Hormone Therapy and Ipilimumab in Treating Patients With Advanced Prostate Cancer

OBJECTIVES: I. To generally test whether the addition of CTLA-4 blockade can enhance clinical treatment response in advance prostate cancer patients compared with treatment with AA therapy alone. II. To specifically examine whether concomitant AA therapy + MDX-010 can be used to prolong the progression-free interval in advanced prostate cancer patients compared with inductive short-term AA therapy alone. III. To specifically examine whether concomitant AA therapy + MDX-010 can be used to enhance initial PSA responses in advanced prostate cancer patients compared with inductive short-term AA therapy alone. IV. To specifically examine whether delayed MDX-010 can be used to induce PSA response in patients experiencing disease progression following cessation of short-term AA therapy. V. To generally examine whether MDX-010 enhances host immune response that might be involved in conferring treatment advantages to patients receiving AA therapy. VI. To specifically examine whether MDX-010 potentiates T-cell responses in advanced prostate cancer patients initiating inductive short-term AA therapy. VII. To further examine whether treatment induced T-cell responses correlate with clinical response to treatment. VIII. To examine whether short-term AA there (+/- MDX-010) induces the appearance of newly emigrated T or immature and/or B cells. OUTLINE: Patients are randomized to 1 of 2 treatment arms. ARM I: Patients receive either leuprolide acetate intramuscularly (IM) or goserelin subcutaneously (SC) on days 0, 28, and 56. Patients also receive oral flutamide three times daily or oral bicalutamide once daily. Treatment with antiandrogen (AA) therapy continues for 3 months (3-4 months for patients who initiated AA therapy \<= 21 days prior to enrollment) in the absence of disease progression or unacceptable toxicity. Patients receive ipilimumab IV over 90 minutes on day 7 (within 7-28 days post-initiation of AA therapy for patients who initiated AA therapy \<= 21 days prior to enrollment) of AA therapy. Arm II: Patients receive AA therapy as in arm I. Patients may crossover to arm II in the case of disease progression. After completion of study treatment, patients are followed periodically.