Neoadjuvant Presurgical Becotatug Vedotin (MRG003) Plus Pucotenlimab (HX008) in Oral Cavity Squamous Cell Carcinoma

Prior treatment

• Active pulmonary tuberculosis infection within the past 1 year, or history of active tuberculosis \>1 year ago unless documented prior standard anti-tuberculosis treatment.
• Systemic corticosteroids (\>10 mg/day prednisone equivalent) or other immunosuppressive therapy within 28 days prior to signing informed consent. Patients receiving ≤10 mg/day prednisone equivalent or inhaled/topical corticosteroids are eligible.
• Live vaccination within 30 days prior to signing informed consent or planned during the study.
• Prior surgery, chemotherapy, radiotherapy, immunotherapy, or other anti-tumor therapy for head and neck cancer (excluding diagnostic procedures).

Other illness

• History of other malignancies within the past 5 years, except adequately treated basal cell carcinoma, squamous cell carcinoma of the skin, or carcinoma in situ of the cervix.
• HIV infection.
• HBsAg positive with HBV DNA \>200 IU/mL or 1000 copies/mL.
• HCV antibody positive.
• History of interstitial lung disease.
• Active, known, or suspected autoimmune disease. Exceptions: type I diabetes, hypothyroidism requiring only hormone replacement therapy, and skin conditions not requiring systemic treatment (e.g., vitiligo, psoriasis, alopecia).
• Known hypersensitivity to macromolecular protein preparations, or any component of Becotatug vedotin, Pucotenlimab, or cisplatin.

Lab values

• Severe concurrent diseases that may pose significant risks or affect trial compliance, including unstable cardiac disease, renal disease, chronic hepatitis, poorly controlled diabetes (fasting blood glucose \>1.5×ULN), severe cognitive impairment, or psychiatric disorders.

Age

• Age \>70 years or \<18 years.

Other

• Pregnancy, lactation, or anticipated pregnancy during the study period.

• Voluntary participation with written informed consent, good compliance, and willingness to complete follow-up.
• Age ≥18 years and ≤70 years, regardless of gender.
• ECOG performance status score of 0 or 1.
• Histopathologically confirmed, previously untreated, primary oral cavity squamous cell carcinoma (OSCC); central laboratory-confirmed PD-L1 Combined Positive Score (CPS) ≥1; clinical stage III-IVA (AJCC 8th edition) with potential for curative surgical resection as assessed by the investigator; no evidence of definite locoregional residual or distant metastasis.
• Adequate organ function within 14 days prior to the first dose, without transfusion or hematopoietic growth factor support:
• Bone marrow: ANC ≥1.5×10\^9/L; platelet count ≥100×10\^9/L; hemoglobin ≥90 g/L.
• Liver: TBIL ≤1.5×ULN; AST/ALT ≤3.0×ULN; ALP ≤2.5×ULN; serum albumin ≥28 g/L.
• Kidney: creatinine clearance (Ccr) ≥40 mL/min (calculated by Cockcroft-Gault formula) or serum creatinine ≤1.5×ULN.
• Coagulation: INR ≤1.5×ULN and APTT ≤1.5×ULN (excluding patients receiving therapeutic anticoagulation).
• Cardiac: LVEF ≥50% with no significant cardiac dysfunction.
• Negative serum pregnancy test within 7 days prior to the first dose for women of childbearing potential; all fertile male and female participants must agree to use highly effective contraception from signing of informed consent through 1 year after the last dose of Pucotenlimab.