Pembrolizumab in Subjects With Incurable Platinum-Refractory Germ Cell Tumors

OUTLINE: This is a multi-center study. Eligible subjects must have received initial cisplatin-based combination therapy, such as bleomycin-etoposide-cisplatin (BEP), cisplatin-etoposide (EP), etoposide-ifosfamide-cisplatin (VIP), or similar regimens AND demonstrated progression following the administration of at least one 'salvage' regimen for advanced germ cell neoplasm, such as high dose chemotherapy, paclitaxel-ifosfamide-cisplatin (TIP), or vinblastine-ifosfamide-cisplatin (VeIP). INVESTIGATIONAL TREATMENT: Pembrolizumab 200mg IV every 3 weeks until progression or toxicity. Treatment will continue for up to 52 weeks in the absence of prohibitive toxicities or disease progression. The following screening labs to demonstrate adequate organ function must be performed within 10 days of treatment initiation: Hematological: * Absolute neutrophil count (ANC) ≥1,500 /mcL * Platelets ≥100,000 / mcL * Hemoglobin ≥9 g/dL or ≥5.6 mmol/L without transfusion or hematopoietin (EPO) dependency (within 7 days of assessment) Renal: * Serum creatinine ≤1.5 X upper limit of normal (ULN) OR * Measured or calculated creatinine clearance ≥60 mL/min for subject with creatinine levels \>1.5 X institutional ULN * Glomerular filtration rate (GFR) can also be used in place of creatinine or creatinine clearance (CrCl) Hepatic: * Serum total bilirubin ≤ 1.5 X ULN OR * Direct bilirubin ≤ ULN for subjects with total bilirubin levels \> 1.5 ULN * AST (SGOT) and ALT (SGPT) ≤ 2.5 X ULN OR ≤ 5 X ULN for subjects with liver metastases * Albumin \>2.5 mg/dL Coagulation: * International Normalized Ratio (INR) or Prothrombin Time (PT) ≤1.5 X ULN unless subject is receiving anticoagulant therapy as long as PT or PTT is within therapeutic range of intended use of anticoagulants * Activated Partial Thromboplastin Time (aPTT) ≤1.5 X ULN unless subject is receiving anticoagulant therapy as long as PT or PTT is within therapeutic range of intended use of anticoagulants