A Study to Evaluate Safety, Tolerability, Pharmacokinetics, Pharmacodynamics, and Preliminary Anti-tumor Activity of RO7616789 in Advanced Small Cell Lung Cancer and Other Neuroendocrine Carcinomas

The purpose of this study is to evaluate the safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD) and preliminary anti-tumor activity of RO7616789. The study will have 3 parts: Dose Escalation (Parts 1 and 2) and Dose Expansion (Part 3). Participants with advanced stage small cell lung cancer (SCLC) and neuroendocrine carcinoma (NEC) will be enrolled in the study.

Inclusion Criteria:Life expectancy at least 12 weeksEastern Cooperative Oncology Group (ECOG) performance status of 0 or 1Adequate hematologic and end organ functionNegative serum pregnancy test.Adequate contraception and no or interruption of breastfeedingHistologically confirmed extensive SCLC or high grade NEC of any other origin, relapsed after at least 1 systemic therapyMeasurable disease according to Response Evaluation criteria in Solid Tumors (RECIST) Version 1.1Confirmed availability of representative archival tumor specimens in formalin-fixed, paraffin-embedded (FFPE) blocks or unstained slidesExclusion Criteria:Pregnant or breastfeeding, or intending to become pregnant during the study or within 40 days after the final dose of study treatmentPoorly controlled Type 2 diabetes mellitus defined as a screening hemoglobin A1c ≥ 8% or a fasting plasma glucose ≥ 160 mg/dL (or 8.8 mmol/L)QT interval corrected using Fridericia's formula (QTcF) > 470 ms demonstrated by at least two electrocardiogram (ECGs) 30 minutes apartCurrent treatment with medications that are well known to prolong the QT intervalPrior treatment with anti-cluster of differentiation (CD)137 agents, anti-CD3 agents and/or delta-like ligand 3 (DLL3) targeted therapiesAny anti-cancer therapy, whether investigational or approved, including chemotherapy, hormonal therapy, or radiotherapy, within 21 days prior to initiation of study treatmentAny history of an immune-related Grade 4 adverse event (AE) attributed to prior anti-programmed death ligand-1 (PD-L1) /PD-1 or anti-cytotoxic T-lymphocyte-associated protein (CTLA-4) therapy (other than asymptomatic elevation of serum amylase or lipase)Any history of an immune-related Grade 3 adverse event attributed to prior anti-PD-L1 /PD-1 or anti-CTLA-4 therapy (other than asymptomatic elevation of serum amylase or lipase) that resulted in permanent discontinuation of the prior immunotherapeutic agentHistory or clinical evidence of primary central nervous system (CNS) malignancy, symptomatic CNS metastases, CNS metastases requiring any anti-tumor treatment, or leptomeningeal disease and current or history of CNS disease, such as stroke, epilepsy, CNS vasculitis, or neurodegenerative diseaseSpinal cord compression that has not been definitively treated with surgery and/or radiationActive or history of clinically significant autoimmune diseasePositive test for human immunodeficiency virus (HIV) infectionPositive hepatitis B surface antigen (HbsAg) test, and/or positive total hepatitis B core antibody (HbcAb) test at screeningPrior allogeneic hematopoietic stem cell transplantation or prior solid organ transplantationAdministration of a live, attenuated vaccine within 4 weeks before first RO7616789 infusionKnown allergy or hypersensitivity to any component of the RO7616789 formulation