This is a phase I study to evaluate the safety and preliminary efficacy of \[225Ac\]Ac-DOTATATE injection combined with tislelizumab in the maintenance treatment period for patients of extensive-stage small cell lung cancer (ES-SCLC) with somatostatin receptors (SSTR)+ as first-line treatment.Patients with ES-SCLC who have completed the induction therapy of first-line standard treatment and are yet to enter the maintenance treatment period are planned to be enrolled.
Patients must have the ability to understand and sign an approved informed consent form (ICF).
Patients must be >= 18 and <＝80 years of age.
Extensive-stage small cell lung cancer that requires histopathological or cytological confirmation.
Presence of at least 1 measurable site of disease (based on RECIST 1.1).
Pregnant or lactating females.
Received systemic antitumor therapy such as targeted therapy, immunotherapy, antitumor herbal therapy, chemotherapy within 4 weeks prior to initiation of study treatment.
Uncontrolled congestive heart failure.
uncontrolled diabetes mellitus, including baseline fasting glucose > 2 x ULN.