Study of INBRX-105 and INBRX-105 With Pembrolizumab in Patients With Solid Tumors Including Head and Neck Cancer

Inclusion Criteria: * Parts 1 and 3 (escalation cohorts; completed): Patients with locally advanced or metastatic non-resectable solid tumors, whose disease has progressed despite standard therapy and for whom no further standard therapy exists. * Part 2 (expansion cohorts): Patients with non-small cell lung cancer, cutaneous melanoma, head and neck squamous cell carcinoma or solid tumors amenable to paired biopsies, with locally advanced or metastatic, non-resectable disease, which has progressed despite standard therapy or for whom no standard or clinically acceptable therapy exists. * Part 4 relapsed or refractory to CPI cohorts: NSCLC, cutaneous melanoma, HNSCC, MSI/TMB-high or MMRd solid tumors * Part 4 CPI naive cohorts: locally advanced or metastatic, non-resectable NSCLC or HNSCC * Refractory or relapsed to anti-PD-1 or anti-PD-L1, and anti-CTLA4 if applicable (NOTE: For all tumor types with checkpoint inhibitor approvals) with exception of the treatment naive NSCLC cohort. * PD-L1 positivity by immunohistochemistry (IHC): Parts 1 and 3 (escalation cohorts) PD-L1 positivity is not required. Parts 2 and 4 (expansion cohorts): Combined Positive Score (CPS) or Tumor Proportion Score (TPS) above certain thresholds as defined per protocol. * Adequate hematologic, coagulation, hepatic and renal function as defined per protocol. * Eastern Cooperative Oncology Group performance status (ECOG PS) of 0 or 1. Exclusion Criteria: * Prior exposure to 4-1BB agonists. * Receipt of…