Official Title: “Oral Androgens in Man-4: Gonadotropin Suppression Medicated by Oral Testosterone Enanthate in Oil Plus Dutasteride (Short Title: Oral T-4)”

The protocol was 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

Study Type: Interventional

Study Design: Treatment, Randomized, Double Blind (Subject, Investigator), Dose Comparison, Crossover Assignment, Safety/Efficacy Study

Study Primary Completion Date: May 2007

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.

Intervention(s) in this Clinical Trial

• Drug: Testosterone Enanthate
  • Oral Testosterone 400 mg orally for 28 days
• Drug: Testosterone Enanthate
  • Oral Testosterone 800 mg orally for 28 days
• Drug: Dutasteride
  • dutasteride 0.5 mg orally, once daily for 28 days
• Other: placebo sesame oil
  • placebo sesame oil
• Drug: Dutasteride
  • 24.5 mg po once (Day 0)

Arms, Groups and Cohorts in this Clinical Trial

• Active Comparator: 1
  • Oral Testosterone enanthate in sesame oil, 400 mg po (orally), BID (twice daily) + dutasteride 0.5 mg orally, qd (once daily) for 28 days + dutasteride load 24.5 mg po once
• Active Comparator: 2
  • Oral Testosterone sesame oil, 800 mg po (orally), qd (in am daily) + placebo sesame oil (in pm daily) + dutasteride 0.5 mg orally, qd (once daily) for 28 days + dutasteride load 24.5 mg po once

Primary Measures

• Dutasteride can suppress the secretion of LH and FSH after four weeks of administration.
  • Time Frame: 4 weeks
    Safety Issue?: No

Secondary Measures

• The ability of oral testosterone enanthate plus dutasteride to maintain short-term androgen-medicated endpoints such as mood and sexual function over the 4-week treatment period
  • Time Frame: 4 weeks
    Safety Issue?: No

Inclusion Criteria:

• Males between 18 to 55 years of age
• In good general health based on normal screening evaluation (consisting of a medical history, physical exam, normal serum chemistry, hematology, and baseline hormone levels)
• Subject must agree not to participate in another research drug study for the duration of the study
• Subject must agree to not donate blood during the study
• Subject must be willing to comply with the study protocol and procedures

Exclusion Criteria:

• Men in poor general health, with abnormal blood results (clinical laboratory tests or hormone values)
• A known history of alcohol or drug abuse
• A history of testicular disease or severe testicular trauma,
• A history of bleeding disorders or current use of anti-coagulants
• A history of sleep apnea and/or major psychiatric disorders
• A body-mass index greater than 35,
• A history of or current use of testosterone
• Infertility

Gender Eligibility for this Clinical Trial: Male

Minimum Age for this Clinical Trial: 18 Years

Maximum Age for this Clinical Trial: 55 Years

Are Healthy Volunteers Accepted for this Clinical Trial?: Accepts Healthy Volunteers

Lead Sponsor: University of Washington

Overall Clinical Trial Officials and Contacts

John K Amory, MD, MPH Principal Investigator University of Washington  

Information obtained from ClinicalTrials.gov on November 20, 2008

Link to the current ClinicalTrials.gov record. http://clinicaltrials.gov/show/NCT00399165

Study ID Number: 06-2962-A

ClinicalTrials.gov Identifier: NCT00399165

Health Authority: United States: Food and Drug Administration

University of Washington