Sipuleucel-T With or Without Radiation Therapy in Treating Patients With Hormone-Resistant Metastatic Prostate Cancer

PRIMARY OBJECTIVES:

I. To assess the feasibility, based on percent able or willing to receive all three infusions
of sipuleucel-T immunotherapy, when combining sipuleucel-T with radiation therapy to a single
site of metastasis delivered one week prior to beginning of sipuleucel-T therapy.

SECONDARY OBJECTIVES:

I. To assess the effect of radiation therapy to single metastasis on immune response
(antibody and T-cell proliferation to prostate acid phosphate [PAP] and fusion protein
PA2024) generated by sipuleucel-T immunotherapy.

II. To assess the effect of external beam radiotherapy to single metastasis on prostate
specific antigen (PSA) response to therapy with sipuleucel-T.

III. To assess the effect of external beam radiotherapy to single metastasis on radiographic
response rate to therapy with sipuleucel-T.

IV. To assess the time from the onset of therapy with sipuleucel-T +/- radiation to the need
for subsequent therapy for prostate cancer.

V. To assess the toxicity associated with sipuleucel-T +/- radiation.

OUTLINE: Patients are randomized to 1 of 2 treatment arms.

ARM A: Patients receive sipuleucel-T intravenously (IV) over 60 minutes days 22, 36, and 50.

ARM B: Patients undergo external beam radiation therapy in weeks 1-2. Patients also receive
sipuleucel-T as in Arm A.

In both arms, treatment continues in the absence of disease progression or unacceptable
toxicity.

After completion of study treatment, patients are followed up until week 60.

Inclusion Criteria:

- Histologically documented adenocarcinoma of the prostate

- Life expectancy of >= 6 months, Eastern Cooperative Oncology Group (ECOG) performance
status =< 2

- Metastatic disease as evidenced by soft tissue and/or bony metastases on baseline bone
scan and/or computed tomography (CT) scan or magnetic resonance imaging (MRI) of the
abdomen or pelvis

- Castration resistant prostatic adenocarcinoma; subjects must have current or
historical evidence of disease progression despite castrated level of testosterone (<
50 ng/dL) achieved by orchiectomy or luteinizing hormone-releasing hormone (LHRH)
agonist or antagonist therapy; disease progression has to be demonstrated by PSA
progression OR progression of measurable disease OR progression of non-measurable
disease as defined below:

- PSA: Two consecutive rising PSA values, at least 7 days apart

- Measurable disease: >= 20% increase in the sum of the longest diameters of all
measurable lesions or the development of any new lesions; the change will be
measured against the best response to castration therapy or against the
pre-castration measurements if there was no response

- Non-measurable disease:

- Soft tissue disease: The appearance of 1 or more lesions, and/or unequivocal
worsening of non-measurable disease when compared to imaging studies
acquired during castration therapy or against the pre-castration studies if
there was no response

- Bone disease: Appearance of 2 or more new areas of abnormal uptake on bone
scan when compared to imaging studies acquired during castration therapy or
against the pre-castration studies if there was no response; increased
uptake of pre-existing lesions on bone scan does not constitute progression

- White blood cell (WBC) >= 2,500 cells/uL

- Absolute neutrophil count (ANC) >= 1,000 cells/uL

- Platelet count >= 75,000 cells/uL

- Hemoglobin (HgB) >= 9.0 g/dL

- Creatinine =< 2.5 mg/dL

- Total bilirubin =< 2 x institutional upper limit of normal (ULN)

- Aspartate aminotransferase (AST, serum glutamic oxaloacetic transaminase [SGOT]) and
alanine aminotransferase (ALT, serum glutamate pyruvate transaminase [SGPT]) =< 2.5 x
institutional ULN

- Prior chemotherapy with 0-2 regimens is allowed

- Prior radiation therapy to prostate or prostate bed is allowed provided it occurred >
3 months before enrollment to the study

Exclusion Criteria:

- The presence of liver, or known brain metastases, malignant pleural effusions, or
malignant ascites

- Moderate or severe symptomatic metastatic disease, defined as a requirement for
treatment with opioid analgesics for cancer-related pain within 21 days prior to
registration

- Eastern Cooperative Oncology Group (ECOG) performance status > 2

- Treatment with chemotherapy within 3 months of registration

- Treatment with any of the following medications or interventions within 28 days of
registration:

- Systematic corticosteroids; use of inhaled, intranasal, and topical steroids is
acceptable

- Any other systemic therapy for prostate cancer (except for medical castration)

- History of external beam radiation therapy to metastatic sites within 1 year of
enrollment to the study

- Participation in any previous study involving sipuleucel-T

- Pathologic long-bone fractures, imminent pathologic long-bone fracture (cortical
erosion on radiography > 50%) or spinal cord compression

- Concurrent other malignancy with the exception of:

- Cutaneous squamous cell and basal carcinomas

- Adequately treated stage 1-2 malignancy

- Adequately treated stage 3-4 malignancy that has been in remission for >= 2 years
at the time of registration

- A requirement for systemic immunosuppressive therapy for any reason

- Any infection requiring parenteral antibiotic therapy or causing fever (temperature >
100.5 degrees Fahrenheit [F] or 38.1 degrees Celsius [C]) within 1 week prior to
registration

- Any medical intervention or other condition which, in the opinion of the principal
investigator could compromise adherence with study requirements or otherwise
compromise the study's objectives