ObesityPhase 1NCT02646475
Metabolic Effects of Angiotensin-(1-7)
A Phase 1 study testing Angiotensin-(1-7) and Saline in people with Obesity and Insulin Resistance, run by Vanderbilt University at 1 site in United States.
Trial summary
The overall purpose of this study is to learn more about the metabolic effects of angiotensin-(1-7) in the insulin resistant state associated with obesity. Pharmacologic approaches to increase angiotensin-(1-7) levels or its actions are currently in development for treatment of metabolic-related diseases such as… Read more about this study
- Who is it for?
- Ages 18 to 60 years
- Conditions the study is for
- Obesity, Insulin Resistance, Hypertension
- What is being tested?
- Angiotensin-(1-7) and Saline
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 26 participants
- Where
- 1 siteUnited States
- Study dates
- Feb 2016to Dec 2029
- Phase
- Phase 1
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 60 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Males and females of all races between 18 and 60 years of age
- Obesity defined as body mass index between 30-40 kg/m2
- Insulin resistance defined as homeostasis model assessment 2 insulin resistance (HOMA2-IR) score >2.2
- Hypertension defined by two or more properly measured seated blood pressure readings >130/85 mmHg, or by use of anti-hypertensive medications. This blood pressure cutoff will allow us to include subjects with pre-hypertension.
- Able and willing to provide informed consent
Who cannot join
- Pregnancy or breast-feeding
- Current smokers or history of heavy smoking (>2 packs/day)
- History of alcohol or drug abuse
- Morbid obesity (BMI > 40 kg/m2)
- Previous allergic reaction to study medications
- Evidence of type I or type II diabetes (i.e. fasting glucose >126 mg/dl, use of anti-diabetic medications)
Show all 19Show fewer
- Cardiovascular disease other than hypertension such as myocardial infarction within 6 months prior to enrollment, presence of angina pectoris, significant arrhythmia, congestive heart failure (LV hypertrophy acceptable), deep vein thrombosis, pulmonary embolism, second or third degree heart block, mitral valve stenosis, aortic stenosis, or hypertrophic cardiomyopathy
- History of serious cerebrovascular disease such as cerebral hemorrhage, stroke, or transient ischemic attack
- History or presence of immunological or hematological disorders
- Impaired hepatic function [aspartate amino transaminase (AST) and/or alanine amino transaminase (ALT) > 2.0 x upper limit of normal range]
- Impaired renal function (serum creatinine >1.5 mg/dl)
- Anemia (hemoglobin <13.5 g/dl in males or <12.5 g/dl in females)
- Treatment with serotonin-norepinephrine reuptake inhibitors (SNRIs) or norepinephrine transporter (NET) inhibitors
- Treatment with phosphodiesterase 5 inhibitors
- Treatment with anticoagulants
- Treatment with chronic systemic glucocorticoid therapy (more than 7 consecutive days in 1 month)
- Treatment with any investigational drug in the 1 month preceding the study
- Inability to give, or withdraw, informed consent
- Other factors which in the investigator's opinion would prevent the subject from completing the protocol (i.e., clinically significant abnormalities on clinical, mental examination or laboratory testing or inability to comply with protocol)
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
Vanderbilt University Medical Center
Nashville, Tennessee, 37232
Cynthia Laws, MS, 615-421-1994, cynthial.laws@vumc.org
About this study
The overall purpose of this study is to learn more about the metabolic effects of angiotensin-(1-7) in the insulin resistant state associated with obesity. Pharmacologic approaches to increase angiotensin-(1-7) levels or its actions are currently in development for treatment of metabolic-related diseases such as obesity and type II diabetes, based on findings from animal studies. It is unclear if this peptide contributes to the regulation of metabolism in humans. The investigators will test if angiotensin-(1-7) infusion can improve insulin sensitivity measured by hyperinsulinemic-euglycemic clamp methods in individuals with obesity and insulin resistance. The investigators will also examine for changes in blood pressure and related hemodynamic and hormonal changes following angiotensin-(1-7) infusion.
Read the detailed description
This is an outpatient study that requires a screening visit and two study days in the Vanderbilt Clinical Research Center. Subjects will be asked to stop taking any medications for high blood pressure for at least 2 weeks prior to the study. Subjects will receive intravenous angiotensin-(1-7) or saline infusion on two separate study days, with each study day lasting approximately four hours. There will be at least one week of washout between study days. On each study day, subjects will be instrumented with two intravenous catheters (one for blood sampling and one for drug infusion), arm and finger blood pressure cuffs, and sticky patches to measure heart rate throughout the study. The investigators will take baseline measurements of blood pressure and heart rate and collect blood samples. The investigators will also perform a rebreathing test to measure the heart's pumping capacity. After baseline measurements, the investigators will infuse angiotensin-(1-7) or saline for 30 minutes, with blood pressure and heart rate measured every 10 minutes. At the end of 30 minutes, blood samples will be collected and the rebreathing test will be repeated. The investigators will continue the angiotensin-(1-7) or saline infusion for an additional 2 hours while performing a hyperinsulinemic-euglycemic clamp to measure insulin sensitivity.
- Being tested
- Angiotensin-(1-7), Saline
- Keywords
- renin-angiotensin system, angiotensin, insulin resistance, blood pressure
- Medical subject headings
- Obesity, Insulin Resistance, Hypertension, Metabolic Syndrome
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Angiotensin-(1-7)Drug
Also called Angiotensin I (1-7), Angiotensin I/II (1-7) Acetate
This is a biologically active endogenous angiotensin peptide. It may play an important role in the regulation of blood pressure by dilating blood vessels as well as a role in the regulation of insulin action.
SalineDrug
Also called normal saline, 0.9% sodium chloride
Normal saline will be used as a placebo comparator.
| Study group | Role | What they receive |
|---|---|---|
| Angiotensin-(1-7) | Experimental | Subjects will receive intravenous infusion of three ascending doses of Angiotensin-(1-7). The doses are 4, 8, and 16 ng/kg/min. Each dose will be maintained for 10 minutes. The highest dose of Angiotensin-(1-7) will be maintained for an additional 120 minutes during the hyperinsulinemic-euglycemic clamp, for a total of 150 minutes of infusion. Receives: Drug: Angiotensin-(1-7) |
| Saline | Placebo comparator | Subjects will receive an intravenous infusion of saline that is matched in volume to the Angiotensin-(1-7) study day. The saline infusion will also be maintained for a total of 150 minutes. Receives: Drug: Saline |
What is being measured
The primary outcome is the main question the study is designed to answer.
Whole-Body Insulin Sensitivity
Whole-body insulin sensitivity will be defined as the glucose infusion rate needed to maintain euglycemia during steady state (time=90 to 120 minutes) of the hyperinsulinemic-euglycemic clamp following angiotensin-(1-7) versus saline infusion. The insulin sensitivity will be corrected by body weight, lean body mass, and steady-state plasma insulin concentrations.
Measured: steady-state (time 90 to 120 minutes) during hyperinsulinemic-euglycemic clamp
Secondary outcomes (5)
Blood Pressure
The change in blood pressure following angiotensin-(1-7) versus saline infusion.
Measured: 150 minutes
Heart Rate
The change in heart rate following angiotensin-(1-7) versus saline infusion.
Measured: 150 minutes
Cardiac Output
The change in cardiac output following angiotensin-(1-7) versus saline infusion.
Measured: 150 minutes
Stroke Volume
The change in stroke volume following angiotensin-(1-7) versus saline infusion.
Measured: 150 minutes
Systemic Vascular Resistance
The change in systemic vascular resistance following angiotensin-(1-7) versus saline infusion.
Measured: 150 minutes
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Jan 2016 (estimated)
- Study startFeb 2016
- Primary completionDec 2029 (estimated)
- Study completionDec 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for ObesityStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 26 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Vanderbilt University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Italo Biaggioni, Vanderbilt University
- Investigators
- Alfredo Gamboa, MD, Principal investigator, Vanderbilt University Medical Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT02646475
- Sponsor's protocol ID
- 151699
- Status last verified
- May 2026
- First submitted
- 31 Dec 2015
- Last updated
- 22 May 2026
- Results posted
- No
- Data monitoring committee
- Yes
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 22 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Metabolic Effects of Angiotensin-(1-7)
- ClinicalTrials.gov ID
- NCT02646475
- Acronym / sponsor ID
- 151699
- Keywords
- renin-angiotensin system, angiotensin, insulin resistance, blood pressure
- Phase
- Phase 1
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 26 participants (estimated)
- Lead sponsor
- Vanderbilt UniversityUniversity, hospital or other
- Study start
- Feb 2016 (actual)
- Primary completion
- Dec 2029 (estimated)
- Study completion
- Dec 2029 (estimated)
- First posted
- 5 Jan 2016 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The overall purpose of this study is to learn more about the metabolic effects of angiotensin-(1-7) in the insulin resistant state associated with obesity. Pharmacologic approaches to increase angiotensin-(1-7) levels or its actions are currently in development for treatment of metabolic-related diseases such as obesity and type II diabetes, based on findings from animal studies. It is unclear if this peptide contributes to the regulation of metabolism in humans. The investigators will test if angiotensin-(1-7) infusion can improve insulin sensitivity measured by hyperinsulinemic-euglycemic clamp methods in individuals with obesity and insulin resistance. The investigators will also examine for changes in blood pressure and related hemodynamic and hormonal changes following angiotensin-(1-7) infusion.
Detailed description
This is an outpatient study that requires a screening visit and two study days in the Vanderbilt Clinical Research Center. Subjects will be asked to stop taking any medications for high blood pressure for at least 2 weeks prior to the study. Subjects will receive intravenous angiotensin-(1-7) or saline infusion on two separate study days, with each study day lasting approximately four hours. There will be at least one week of washout between study days. On each study day, subjects will be instrumented with two intravenous catheters (one for blood sampling and one for drug infusion), arm and finger blood pressure cuffs, and sticky patches to measure heart rate throughout the study. The investigators will take baseline measurements of blood pressure and heart rate and collect blood samples. The investigators will also perform a rebreathing test to measure the heart's pumping capacity. After baseline measurements, the investigators will infuse angiotensin-(1-7) or saline for 30 minutes, with blood pressure and heart rate measured every 10 minutes. At the end of 30 minutes, blood samples will be collected and the rebreathing test will be repeated. The investigators will continue the angiotensin-(1-7) or saline infusion for an additional 2 hours while performing a hyperinsulinemic-euglycemic clamp to measure insulin sensitivity.
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind (participant, investigator)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Angiotensin-(1-7) | Experimental | Drug: Angiotensin-(1-7)Subjects will receive intravenous infusion of three ascending doses of Angiotensin-(1-7). The doses are 4, 8, and 16 ng/kg/min. Each dose will be maintained for 10 minutes. The highest dose of Angiotensin-(1-7) will be maintained for an additional 120 minutes during the hyperinsulinemic-euglycemic clamp, for a total of 150 minutes of infusion. |
| Saline | Placebo comparator | Drug: SalineSubjects will receive an intravenous infusion of saline that is matched in volume to the Angiotensin-(1-7) study day. The saline infusion will also be maintained for a total of 150 minutes. |
Who may qualify
- Ages
- 18 to 60 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Males and females of all races between 18 and 60 years of age
- Obesity defined as body mass index between 30-40 kg/m2
- Insulin resistance defined as homeostasis model assessment 2 insulin resistance (HOMA2-IR) score >2.2
- Hypertension defined by two or more properly measured seated blood pressure readings >130/85 mmHg, or by use of anti-hypertensive medications. This blood pressure cutoff will allow us to include subjects with pre-hypertension.
- Able and willing to provide informed consent
Key exclusion criteria (19 listed)
- Pregnancy or breast-feeding
- Current smokers or history of heavy smoking (>2 packs/day)
- History of alcohol or drug abuse
- Morbid obesity (BMI > 40 kg/m2)
- Previous allergic reaction to study medications
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Angiotensin-(1-7)Also: Angiotensin I (1-7), Angiotensin I/II (1-7) AcetateThis is a biologically active endogenous angiotensin peptide. It may play an important role in the regulation of blood pressure by dilating blood vessels as well as a role in the regulation of insulin action. | Drug | Angiotensin-(1-7) |
| SalineAlso: normal saline, 0.9% sodium chlorideNormal saline will be used as a placebo comparator. | Drug | Saline |
Primary outcome
Whole-Body Insulin Sensitivity
Time frame: steady-state (time 90 to 120 minutes) during hyperinsulinemic-euglycemic clamp
Whole-body insulin sensitivity will be defined as the glucose infusion rate needed to maintain euglycemia during steady state (time=90 to 120 minutes) of the hyperinsulinemic-euglycemic clamp following angiotensin-(1-7) versus saline infusion. The insulin sensitivity will be corrected by body weight, lean body mass, and steady-state plasma insulin concentrations.
5 secondary outcomes
Blood Pressure
Time frame: 150 minutes
Heart Rate
Time frame: 150 minutes
Cardiac Output
Time frame: 150 minutes
Stroke Volume
Time frame: 150 minutes
Systemic Vascular Resistance
Time frame: 150 minutes
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 22 May 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Alfredo Gamboa, MD principal investigator
Vanderbilt University Medical Center
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1 study testing Angiotensin-(1-7) and Saline in people with Obesity and Insulin Resistance, run by Vanderbilt University at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 19 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 22 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Cynthia Laws, MS (615-421-1994, cynthia.laws@vumc.org), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Whole-Body Insulin Sensitivity (time frame: steady-state (time 90 to 120 minutes) during hyperinsulinemic-euglycemic clamp). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 22 May 2026.