Neoadjuvant Becotatug Vedotin Plus Pucotenlimab and Cisplatin for Locally Advanced Head and Neck Squamous Cell Carcinoma

Inclusion criteria

• Aged 18-70 years (inclusive).
• Histopathologically confirmed Stage III/IVA head and neck squamous cell carcinoma (HNSCC) of the oropharynx, oral cavity, hypopharynx, or larynx (per 8th edition AJCC Cancer Staging Manual).
• Measurable primary lesions per RECIST v1.1.
• Treatment-naive (no prior anti-tumor therapy for current disease).
• ECOG performance status 0-1.
• Eligible for elective standard surgery plus adjuvant chemoradiotherapy/radiotherapy (investigator-assessed).
• No active autoimmune diseases.
• No concurrent malignant tumors.
• Estimated life expectancy >= 6 months.
• Available tumor tissue for PD-L1 IHC testing (22C3 DAKO assay).
• Adequate hematological function (screening): ANC >= 1.5×10⁹/L, platelets >= 100×10⁹/L, Hb >= 100 g/L, WBC >= 3.5×10⁹/L; no blood transfusion or bleeding tendency within 7 days.
• Normal liver function: ALT, AST, ALP, serum bilirubin <= 1.5×ULN.
• Normal renal function: Serum Cr <= 1.5×ULN or creatinine clearance > 60 mL/min.
• HPV status confirmed by p16 IHC and in situ hybridization (ISH).
• Voluntary participation with signed informed consent; legal guardian-signed consent for incompetent subjects, and witness-supervised consent for illiterate subjects.

Exclusion criteria

• Cachexia or multiple organ failure.
• Active autoimmune disease of any type.
• Concomitant second primary malignancy (e.g., esophageal cancer).
• Severe active infection requiring systemic therapy.
• Uncontrolled serious medical conditions interfering with study treatment (e.g., severe heart/cerebrovascular disease, uncontrolled diabetes/hypertension, active peptic ulcer).
• Dementia, altered mental status, or other conditions impairing informed consent or questionnaire completion.
• Peripheral neuropathy >= Grade 2 per CTCAE v5.0.
• Hearing impairment >= Grade 2 per CTCAE v5.0.
• History of malignancy within 5 years prior to screening.
• Known HIV-positive status or diagnosed AIDS.
• Nasopharyngeal carcinoma or HNSCC at sites other than oral cavity, oropharynx, larynx, hypopharynx (e.g., paranasal sinuses, unknown primary).
• Receipt of investigational drugs or participation in other interventional trials within 30 days prior to screening.
• Systemic glucocorticoids (>10 mg prednisone equivalent/day) or other immunosuppressants within 14 days prior to randomization (inhaled/topical steroids and adrenal hormone replacement are permitted without active autoimmune disease).
• Pregnant/lactating women; subjects of childbearing potential refusing contraception.
• Active infection requiring treatment or systemic anti-infective use within 1 week prior to first dose.
• Live vaccine administration within 30 days prior to first dose.
• Vulnerable populations (e.g., mental illness, cognitive impairment, critically ill status).
• Other conditions deemed unsuitable for enrollment by the investigator.