Safety and Efficacy Study of Pertuzumab to Treat Castration-Resistant Prostate Cancer

Inclusion Criteria: * Signed informed consent * Age \>= 18 years old * Histologically documented adenocarcinoma of the prostate, clinically refractory or resistant to hormone therapy, as assessed by progression following at least one hormonal therapy (orchiectomy or luteinizing hormone-releasing hormone \[LHRH\] agonist). Subjects must have documented progression following hormonal therapy withdrawal of \>= 4 weeks duration; nilutamide and bicalutamide require 6 weeks withdrawal. * Progression of disease after one prior chemotherapy regimen (which must have been taxane-based) for CRPC. Progression is defined as at least one of the following: A minimum of three consecutive serum PSA measurements obtained \>= 14 days apart and all within 3 months, with progressively increasing values for two consecutive measurements. The latest value must be obtained within the screening period and must be \>= 5 ng/mL; or progression of measurable disease, as defined by RECIST; or progression of bone disease, as defined by the appearance of one or more new bone lesions * Orchiectomy, or castrate levels of testosterone maintained by LHRH agonist \<70 ng/mL * Life expectancy \>= 12 weeks * ECOG performance status of 0 or 1 * Granulocyte count of \>= 1500/mL, platelet count of \>= 75,000/mL and hemoglobin of \>= 9 g/dL (hemoglobin may be supported by transfusion or erythropoietin or other approved hematopoietic growth factors; darbopoeitin \[Aranesp\] is permitted) * Serum bilirubin less than or equal to the upper limit of normal (ULN), unless due to Gilbert's disease, and alkaline phosphatase, AST, and ALT \<= 2.5 x ULN (ALT, AST, and alkaline phosphatase \<= 5 x ULN for subjects with liver metastases; no alkaline phosphatase upper limit for subjects with bone metastases) * Serum creatinine \<= 1.5 x ULN * International normalized ratio (INR) \<1.5 and activated partial thromboplastin time (aPTT) \<1.5 x ULN (except for subjects receiving warfarin) * Willing to complete serial PROSQOLI/PPI evaluations and serial diaries of analgesic use (if necessary) Exclusion Criteria: * Prior chemotherapy, radiotherapy, therapeutic radionucleotide or immunotherapy within 4 weeks of Day 1 (the day of the first rhuMAb 2C4 dose). Flutamide therapy, or other second line hormonal therapies should be withdrawn \>= 4 weeks prior to Day 1. Bicalutamide and nilutamide therapy should be withdrawn \>= 6 weeks prior to starting study medication. * Prior treatment with HER2 pathway inhibitors (e.g., Herceptin \[Trastuzumab\], Iressa \[gefitinib\], Tarceva \[erlotinib hydrochloride\], C225, CI1033, and TAK165) * Treatment with other experimental anticancer agents within 4 weeks prior to Day 1 * Prior history or clinical evidence of central nervous system or brain metastases * Ejection fraction, determined by ECHO, \<50% * Uncontrolled hypercalcemia (\>11.5 mg/dL) * Prior exposure of \>360 mg/m2 doxorubicin, \>120 mg/m2 mitoxantrone, or \>90 mg/m2 idarubicin * Ongoing corticosteroid treatment, except for subjects who are on stable doses of \<20 mg of prednisone daily (or equivalent), or who are taking corticosteroids for reasons unrelated to prostate cancer * History of other malignancies within 5 years prior to Day 1, except for adequately treated basal or squamous cell skin cancer * History of serious systemic disease, including active infection, uncontrolled hypertension (diastolic blood pressure \>100 mmHg on two consecutive occasions), unstable angina, congestive heart failure, or myocardial infarction within 6 months prior to Day 1, or unstable symptomatic arrhythmia requiring medication (subjects with chronic atrial arrhythmia, i.e., atrial fibrillation, paroxysmal supraventricular tachycardia, or controlled hypertension are eligible) * Ongoing liver disease, including viral or other hepatitis, current alcohol abuse, or cirrhosis * Known human immunodeficiency virus infection * Major surgery or significant traumatic injury within 3 weeks prior to Day 1 * Inability to comply with study and follow-up procedures * Any other diseases, metabolic dysfunction, physical examination finding, or clinical laboratory finding giving reasonable suspicion of a disease or condition that contraindicates the use of an investigational drug or that may affect the interpretation of the results or render the subject at high risk for treatment complications