CYT107 After Vaccine Treatment (Provenge®) in Patients With Metastatic Castration-Resistant Prostate Cancer

Inclusion Criteria: * Asymptomatic or minimally symptomatic metastatic castration-resistant prostate cancer (mCRPC) * Patients must have successfully completed therapy with sipuleucel-T within 3-7 days of planned CYT107 study drug treatment * Assessable disease with a positive bone scan and/or measurable disease on computed tomography (CT) scan and/or magnetic resonance imaging (MRI) of the abdomen and pelvis * Prior orchiectomy or must be on ongoing luteinizing hormone-releasing hormone (LHRH) agonist or antagonist (e.g., degarelix) therapy * No ongoing anti-androgen therapy; patients must be off anti-androgen therapy for at least 30 days * Patients receiving any other hormonal therapy, including any dose of megestrol acetate (Megace), Proscar (finasteride), any herbal product known to decrease prostate specific antigen (PSA) levels (e.g. saw palmetto, PC-SPES), or any systemic corticosteroid, must discontinue the agent for at least 30 days prior to study treatment * Absolute neutrophil count (ANC) \>= 1500/uL * Bilirubin \< 1.5 x upper limit of normal (ULN) * Hemoglobin \>= 10 g/dL * Platelets \>= 100,000/mcL * Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) =\< 2.5 x ULN * Creatinine clearance \>= 60 mL/min by the Cockcroft-Gault equation * Testosterone =\< 50 ng/dL (documented at any time while on LHRH agonist or antagonists or s/p orchiectomy) * Eastern Cooperative Oncology Group (ECOG) performance status of 0-1 or a Karnofsky performance status of \…