A Global Study of Volrustomig (MEDI5752) for Participants With Unresected Locally Advanced Head and Neck Squamous Cell Carcinoma Following Definitive Concurrent Chemoradiotherapy

Inclusion Criteria:

• Histologically or cytologically documented locally advanced squamous cell carcinomaof the oropharynx, hypopharynx, oral cavity, or larynx with no evidence ofmetastatic disease (i.e. M0).

• Confirmed unresected Stage III, Stage IVA or IVB according to the eighth edition ofthe American Joint Committee on Cancer (AJCC) staging manual (tumor, node,metastasis (TNM) staging system).

• Participants will have completed definitive concurrent chemoradiotherapy (cCRT) withcurative intent prior to randomization.

Exclusion Criteria:

• Histologically/cytologically confirmed head and neck cancer of any other primaryanatomic location in the head and neck not specified in the inclusion criteriaincluding participants with squamous cell carcinoma of unknown primary ornon-squamous histologies (eg, nasopharynx or salivary gland). Participants with >1primary tumors are not eligible for the study.

• Participants with any of the following:

1. LA-HNSCC that was resected before definitive cCRT

2. LA-HNSCC that was treated and is recurrent at the time of screening

• Participants who have received radiotherapy (RT) alone as definitive local therapyfor LA-HNSCC.