A Phase 3 Trial in Advanced Epithelioid Mesothelioma

Inclusion Criteria: * Male or female, age 18 years or older at informed consent. * Pathologically confirmed advanced epithelioid pleural mesothelioma previously treated with platinum-based systemic chemotherapy and immunotherapy, given sequentially or concurrently. * Radiologically measurable disease by modified RECIST v1.1 or RECIST v1.1. * ECOG: 0-1. * Adequate organ functions, including the liver, kidneys, and hematopoietic system. Exclusion Criteria: * Active brain metastases or primary CNS (central nervous system) tumors. * History of leptomeningeal metastases * Active or chronic, uncontrolled bacterial, viral, or fungal infection(s) requiring systemic therapy * Known HIV positive or active Hepatitis B or Hepatitis C * Clinically significant cardiovascular disease and prior exposure to cardiotoxic agents * Corrected QT (QTcF) interval \> 470 msec (using Fridericia's correction formula). * Women who are pregnant or breastfeeding * Non-pleural mesothelioma at initial diagnosis or an aggressive histologic type such as sarcomatoid or biphasic mesothelioma. * Prior treatment with a TEAD inhibitor, including VT3989 or another agent targeting the same molecular pathway. * Prior receipt of both comparator treatments, gemcitabine and vinorelbine, alone or in combination, or known hypersensitivity to both. A participant who received only one comparator may enroll but must not be assigned to that same comparator.