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Completed Phase 1 Interventional

Growth Hormone Administration and the Human Immune System

ClinicalTrials.gov ID: NCT00663611

Public ClinicalTrials.gov record NCT00663611. 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.

ClinicalTrials.gov public records Last synced Sep 1, 2026, 6:28 PM EDT

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.

Background: \- In elderly individuals, an age-associated decline in the immune system s ability to function is believed to contribute to increased incidence of infection, autoimmune disorders, and cancer. This decline in immune system function may be related to the decline in the body s production of growth hormone, which helps regulate human development and may contribute to the health of the immune system. Researchers are interested in studying whether growth hormone, given as an infusion over time, can improve the function of the immune system and other body systems associated with good health. Objectives: \- To study the effects of growth hormone administration on the immune systems of healthy men. Eligibility: \- Healthy men between 25 and 50 years of age. Design: * This protocol will involve three separate studies: Study I, Study IB, and Study II. Participants in Study I and Study IB may participate in Study II as directed by the researchers. * Participants will be screened with a full medical history and physical examination, and will provide blood, urine, and stool samples; have a glucose tolerance test; and have other tests as required by the researchers. * Participants will have an infusion pump with a small catheter inserted beneath the skin to administer the study chemicals (either growth hormone or placebo). * Study I and Study IB participants will receive pulses of growth hormone through the infusion pump at regular intervals to monitor the body s response to the hormone. Study IB participants will receive a higher dose of growth hormone than Study I participants. * Throughout the study period, all participants will have frequent blood and urine tests, as well as tests of glucose tolerance and metabolism, imaging studies, and other tests as required by the researchers. * Study II participants will be divided into two groups. The first group will receive pulses of either growth hormone or placebo infusion at intervals throughout the day for 4 weeks, followed by an 8-week period without infusions. The second group will receive conventional once-a-day infusion of growth hormone or placebo for 4 weeks, followed by an 8-week period without infusions. * Throughout the study period, all participants will have frequent blood and urine tests, as well as tests of glucose tolerance and metabolism, imaging studies, and other tests as required by the researchers.

Study identification

NCT ID
NCT00663611
Recruitment status
Completed
Study type
Interventional
Phase
Phase 1
Enrollment
66 participants

Conditions and interventions

Interventions

Drug

Eligibility (public fields only)

Age range
25 Years to 50 Years
Sex
Male
Healthy volunteers
Healthy volunteers not accepted

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Oct 18, 2006
Primary completion
Oct 5, 2014
Completion
Oct 5, 2014
Last update posted
Aug 31, 2026

2006 – 2014

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
National Institute of Aging, Clinical Research Unit Baltimore Maryland 21224

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 NCT00663611, 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 Aug 31, 2026 · Synced Sep 1, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT00663611 live on ClinicalTrials.gov.

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