Comparing Chemotherapy With/Without Toripalimab For Primary Metastatic Nasopharyngeal Carcinoma

Inclusion Criteria:

1. Sign an informed consent;

2. Age older than 18 years old and younger than 70 years old;

3. Patients with newly histologically confirmed primary metastatic nasopharyngealcarcinoma;

4. At least one metastatic site that fulfills the criteria of "Evaluable Disease" perRECIST 1.1 Criteria;

5. Anticipated overall survival more than 3 months;

6. Satisfactory performance status: ECOG (Eastern Cooperative Oncology Group) scale 0-1;

7. No primary treatment of radiation, surgery, chemotherapy, targeted therapy andimmune therapy post diagnosis of NPC;

8. Neutrophil ≥ 1.5×109 /L and PLT ≥100×109 /L and HGB ≥90 g/L;

9. With normal liver function test (ALT、AST ≤ 3×ULN, TBIL≤ 1.5×ULN, Albumin≥2.8g/dL );

10. With normal renal function test (Creatinine ≤ 1.5 ×ULN and creatinine clearance ≥60ml/min);

11. HBV DNA<500 IU/mL（or 2500 copies/mL）and HCV RNA negative ;

12. Male and no pregnant female, able to adapt birth control methods during treatment.

Exclusion Criteria:

1. Hypersensitivity to Toripalimab, Gemcitabine, Cisplatin and Capecitabine;

2. Symptomatic spinal cord compression, or high-risk to develop pathological fracturethat requires urgent surgery or radiation;

3. Necrotic disease, high-risk of massive nasal bleeding;

4. Suffered from malignant tumors, except cervical carcinoma in situ, papillary thyroidcarcinoma, or skin cancer (non- melanoma) within five years;

5. Receive vaccine or live vaccine within 30 days prior to signing the informedconsent;

6. Equivalent dose more than prednisone 10mg/d or other immunosuppressive treatmentswithin 28 days prior to signing the informed consent;

7. Severe, uncontrolled medical conditions and infections;

8. Active, known or suspected autoimmune disease; Type I Diabetes, hypothyroidism thoseonly need hormone replacement therapy; vitiligo or inactive asthma who don't needsystemic therapy can recruit;

9. History of interstitial lung disease;

10. HIV positive;

11. Hepatitis B surface antigen (HBsAg) positive and HBV-DNA ≥500IU/ml, or 2500cps/ml;Positive HCV RNA;

12. Other diseases which may influence the safety or compliance of the clinical trial,such as heart failure with symptom, unstable angina, myocardial infarction, activeinfections those need systemic therapy, mental illness, or their family and societyfactors;

13. Women of child-bearing potential who are pregnant or breastfeeding.