This study will be carried out in a double-blinded fashion, so neither the subject nor the investigator will be aware of treatment assignment during the study. This protocol is designed to address the hypothesis that oral testosterone enanthate plus dutasteride can suppress the secretion of LH and FSH after four weeks of administration. In addition, we will compare the gonadotropin suppression mediated by a dose of testosterone enanthate (400 mg twice daily) that would be expected to maintain the serum testosterone in the normal range throughout the day, with the same dose (800 mg once daily) administered once daily. This larger once-daily dose is expected to result in a higher peak and lower trough by the end of the dosing interval. Secondary endpoints in this study include the ability of oral testosterone enanthate plus dutasteride to maintain short-term androgen-mediated endpoints such as mood and sexual function over the 4-week treatment period as well as weekly measures of safety, including blood counts, PSA and liver and kidney function.
