The Role of 5-alpha Reductase in Mediating Testosterone Actions
Public ClinicalTrials.gov record NCT00493987. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.
Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.
Brief summary
Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.
In normal men, the male hormone testosterone affects a number of things in the body including muscle function and sexual function. An enzyme in the body called 5-alpha reductase converts testosterone into another form called dihydrotestosterone (DHT) which has slightly different effects. The purpose of this study is to find out how different amounts of the two different forms of testosterone affect muscle function and sexual function in healthy young men like you. This will be done by giving the men participating in the study different combinations of hormone-related medication for 20 weeks and making measurements before, during and after the medications to look for changes in lean body tissue, muscle size, muscle strength and leg power, as well as sexual function and sexual activity in all participants.
Study identification
- NCT ID
- NCT00493987
- Recruitment status
- Completed
- Study type
- Interventional
- Phase
- Phase 4
- Lead sponsor
- Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
- NIH
- Enrollment
- 184 participants
Conditions and interventions
Conditions
Eligibility (public fields only)
- Age range
- 18 Years to 50 Years
- Sex
- Male
- Healthy volunteers
- Accepts healthy volunteers
This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.
Study timeline
- Start date
- Oct 31, 2002
- Primary completion
- Nov 30, 2009
- Completion
- Feb 28, 2010
- Last update posted
- May 12, 2010
2002 – 2010
United States locations
- U.S. sites
- 1
- U.S. states
- 1
- U.S. cities
- 1
| Facility | City | State | ZIP | Site status |
|---|---|---|---|---|
| Boston University Medical Center | Boston | Massachusetts | 02118 | — |
Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.
About this trial record page
- What this page shows
- Public field values for ClinicalTrials.gov record NCT00493987, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
- What this page does not do
- No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
- Where the data comes from
- Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
- Last refresh
- Last update posted May 12, 2010 · Synced Sep 6, 2026
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Open the official record
The complete protocol, eligibility criteria, and contact information for NCT00493987 live on ClinicalTrials.gov.