Differential Effects of rhGH vs. rhIGF-1 on Cardiovascular Risk Factors

Study Overview
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Brief Summary
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The purpose of this study is to see if giving growth hormone or insulin-like growth factor-1 (IGF-1) to subjects with growth hormone deficiency effects cardiovascular risk factors differently.

Detailed Description
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Insulin-like growth factor-1 (IGF-1) in some circumstances acts as the mediator of the metabolic effects of growth hormone. However, there is some evidence to suggest that GH and IGF-1 act differently in some metabolic pathways. We will study the differences between GH and IGF-1 when provided as therapy for growth hormone deficiency in adults. Specifically we will be assessing if either medication impacts cardiovascular risk factors and if so do they impact risk factors differently. Ten adult males ages 18-65 who are growth hormone deficient on stable medications and with stable MRI findings (in the event of a known pituitary mass) will be recruited for the study.

Official Title
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Differential Effects of rhGH vs. rhIGF-1 on Cardiovascular Risk Factors in Adult Patients With Growth Hormone Deficiency

Conditions
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Growth Hormone Deficiency

Intervention / Treatment
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* Drug: Recombinant Human Growth Hormone
* Drug: Recombinant human IGF-1


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult male age 25-65 with documented growth hormone deficiency on stable doses x 3 months (at least) of any hormone replacement therapies and with stable MRIs x 2 years in the setting of a known pituitary mass. Exclusion Criteria: Female gender current GH use or GH use within three months of the study diabetes hypoglycemia liver or kidney disease use of drugs that could increase GH secretion (i.e. L-dopa) alcohol or substance abuse use of investigational drugs within four weeks of our study and use of supraphysiologic doses of steroids within the previous six months.

Ages Eligible for Study
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Minimum Age: 25 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: 1<br>Subject taking growth hormone | Drug: Recombinant Human Growth Hormone<br>* 300 mcg sc qd (which may be increased to 400 mcg sc qd after 4 weeks)<br>|
| Active Comparator: 2<br>Subject taking recombinant human IGF-1 | Drug: Recombinant human IGF-1<br>* 30 µg/kg for first 4 weeks (may be increased thereafter based on IGF-1 levels)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cardiovascular serum risk markers including lipids, IL-6, CRP and homocysteine |  | 2 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in visceral adiposity, intrahepatic and intramyocellular lipids |  | 2 months | 
| Changes in endothelial cell function |  | 2 months |