Phase 2 Trial of Neoadjuvant and Adjuvant Tiragolumab Plus Atezolizumab in Patients With Newly Diagnosed PD-L1 CPS Positive Resectable Stage 3-4 Oral Cavity Squamous Cell Carcinoma (OCSCC).

Primary Objectives: To determine the major pathological response rate, defined as \<10% viable tumor in the resection specimen, after two cycles of neoadjuvant atezolizumab and tiragolumab in patients with newly diagnosed, local-regionally advanced OCSCC that is PD-L1 CPS ≥1. Response at the primary site and in nodal disease will be evaluated. Secondary Objectives: To evaluate the safety of two cycles of atezolizumab and tiragolumab in patients with newly diagnosed, local-regionally advanced OCSCC, as measured by the incidence, nature and severity of adverse events with severity measured by…