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28-Day Study of Testosterone Co-administered With Dutasteride in Hypogonadal Men

This study has been completed.
Information provided by (Responsible Party):
GlaxoSmithKline Identifier:
First received: November 8, 2006
Last updated: May 25, 2017
Last verified: May 2017
The combination of testosterone and dutasteride is intended for use in hypogonadal men. This study will evaluate the effect of 28-day repeat dosing of this combination with varying BID doses of testosterone (T), in combination with a fixed BID dose of dutasteride (D), as well as a testosterone alone arm, on T and D levels in the blood. The rationale is to look for the effects of each compound on the other, and to look for any safety problems that may result when the 2 drugs are given together.

Condition Intervention Phase
Hypogonadism Hypogonadism, Male Drug: Nanomilled testosterone Drug: Nanomilled dutasteride Drug: commercially available dutasteride Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: A Phase II, 28-Day, Randomized, Parallel-Group, Open-Label Study Evaluating the Efficacy and Safety of Twice Daily Oral Doses of Testosterone (150-400mg) Co-administered With 0.25mg Dutasteride Compared With 400mg Testosterone Alone and 0.25mg Dutasteride Alone in the Treatment of Hypogonadism

Resource links provided by NLM:

Further study details as provided by GlaxoSmithKline:

Primary Outcome Measures:
  • Safety measured by: monitoring laboratory tests changes in blood pressure and heart rate and heart activity on an ECG machine [ Time Frame: days 1 and 28 ]

Secondary Outcome Measures:
  • Testosterone concentration . [ Time Frame: on days 1 and 28 ]
  • Pharmacokinetics of testosterone, DHT, estradiol, estrone & dutasteride [ Time Frame: days 1 and 28. ]
  • Anabolic & androgenic Pharmacodynamic biomarkers [ Time Frame: pre- and post-dose ]

Enrollment: 43
Study Start Date: October 2006
Study Completion Date: October 2007
Primary Completion Date: October 2007 (Final data collection date for primary outcome measure)
Intervention Details:
    Drug: Nanomilled testosterone Drug: Nanomilled dutasteride Drug: commercially available dutasteride
    Other Names:
    • Nanomilled testosterone
    • Nanomilled dutasteride

Ages Eligible for Study:   18 Years to 70 Years   (Adult, Senior)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   No

Inclusion criteria:

  • Have a diagnosis of primary or secondary hypogonadism.
  • Have very low testosterone levels on 2 separate days.
  • Have a BMI within range of 18.5-35kg/m2.
  • Have not taken dutasteride for one year, or finasteride for the past 3 months.

Exclusion criteria:

  • Have had or have breast or prostate cancer, malabsorption syndrome, sleep apnea, psychiatric illness, polycythemia, or any other clinically significant current condition.
  • Are diabetic with an HbA1c >= 8.
  • Are taking any androgens, such as testosterone, saw palmetto.
  • Are taking ritonavir, indinavir, itraconazole, ketoconazole, erythromycin, warfarin, digoxin, cholestyramine, or any dietary/herbal/vitamin supplements.
  • Would donate more than 500 ML of blood over a 2 month period.
  • Physician does not think it is a good idea for you to participate in the trial. - Are unwilling to abstain from alcohol during the study.
  • Have a positive urine drug screen test.
  • Plan to change your smoking habits during the course of the trial.
  • Have Hepatitis C, Hepatitis B, or HIV.
  • Have a lab or EKG abnormality.
  • High or low blood pressure.
  • Have used of any investigational drug or device during the study or within 30 days prior to 1st dosing of study medication.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00398580

United States, California
GSK Investigational Site
Torrance, California, United States, 90502
United States, Kentucky
GSK Investigational Site
Louisville, Kentucky, United States, 40202
United States, Maryland
GSK Investigational Site
Baltimore, Maryland, United States, 21287
United States, North Carolina
GSK Investigational Site
Durham, North Carolina, United States, 27710
United States, Texas
GSK Investigational Site
San Antonio, Texas, United States, 78229
United States, Washington
GSK Investigational Site
Seattle, Washington, United States, 98108
GSK Investigational Site
Seattle, Washington, United States, 98195
Sponsors and Collaborators
Study Director: GSK Clinical Trials, M.D., Ph.D., FACP GlaxoSmithKline
  More Information

Responsible Party: GlaxoSmithKline Identifier: NCT00398580     History of Changes
Other Study ID Numbers: TDC106220
Study First Received: November 8, 2006
Last Updated: May 25, 2017

Keywords provided by GlaxoSmithKline:
Androgen deficiency

Additional relevant MeSH terms:
Gonadal Disorders
Endocrine System Diseases
Testosterone enanthate
Testosterone undecanoate
Testosterone 17 beta-cypionate
Hormones, Hormone Substitutes, and Hormone Antagonists
Physiological Effects of Drugs
Antineoplastic Agents, Hormonal
Antineoplastic Agents
Anabolic Agents
5-alpha Reductase Inhibitors
Steroid Synthesis Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Hormone Antagonists processed this record on September 21, 2017