A Study to Evaluate Safety, Pharmacokinetics, & Activity of RO7496353 in Combination With a Checkpoint Inhibitor With or Without Standard-of-care Chemotherapy in Participants With Locally Advanced or Metastatic Solid Tumors; Urothelial Carcinoma Substudy in Association With RO7496353 Study GO44010

The purpose of this study is to evaluate the safety and tolerability of RO7496353 in combination with a checkpoint inhibitor (CPI) with or without standard-of-care (SOC) chemotherapy in participants with locally advanced or metastatic solid tumors such as non-small cell lung cancer (NSCLC), gastric cancer (GC) and pancreatic ductal adenocarcinoma (PDAC). The substudy will evaluate the safety, tolerability, pharmacokinetics, immunogenicity, and preliminary anti-tumor activity of RO7496353 in combination with atezolizumab in patients with locally advanced or metastatic urothelial carcinoma (UC). The parent and substudy will be conducted in 2 stages: an initial safety run-in stage and an expansion stage.