PROS-1-Male Hormonal Contraceptive Regimens on Prostate Tissue

The purpose of this research study is to understand the effects of testosterone on the prostate. This knowledge will be used to help in the development of a safe male hormonal contraception.

We will be administering three drugs in this study: Testim (testosterone (T) gel), dutasteride (which affects testosterone break down) and Depomedoxyprogesterone (DMPA, a progestin). We want to see their effects on levels of hormones in the blood and prostate. In addition, we will be examining the effects of these drugs on the expression of genes within the prostate. DMPA suppresses LH and FSH, which are hormones made by the pituitary gland, thus blocking the signal from the brain that causes the testes to make testosterone. Prolonged (> 1 month) low levels of LH and FSH cause decreased sperm production in normal men. However, men may experience some side effects from the low levels of testosterone caused by DMPA; adding testosterone to DMPA eliminates these side effects while more effectively blocking LH and FSH release and sperm production. This combination of drugs is a promising male contraceptive regimen. However, the effect of these drugs on the prostate is not known. Some studies suggest that testosterone administration may promote prostate growth. Dutasteride blocks the conversion of testosterone to dihydrotestosterone and is used to treat men with enlarged prostates. Dutasteride shrinks the prostate. It is possible that combining testosterone and dutasteride may be an effective part of a male hormonal contraceptive regime. Therefore, further studies examining the effect of testosterone, DMPA and dutasteride on the prostate are needed.

Inclusion criteria

• Men in good health, and without a history of chronic androgen therapy or known history of gonadal or prostate abnormalities.

• PSA ≤ 2.
• Age 25-55 years
• Ability to understand the study,study procedures and provide consent
• Normal serum total T, LH, FSH, urine analyses, and sperm count > or equal to 15million/ml
• International Prostate Symptom Score (IPSS) < 10
• Normal seminal fluid analysis (>20 million sperm/ml)
• Agree not to donate blood during the treatment and recovery periods

Exclusion criteria

• A history or evidence of prostate or breast cancer
• History of invasive therapy for BPH
• History of acute urinary retention
• Current or past treatment with a 5α-reductase inhibitor
• History of anti/androgenic drugs or drugs that interfere with steroid metabolism within past 3 months
• Severe systemic illness (renal, liver, cardiac, lung disease, cancer, poorly controlled diabetes)
• Known untreated obstructive sleep apnea
• Hematocrit > 52%
• Skin disease that might interfere with T gel absorption
• Hypersensitivity to any of the drugs used in the study
• History of a bleeding disorder or anticoagulation
• History of drug or alcohol abuse within 12 months
• History of infertility or desire for fertility within 12 months, or current pregnant partner
• A first-degree relative (i.e. father, brother) with a history of prostate cancer
• Abnormal digital rectal examination or prostate ultrasound