Bintrafusp Alfa in Previously Treated Patients With R/M Non-keratinizing NPC

Inclusion Criteria: * Histologically or cytologically confirmed non-keratinizing differentiated (World Health Organization WHO Type II) or undifferentiated (WHO Type III) nasopharyngeal carcinoma (NPC) that has recurred at regional or / and distant sites * Measurable disease according to the RECIST criteria (version 1.1) for the evaluation of measurable disease * Received one or more lines of chemotherapy, which must include prior treatment with a platinum agent either for the treatment of metastatic or recurrent disease * Experienced progression of disease within 6 months following completion of a platinum-based combination therapy as part of (neo)-adjuvant therapy * Male or female subjects with age: 18-79 years old * Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1 or 2 * No prior immunotherapy * Written informed consent obtained for clinical trial participation and providing archival tumor tissue, if available * Females of childbearing potential or non-sterilized male who are sexually active must use a highly effective method of contraception * Females of childbearing potential must have negative serum or urine pregnancy test * Have life expectancy ≥ 3 months * Adequate organ function as defined as: Absolute neutrophil count ≥ 1.5 x 10\^9/L, Platelet count ≥ 100 x 10\^9/L, Hemoglobin \>= 8.0 g/dL, Serum alanine aminotransferase (\[ALT\]; serum glutamate-pyruvate transferase \[SGPT\]), or serum aspartate aminotransferase \[AST\] where available at the center) \< 2.5 x upper limit of normal (ULN), OR \< 5 x ULN in the presence of liver metastases * Serum total bilirubin \< 2 x ULN * Serum creatinine \< 1.5 x ULN Exclusion Criteria: * Prior invasive malignancy within 2 years except for non-invasive malignancies such as cervical carcinoma in situ, in situ prostate cancer, non-melanomatous carcinoma of the skin, lobular or ductal carcinoma in situ of the breast that has been surgically cured * Isolated local recurrence or persistent disease * Has disease that is suitable for local therapy administrated with curative intent * Severe, active co-morbidity * Currently participating in and receiving clinical trial treatment or has participated in a trial of an investigational agent and received study treatment or used an investigational device within 4 weeks of the first dose of treatment * Has prior chemotherapy, targeted therapy, or radiation therapy within 2 weeks prior to study Day 1 or who has not recovered (≤ grade 1 or at baseline) from adverse events due to previous administered agent * Untreated active central nervous system (CNS) metastatic disease, lepto-meningeal disease, or cord compression * Clinically significant (active) cardiovascular disease: cerebral vascular accident/stroke (\<6 months prior to enrollment), myocardial infarction (\<6 months prior to enrollment), unstable angina, congestive heart failure (≥New York Heart Association Classification Class II), or serious cardiac arrhythmia requiring medication. * Prior treatment with any other anti-programmed cell death protein-1 (anti-PD-1), or PD Ligand-1 (PD-L1) or PD Ligand-2 (PD-L2) agent or an antibody targeting other immuno-regulatory receptors or mechanisms * Irritable bowel syndrome or other serious gastrointestinal chronic conditions associated with diarrhea within the past 3 years prior to the start of treatment * Known history of testing positive for HIV or known acquired immunodeficiency syndrome. * On chronic systemic steroid or any other forms of immunosuppressive medication within 14 days prior to the treatment. Except: Intra-nasal, inhaled, topical steroids, or local steroid injection (e.g., intraarticular injection); Systemic corticosteroids at physiologic doses ≤10 mg/day of prednisone or equivalent; Steroids as premedication for hypersensitivity reactions due to bintrafusp alfa * Active or prior documented autoimmune or inflammatory disorders in the past 2 years, except diabetes type I, vitiligo, psoriasis, or hypo- or hyperthyroid diseases not requiring immunosuppressive treatment * Known active hepatitis B or known hepatitis C is detected; subjects who have been treated and now have an undetectable viral load are eligible * History of primary immunodeficiency or solid organ transplantation * Receipt of live, attenuated vaccine within 28 days prior to the study treatment * Active infection requiring systemic therapy * Severe hypersensitivity reaction to treatment with another monoclonal antibody (mAb) * Females who are pregnant, lactating, or intend to become pregnant during their participation in the study * Psychiatric disorders and substance (drug/alcohol) abuse