A Study of Concurrent Chemoradiation in Combination With or Without PD1 Inhibitor AB122 Adenosine 2a Receptor / Adenosine 2b Receptor Inhibitor AB928 Therapies in Locally Advanced Head and Neck Cancers

Zimberelimab will be administered at a dose of 360 mg IV on Day 1 of each 21-day cycle for up to 11 cycles.

Etrumadenant will be administered at a dose of 150 mg by mouth once daily on days 1-21 of each 21-day cycle for up to 11 cycles.

Concurrent weekly cisplatin and radiation will be administered as part of the subject's standard of care. Cisplatin and radiation will be initiated on the same day and continue for up to 7.5 weeks.

Concurrent weekly cisplatin and radiation will be administered as part of the subject's standard of care. Cisplatin and radiation will be initiated on the same day and continue for up to 7.5 weeks.