Study to Evaluate VT3989 in Patients With Metastatic Solid Tumors

Dose escalation (Part 1) will employ a traditional 3 + 3 design to assess safety of VT3989 in patients with metastatic solid tumors or mesothelioma. The 3 + 3 design will be implemented until the MTD or recommended phase 2 dose(s) and schedule(s) are determined. The MTD is defined as the highest dose level at which \< 33% of patients experience a dose limiting toxicity (DLT) during the first cycle of the study (Cycle 1). Dose Expansion (Part 2) will further evaluate the safety and assess preliminary antitumor activity at the recommended phase 2 dose(s) and schedule(s) with up to 6 cohorts. Expansion cohorts 1 and 2 will enroll patients with mesothelioma of any site origin with or without NF2 mutations. Expansion cohort 3 will enroll non-pleural mesothelioma patients. Expansion cohort 4 will enroll solid tumor patients with clearly inactivating NF2 mutations/alterations or YAP/TAZ gene rearrangements. Cohort 5 will enroll pleural mesothelioma patients. Combination part (Part 3) includes two cohorts. Cohort A will enroll mesothelioma patients who will receive VT3989 in combination with immunotherapy (nivolumab plus ipilimumab). Cohort B will enroll NSCLC patients whose tumors have exon 19 deletion or exon 21 L858R mutation and will receive VT3989 in combination with targeted therapy (Osimertinib).