Weight Loss Study for Patients With Obesity Due to Craniopharyngioma or Other Brain Tumor

Study Overview
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Brief Summary
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The purpose of this study is to determine whether exenatide can cause weight loss in patients with a history of craniopharyngioma or other brain lesion.

Detailed Description
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Hypothalamic obesity occurs in up to 60% of patients with tumors in the hypothalamic region, most commonly craniopharyngiomas. Hypothalamic dysfunction can be due to tumor infiltration and as a consequence of surgery or radiation therapy. Survivors who develop obesity have greater morbidity and mortality than normal weight survivors. Prevention and treatment of obesity in this population is vital in order to decrease the morbidity and mortality from diabetes, stroke and myocardial infarction. Exenatide (Byetta®) is a GLP-1 homologue that was FDA approved for treatment of type 2 diabetes in 2005. It also decreases the rate of gastric emptying and increases satiety and has been shown to cause weight loss in some people. Exenatide may improve insulin sensitivity and satiety in patients with hypothalamic obesity but without the risks of bariatric surgery. The investigators hypothesize that treatment with exenatide will lead to weight loss in patients with hypothalamic obesity.

Official Title
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Effects of Exenatide on Body Weight in Patients With Hypothalamic Obesity

Conditions
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Obesity, Overweight, Craniopharyngioma

Intervention / Treatment
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* Drug: Exenatide


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18 to 40 years old History of craniopharyngioma or other lesion in the hypothalamic region Greater than 6 months post-treatment, including chemotherapy, surgery or radiation BMI >30 mg/m2 Females must be post-menopausal, surgically sterile or using effective birth control for at least 12 weeks Exclusion Criteria: HgbA1C >7% Use of diabetes medications other than metformin in the past 12 weeks, including exenatide Use of weight loss drugs or initiation of a weight loss program in past 3 months Impaired renal function or history of kidney transplant History of gall stones (unless s/p cholecystectomy), pancreatitis or alcoholism Personal or family history of medullary carcinoma of the thyroid or MEN type 2 History of gastroparesis or other gastric motility problems as exenatide decreases gastric motility History of allergic reaction to exenatide or other medication components Other significant comorbidities other than pituitary deficiencies Currently prescribed warfarin (exenatide may alter warfarin metabolism) Pregnant or lactating females History of severe hypoglycemia (BG <60 and requiring assistance from another person)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

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: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Exenatide<br>All patients received exenatide 10mcg BID x 50 weeks | Drug: Exenatide<br>* Treatment with exenatide 5 mcg twice daily for 4 weeks, then 10 mcg twice daily for 46 weeks.<br>* Other names: Byetta;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Body Weight (kg) | Change in body weight from baseline to end of study | baseline, 50 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Resting Energy Expenditure (Kcals Per Day) | Change in resting energy expenditure from baseline to 50 weeks | baseline, 50 weeks | 
| Visual Analogue Scales for Post-meal Satiety | Change in visual analogue scales scores from baseline to 50 weeks. Higher score indicates greater satiety (minimum 0, maximum 100). | baseline, 50 weeks | 
| Insulin Secretion (Area Under the Curve) | Change in insulin secretion from baseline | baseline, 50 weeks | 
| Gastric Emptying Rate (13C-octanoic Acid Isotope Excretion Half Life) | Change in the isotope excretion half life during a gastric emptying test at baseline and at 50 weeks | baseline, 50 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Exenatide, Byetta, Hypothalamic Obesity, Obesity, Craniopharyngioma