MRG003 Induction and Capecitabine Maintenance With PD-1 in Locally Recurrent NPC

Inclusion Criteria: \*\*Inclusion Criteria:\*\* 1. Patients with locally recurrent nasopharyngeal carcinoma (NPC) more than 1 year after initial radical treatment for non-metastatic NPC, with or without regional recurrence, but without distant metastasis. 2. Age 18-70 years. 3. Pathologically confirmed local recurrence of NPC, staged as rT1-rT4 according to the 9th edition of the AJCC/UICC classification. 4. ECOG performance status score of 0-1. 5. No prior radiotherapy, chemotherapy, immunotherapy, or biological therapy for recurrent NPC. 6. No contraindications to immunotherapy or chemotherapy. 7. Adequate organ function. Exclusion Criteria: \*\*Exclusion Criteria:\*\* 1. Previous treatment with other PD-1 antibodies or immunotherapy targeting PD-1/PD-L1 resulting in Grade III or higher immune-related adverse reactions. 2. Residual toxic effects from prior anti-tumor treatments (including immunotherapy, targeted therapy, chemotherapy, or radiotherapy) (excluding alopecia, fatigue, and Grade 2 hypothyroidism) or clinically significant laboratory abnormalities higher than Grade 1 (CTCAE v5.0). 3. Congenital or acquired immunodeficiency (e.g., HIV infection), active hepatitis B (HBV-DNA ≥10 copies/ml), or hepatitis C (positive hepatitis C antibody and HCV-RNA above the detection limit of the assay). 4. Known allergy to MRG003, capecitabine, or any component of anti-PD-1 antibodies.