A Phase 1/2 Study of BGB-B2033, Alone or in Combination With Tislelizumab With or Without Bevacizumab, in Participants With Advanced or Metastatic Solid Tumors

The purpose of this study is to evaluate the safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and preliminary antitumor activity of BGB-B2033 alone or in combination with tislelizumab, with or without bevacizumab, in adults with advanced or metastatic hepatocellular carcinoma (HCC), alpha-fetoprotein (AFP)-producing gastric cancer (GC), extragonadal yolk sac tumors, non-dysgerminomas, or glypican-3 (GPC3)-positive squamous non-small cell lung cancer (NSCLC). The study will also determine the recommended Phase 2 dose (RP2D) of BGB-B2033 when given alone or in combination with tislelizumab and bevacizumab. The main questions it aims to answer are: * Is BGB-B2033 safe and tolerable when given alone or in combination with tislelizumab, with or without bevacizumab? * How does the body process BGB-B2033, and what are its effects on the body? * Does BGB-B2033 show preliminary antitumor activity in participants with advanced or metastatic cancer? Researchers will evaluate different doses and treatment combinations to determine the safest and most appropriate dose of BGB-B2033 for further study. Participants will: * Receive BGB-B2033 by intravenous infusion, either alone or in combination with tislelizumab, with or without bevacizumab. * Have regular assessments to monitor safety, side effects, how their body processes and responds to BGB-B2033, and whether their cancer responds to treatment.