RecruitingPhase 2Drug trialA Study of Alisertib in Patients With Extensive Stage Small Cell Lung CancerPUMA-ALI-4201 is a Phase 2 study evaluating alisertib monotherapy in patients with pathologically-confirmed small cell lung cancer (SCLC) following progression on or after treatment with one platinum-based chemotherapy and anti-PD-L1/PD-1 immunotherapy agent. Up to one additional systemic anti-cancer therapy for SCLC is allowed, for a total of up to two prior treatment regimens. This study is intended to identify the biomarker-defined subgroup(s) that may benefit most from alisertib treatment and to evaluate the efficacy, safety, and pharmacokinetics of alisertib.