Naptumomab Estafenatox in Combination With Durvalumab in Subjects With Selected Advanced or Metastatic Solid Tumor, Including a Cohort Expansion in Esophageal Cancer.

Subjects must meet all of the following criteria to participate in this study: 1. Adult at least 18 years of age 2. For the Dose-escalation and MTD Expansion Cohorts: Histologically and/or cytologically confirmed solid tumor from the following list, that is metastatic/advanced, and for which no curative therapy exists: 1. Pancreatic adenocarcinoma 2. High-grade serous ovarian cancer 3. Cervical squamous cell carcinoma 4. Prostate cancer 5. ER+/HER2- or triple-negative breast cancer 6. NSCLC including driver mutation positive. 7. Mesothelioma 8. Renal cell carcinoma 9. Bladder/urothelial cancer 10. Head and neck squamous cell carcinoma 11. Melanoma 12. Hepatocellular carcinoma 13. Endometrial cancer 14. MTD Expansion Cohort only: 5T4-positive colorectal cancer and 5T4 positive GE cancer 3. For the Esophageal Expansion Cohort: Subjects must have histologically confirmed locally advanced or metastatic ESCC or AC of the esophagus or GEJ (Siewert type 1). 4. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1. 5. All patients must provide signed informed consent prior to any study specific procedures that are not part of standard medical care. 6. In the MTD Expansion Cohort only, an archival or fresh biopsy will be acceptable at baseline. A second biopsy on Cycle 2 Day 4 is optional for patients who provided a fresh biopsy at baseline or have a tumor sample available from up to 3 months prior to study entry. Patients e…