FORTIFI-HN01: A Study of Ficerafusp Alfa (BCA101) or Placebo in Combination With Pembrolizumab in First-Line PD-L1-pos, R or M HNSCC

Inclusion Criteria: * Age ≥18 years on the day the Informed Consent Form is signed. * Histologically or cytologically confirmed R or M HNSCC. Eligible primary tumor locations are oral cavity, hypopharynx, larynx or oropharynx (with documented HPV-negative disease if presenting with OPSCC). Note: primary tumor location of paranasal sinuses and nasopharynx, any histology are excluded. * No prior systemic therapy administered in the R or M setting; and completed systemic therapy \>6 months prior if given as part of multimodal treatment for locoregionally advanced disease in the adjuvant or definitive setting. * Archival tumor tissue or willing to undergo pretreatment biopsy at Screening if archival tissue is insufficient or unavailable. * PD-L1 CPS ≥1. * Measurable disease based on RECIST 1.1. * Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1. * Adequate organ function, as defined in the protocol. Exclusion Criteria: * Disease suitable for local therapy administered with curative intent. * Prior treatment with anti-TGFβ therapy. * Prior therapy with an anti-EGFR antibody (exception: radio sensitizing agents and multimodal treatment for locoregionally advanced disease). * Prior history of Grade ≥2 intolerance or hypersensitivity reaction to anti-EGFR therapy or other murine proteins. * Prior therapy with an immune checkpoint inhibitor completed within 6 months prior to study treatment initiation. * Progressive disease \<6 months from completion of curati…