Inclusion Criteria:

1. Performance status ≤2

2. Documented adenocarcinoma of the prostate with histologic confirmation

3. Treated with continuous androgen ablative therapy (either surgical castration or LHRH
agonist for ≥ 1 year)

4. Documented castrate level of serum testosterone (<50 ng/dl)

5. Evidence of rising PSA on two successive dates > 1 month apart

6. Treatment with ≤ 2 prior chemotherapeutic regimens allowed

7. Treatment with ≤2 prior second line hormone therapies allowed.

8. Prior treatment with ketoconazole is allowed.

9. Patients must be withdrawn from antiandrogens for ≥ 6 weeks and have documented PSA
increase after the 6 week withdrawal period.

10. Patients with rising PSA only or ≤ 5 sites of asymptomatic bone metastases and < 10
total sites of disease including bone and soft tissue documented within 28 days of
enrollment on trial.

11. Patients will considered for repeat treatment with testosterone if they meet the
following criteria:

1. Had either PSA decline from baseline following treatment with testosterone or
had return of PSA levels to pretreatment baseline once serum testosterone
reached a castrate level.

2. Must continue to meet inclusion/exclusion criteria as described above

3. Must have been off testosterone therapy for ≥ 3 months

4. Must have castrate level of serum testosterone

5. Must have evidence of rising PSA on two occasions at least 2 weeks apart

6. Are allowed to have had additional treatment with up to 2 additional hormonal
therapies that include anti-androgens (e.g. flutamide, bicalutamide, nilutamide,
enzalutamide), CYP17 inhibitors (e.g. ketoconazole, abiraterone acetate) or
other investigational hormonal therapies.

Exclusion Criteria:

1. Evidence of disease in sites or extent that, in the opinion of the investigator,
would put the patient at risk from therapy with testosterone (e.g. femoral metastases
with concern over fracture risk, spinal metastases with concern over spinal cord
compression, lymph node disease with concern for ureteral obstruction)

2. Abnormal liver function (bilirubin, AST, ALT ≥ 2 x upper limit of normal)

3. Abnormal kidney function (serum creatinine ≥ 2 x upper limit of normal)

4. Inability to provide informed consent