Background: HPV-negative HNSCC is an aggressive cancer with poor prognosis, characterized by an EGFR- and TGF-β-driven fibrotic, immune-hostile tumor microenvironment (TME) that impairs therapeutic and immune penetration. Ficerafusp alfa, a first-in-class bifunctional antibody targeting EGFR and TGF-β, is designed to remodel the fibrotic TME and enable tumor penetration. In a phase 1/1b trial (NCT04429542) in patients with first-line R/M HNSCC, ficerafusp alfa plus pembrolizumab demonstrated a 54% objective response rate, a 21.7-month median duration of response, and a manageable safety profile. FORTIFI-HN01 (NCT06788990) is an ongoing randomized, double-blind, placebo-controlled, phase 2/3 trial investigating ficerafusp alfa plus pembrolizumab versus placebo plus pembrolizumab in first-line, R/M, PD-L1-positive, HPV-negative HNSCC.
Trial Design: Eligible patients have histologically confirmed R/M HNSCC with primary tumor in the oral cavity, larynx, or hypopharynx, or HPV-negative (tested centrally) oropharyngeal carcinoma, and no prior systemic therapy for R/M disease. Patients must have a PD-L1–positive tumor (CPS ≥1), measurable disease per RECIST 1.1, and ECOG performance status of 0 or 1. Patients in Phase 2 were randomized 1:1:1 to ficerafusp alfa 750mg once weekly (QW), ficerafusp alfa 1500mg QW, or placebo, each combined with pembrolizumab (200mg IV every 3 weeks; up to 35 cycles). Through integrated analysis of safety, tolerability, pharmacokinetics, pharmacodynamics, and efficacy, ficerafusp alfa 1500mg QW was selected as the optimal biological dose. Phase 3 is enrolling with 2:1 randomization to ficerafusp alfa (1500mg IV QW) or placebo (IV QW), each combined with pembrolizumab, with treatment until disease progression or unacceptable toxicity. Tumor assessments are performed every 6 weeks in the first year and every 9 weeks thereafter. Dual primary endpoints are objective response rate (blinded independent central review) per RECIST 1.1 and overall survival. Secondary endpoints include safety, additional efficacy measures, and patient-reported outcomes. The trial is actively recruiting, with a planned enrollment of ~650 patients.