MedPath

Effect of PDE5 Inhibition on Adipose Metabolism in Humans

Phase 2
Recruiting
Conditions
Obesity
Interventions
Registration Number
NCT04684589
Lead Sponsor
Vanderbilt University Medical Center
Brief Summary

This is a randomized, double-blinded, placebo-controlled study of the effects of PDE5 inhibition with tadalafil on adipose tissue in obese individuals. Adipose metabolism will be measured using magnetic resonance imaging (MRI) scans and by aspirating a small amount of adipose to measure gene expression.

Detailed Description

The purpose of this study is to test whether tadalafil causes subcutaneous adipose tissue to have a "beige" phenotype. Participants will be randomized to either placebo or tadalafil for 12 weeks. Investigators will study adipose metabolism using MRI scans and aspiration of subcutaneous adipose from the abdomen. In addition to MRI scans at room temperature, the investigators will use a cooling protocol to test the combined effects of tadalafil and on adipose metabolism. Investigators will also measure the effects of the drug on body composition. In addition to the study visits, participants will wear an activity tracker (Fitbit) and log their dietary intake several times using an online tool. There will be a small amount of radiation exposure. Participants will be compensated for participation in this study.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
100
Inclusion Criteria
  • Adults
  • Obesity (BMI β‰₯ 30 kg/m2)
Exclusion Criteria
  • Age <19 or > 50
  • BMI < 30 kg/m2
  • Systolic blood pressure (SBP) < 100, > 150 mmHg
  • Current anti-hypertensive medication use, including diuretics
  • Current use of organic nitrates
  • Current use of PDE-5 inhibitors (sildenafil, tadalafil, vardenafil)
  • History of reaction to PDE-5 inhibitors
  • Known HIV infection
  • Use of medications that strongly alter CYP3A4 activity
  • History of myocardial infarction, angina, uncontrolled cardiac arrhythmia, stroke, transient ischemic attack, or seizure
  • Known non-arteritic ischemic optic retinopathy (NAIOR)
  • History of hearing loss
  • Estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m2 by the modified diet in renal disease (MDRD) equation
  • Hepatic transaminase (AST and ALT) levels greater than three times the upper limit of normal
  • Known pregnancy or breastfeeding or those unwilling to avoid pregnancy during the course of the study
  • History of priapism
  • Use in excess of four alcoholic drinks daily
  • History of diabetes mellitus or use of anti-diabetic medications
  • Known anemia (men, Hct < 38% and women, Hct <36%)
  • Menopause
  • Weight > 300 pounds
  • Individuals with circadian rhythm disorders, shift workers, or those who travel across time zones frequently

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
TadalafilTadalafil 20 MGSubjects will be randomized to one of two arms. 50 obese adult subjects will be randomized to the Tadalafil arm following the screening visit. Beginning at their baseline visit, they will receive an oral daily dose of Tadalafil (20mg) that they will take for 12 weeks (through their completion of the study). After randomization has occurred, the active comparator subjects will undergo the following visit protocol: screening visit, baseline visit, an interim visit (10 weeks post-baseline), and a 12-week visit.
PlaceboPlaceboSubjects will be randomized to one of two arms. 50 obese adult subjects will be randomized to the placebo arm following the screening visit. Beginning at their baseline visit, they will receive an oral daily dose of a placebo pill (20mg) that they will take for 12 weeks (through their completion of the study). After randomization has occurred, the placebo comparator subjects will undergo the following visit protocol: screening visit, baseline, an interim visit (10 weeks post-baseline), and a 12-week visit.
Primary Outcome Measures
NameTimeMethod
Thermoneutral FSF of WAT at the level of the umbilicus at 12 Weeks.12 weeks

MRI measurement of lipid content

Subcutaneous adipose tissue expression of UCP1 (normalized expression units)12 weeks

Measurement of gene expression in adipose sample

Secondary Outcome Measures
NameTimeMethod
Subcutaneous adipose tissue natriuretic peptide receptor expressionBaseline to 12 weeks

Measurement of gene expression in adipose sample

Thermoneutral fat signal fraction of brown adipose tissueBaseline to 12 weeks

MRI measurement of lipid content

Cold-exposed fat signal fraction of white adipose tissue and grown adipose tissueBaseline to 12 weeks

MRI measurement of lipid content

Subcutaneous adipose tissue gene expression of mitochondrial genes (normalized expression units)Baseline to 12 weeks

Measurement of gene expression in adipose sample

Trial Locations

Locations (1)

Vanderbilt University Medical Center

πŸ‡ΊπŸ‡Έ

Nashville, Tennessee, United States

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