A Phase I, Open-Label, Multicentre Study to Evaluate the Safety, Tolerability and Pharmacokinetics of MEDI4736 in Patients With Advanced Solid Tumours

Inclusion Criteria: * In the dose-escalation phase: patients with advanced solid tumors refractory to standard treatment, intolerant of standard treatment, or for which no standard therapy exists. In the dose-expansion phase: histologically- or cytologically-confirmed advanced or metastatic biliary tract cancer (BTC), esophagus cancer(EC) (squamous cell carcinoma) or squamous cell carcinoma of the head and neck (SCCHN). - men or women. - Eastern Cooperative Oncology Group (ECOG) status of 0 or 1. - Adequate organ and marrow function. - Subjects must have at least 1 measurable lesion. - Available archived tumor tissue sample. - Willingness to provide consent for biopsy samples. Exclusion Criteria: * Any prior Grade ≥ 3 irAE while receiving immunotherapy - Prior exposure to any anti-PD-1 or anti-PD-L1 antibody - Active or prior documented autoimmune disease within the past 2 years - History of primary immunodeficiency - Symptomatic or untreated central nervous system (CNS) metastases requiring concurrent treatment - Women who are pregnant or lactating - Uncontrolled intercurrent illness - Known history of tuberculosis - Known to be human immunodeficiency virus (HIV) positive - Hepatitis B or C infection - Other invasive malignancy within 5 years