Study of Proscavax Vaccine in Patients With Localized Prostate Cancer vs Active Surveillance

This study will have 2 arms and patients will be randomized 2:1 into the Proscavax treatment
arm (Arm 1) versus the active surveillance arm (Arm 2).

In study Arm 1, 6 doses of the vaccine will be administered intradermally at weeks 1, 2, 3,
7, 11, and 15, followed by maintenance booster injections once every month which will
alternate between low dose IL-2 alone (at weeks 19, 27 and 35) and Proscavax vaccine (at
weeks 23, 31, 39) for 6 months.

In study Arm 2, patients will undergo active surveillance and will not receive any Proscavax
vaccine treatment.

Inclusion Criteria:

1. Histologically confirmed adenocarcinoma of the prostate.

2. Age ≥ 18 years.

3. Clinically localized prostate cancer:

- T1 (Cancer can only be seen under a microscope),

- NX (Regional lymph nodes cannot be assessed) or N0 (Cancer cannot be seen in the
lymph nodes),

- MX (Presence of distant metastasis cannot be assessed) or M0 (Cancer hasn't
spread to other parts of the body).

4. No previous treatment for prostate cancer (including hormonal therapy, radiation
therapy, surgery, or chemotherapy).

5. Eastern Cooperative Oncology Group (ECOG) Performance Status 0 or 1.

6. Patients must have the following laboratory values:

1. Absolute neutrophil count (ANC) > 1500/µL

2. Platelet count >100,000/µL

3. Hemoglobin > 10 g/dL

4. Bilirubin < 1.5 x upper limits of normal

5. Aspartate aminotransferase (AST) < 1.5 x upper limits of normal

6. Adequate estimated glomerular filtration rate (eGFR) > 30 mL/min per 1.73 m2
(adjusted for race)

7. Patient consent has been obtained according to local Institutional Review Board for
acquisition of research specimens.

8. Patient is accessible and compliant for follow-up.

9. Prostate biopsy requirements:

1. If diagnosis was within one year of baseline visit, participant must have at
least one biopsy with at least 10 cores.

2. If diagnosis was more than 1 year prior to baseline visit, participant must have
a minimum of 2 biopsies, one of which must be within 2 years prior to baseline
visit. Patients must have been diagnosed with prostate cancer within 2 years of
randomization (no history of prostate adenocarcinoma in any biopsies taken more
than 2 years prior to randomization).

10. Must have NCCN low or favorable-intermediate risk prostate cancer defined as:

- <50% of cores involved with cancer for eligibility and 50% or greater of cores
involved with cancer progression. Only cores from standard TRUS biopsy (not
MRI-guided cores) will be counted towards the number of cores involved.

- No primary Gleason pattern 4 (Gleason score 4+3) disease in any cores (TRUS or
MRI-guided)

- PSA less than 20 ng/mL

- No extracapsular extension (
11. Patients with female partners of childbearing potential must use at least one form of
Investigator-approved contraception while on-study and for 30 days after their last
administration of study investigational therapy. Acceptable birth control options
include:

1. surgical sterilization (patient and/or patient's partner),

2. approved hormonal contraceptives or therapies (such as birth control pills,
Depo-Provera, or Lupron Depot),

3. barrier methods (such as a condom or diaphragm) used with a spermicide, and

4. an intrauterine device (IUD).

Exclusion Criteria:

1. Unwillingness or inability (such as coagulopathy) to undergo serial prostate biopsy.

2. History of other malignancies, except: adequately treated non-melanoma skin cancer or
adequately treated superficial bladder cancer (Ta) or other solid tumors curatively
treated with no evidence of disease for > 5 years.

3. Evidence of metastatic prostate cancer.

4. Immune-compromised patients including but not limited to: systemic immune suppressive
medications within 6 weeks of enrolling; HIV-positive and below normal cluster of
differentiation 4 (CD4) lymphocytes (less than 500 cells per microliter). Patients
must be tested for HIV seropositivity and CD4 lymphocyte count to be eligible for the
study.

5. Inability to give consent.

6. Any condition that, according to the investigator, would make the patient an
inappropriate study candidate.

7. Patients with significant cardiac disease including heart failure that meets New York
Heart Association (NYHA) class II and IV definitions, history of myocardial infarction
within 6 months of study entry, uncontrolled dysrhythmias.

8. Patients with existing autoimmune disorders (IL-2 and GM-CSF carry risk of
exacerbating underlying autoimmune disorders).