PI) are eligible for this trial * Currently receiving any…