This research study is a first-in-human Phase 1 study. The study tests the effects of study drug, ONC-783, in the treatment of advanced or metastatic colorectal cancer, ovarian cancer, pancreatic cancer, or breast cancer. The most important measurement for the study is to see whether ONC-783 is safe and tolerable, how it is processed in the blood/body and whether it could slow down tumor growth. ONC-783 is an investigational drug being developed as an anti-tumor treatment. ONC-783 is a bispecific antibody drug, which means it may bring immune cells (that protect the body against diseases) and...