lipase elevation). Prior to resumption of the study, an expedited safety report will be sent to and reviewed by FDA. Serious adverse events (SAEs) also must be evaluated by the clinical investigators. After completed enrollment of arm A, enrollment to arm B will proceed if 1 patient in arm A experience a DLT. After completed enrollment of arm B, enrollment to arm C will proceed if 1 patient in arm B experience a DLT. If 2 patients in a given study arm experience a DLT, accrual to that arm will be halted. 29 Abbreviated Title: Neoadjuvant IO for HNSCC Version Date: August 31, 2022 3.2 DRUG A DMINISTRATION 3.2.1 General rule A window of +/-3 days for every two weeks study drug(s) dosing is allowed in the event of scheduling issues (i.e. holiday, bad weather or other scheduling issues).