The purpose of this phase II trial is to determine the efficacy and safety of testosterone replacement therapy (TRT) in improving the symptoms of androgen deficiency and health-related quality of life in men with prostate cancer who have undergone radical prostatectomy.

The overall objective is to conduct a proof-of-concept double-blind, placebo-controlled, parallel group, randomized trial to determine the efficacy and safety of testosterone replacement therapy (TRT) in improving the symptoms of androgen deficiency (sexual symptoms, low energy, and physical dysfunction) and overall health-related quality of life in men with prostate cancer who have undergone radical prostatectomy for organ-localized disease (pT2,N0,M0), Gleason score < 7 (3+4), who have undetectable PSA (<0.1 ng/mL using a sensitive PSA assay) for > 2 years after radical prostatectomy, and who have androgen deficiency.

Inclusion Criteria:

Men with prostate cancer, who have Stage pT2, N0, M0 lesions (confined to the gland); Combined Gleason score of 7 (3+4 elements) or less; Preoperative PSA less than 10 ng/ml; Stable and undetectable PSA level (PSA less than 0.1 ng/mL using an assay that has a functional sensitivity of 0.1 ng/mL) for at least two years after radical prostatectomy.

• Age: 40 years and older
• Presence of symptoms related to sexual dysfunction, fatigue/low vitality, or physical dysfunction.
• An average of two fasting, early morning serum testosterone levels, measured by LC-MS/MS, less than 275 mg/dL and/or free testosterone by equilibrium dialysis <60 pg/mL. middle-aged and older men with mean testosterone levels > 300 ng/dL.
• Ability and willingness to provide informed consent

Exclusion Criteria:

• Men who have undergone radiation therapy
• Men receiving androgen deprivation therapy will be excluded.
• Hemoglobin <10 g/dL or >16.5 g/dL
• Severe untreated sleep apnea
• Allergy to sesame oil
• Uncontrolled heart failure
• Myocardial infarction, acute coronary syndrome, revascularization surgery, or stroke within 3 months
• Serum creatinine >2.5 mg/dL; ALT 3x upper limit of normal;
• Hemoglobin A1c >7.5% or diabetes requiring insulin therapy
• Body mass index (BMI) >40 kg/m2
• Untreated depression. Subjects with depression who have been on stable anti-depressant medication, or undergoing CBT for more than three months are eligible.
• Men with axis I psychiatric disorder, such as schizophrenia, will be excluded.
• Subjects who have used the following medications within the past 6 months: testosterone, DHEA, estrogens, GnRH analogs, antiandrogens, spironolactone, ketoconazole, rhGH, megestrol acetate, prednisone 20 mg daily or equivalent doses of other glucocorticoids for more than two weeks

Males with a history of prostate cancer who have undergone prostatectomy.