Post-bariatric SurgeryEarly Phase 1GLP-1NCT01803451
Glucagon-like Peptide 1, Glucose Metabolism and Gastric Bypass
A Early Phase 1 study testing exendin-(9-39) and exendin -(9-39) in people with Post-bariatric Surgery, run by The University of Texas Health Science Center at San Antonio at 2 sites in United States.
Trial summary
The overall goal of this project is to understand the mechanisms by which gastric bypass surgery improves glucose metabolism. The central hypothesis guiding this project is that the reconfiguration of intestinal transit with the Roux-en-Y will increase the release of insulinotropic GI hormones, termed incretins that… Read more about this study
- Who is it for?
- Ages 18 to 65 yearsHealthy volunteers can take part
- Conditions the study is for
- Post-bariatric Surgery
- What is being tested?
- exendin-(9-39) and exendin -(9-39)
- Type of treatment
- Pill or oral medicine, Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 80 participants
- Where
- 2 sitesUnited States
- Study dates
- Nov 2005to Aug 2027
- Phase
- Early 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 65 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- age 18-65
- healthy control without diabetes or active organ disease
- Individuals with bariatric surgery
- recurrent hypoglycemia post gastric bypass
Who cannot join
- pregnancy
- significant anemia
- diabetes currently unless pre-op for bariatric surgery procedure
- GI obstruction
Trial locations and contacts
2 sites in 1 country. Contact the study team or a site near you to ask about taking part.
United States2 sites, 2 recruiting
- Recruiting
Texas Diabetes Institute - University Health System
San Antonio, Texas, 78207
Jennifer Foster, MSN, 210-450-8696, fosterj6@uthscsa.edu
Marzieh Salehi, MD, MS, 210-567-6691, salehi@uthscsa.edu
- Recruiting
South Texas Veterans Health Care System
San Antonio, Texas, 78229
Marzieh Salehi, MD MS, 210-567-6691, salehi@uthscsa.edu
Jennifer Foster, 210-450-8696, fosterj6@uthscsa.edu
About this study
Official title: The Role of Glucagon Like Peptide-1 in Glucose Metabolism and Weight Loss Following Gastric Bypass Surgery
The overall goal of this project is to understand the mechanisms by which gastric bypass surgery improves glucose metabolism.
The central hypothesis guiding this project is that the reconfiguration of intestinal transit with the Roux-en-Y will increase the release of insulinotropic GI hormones, termed incretins that improve insulin secretion and glucose metabolism. The study is divided into three specific aims.
- To determine the role of incretin hormones on insulin secretion in patients with gastric bypass surgery using intravenous-oral hyperglycemic clamp.
- To compare incretin effect and glucose tolerance among patient who suffer from hypoglycemia after RYGB and asymptomatic surgical and non-surgical individuals.
- To quantify the contribution of GLP-1 to incretin effect enhancement following surgery.
Read the detailed description
The overall goal of this project is to understand the mechanisms by which gastric bypass surgery improves glucose metabolism.
The central hypothesis guiding this project is that the reconfiguration of intestinal transit with the Roux-en-Y will increase the release of insulinotropic GI hormones, termed incretins that improve insulin secretion and glucose metabolism. The study is divided into three specific aims.
- To determine the role of incretin hormones on insulin secretion in patients with gastric bypass surgery using intravenous-oral hyperglycemic clamp.
- To compare incretin effect and glucose tolerance among patient who suffer from hypoglycemia after RYGB and asymptomatic surgical and non-surgical individuals.
- To quantify the contribution of GLP-1 to incretin effect enhancement following surgery.
- Conditions
- Post-bariatric Surgery
- Being tested
- exendin-(9-39), exendin -(9-39)
- Keywords
- gastric bypass, glucose metabolism, hypoglycemia
- Medical subject headings
- Hypoglycemia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
exendin-(9-39)Drug
Also called no other name for exendin-(9-39)
hyperglycemic clamp-meal tolerance test is designed to assess insulin secretion before and after meal ingestion
exendin -(9-39)Drug
Also called no other name for exendin-(9-39)
2-day meal tolerance tests with labeled oral and IV glucose using exendin-(9-39) infusion are designed to evaluate the role of GLP-1 signaling on glucose tolerance and glucose kinetics.
| Study group | Role | What they receive |
|---|---|---|
| hyperglycemic clamp-Meal tolerance test | Experimental | these studies are to evaluate the effect of exendin-9 on insulin secretion before and after meal ingestion in patients after bariatric surgeries compared to non-surgical controls Receives: Drug: exendin-(9-39) |
| Labeled meal tolerance test | Experimental | The effect of GLP-1 receptor blockade on glucose tolerance and glucose kinetics are evaluated in the group patients with bariatric surgery vs. nonsurgical using exendin-9-39 infusion during one of the the 2-day dual tracer studies of meal tolerance test Receives: Drug: exendin -(9-39) |
What is being measured
The primary outcome is the main question the study is designed to answer.
The investigator measure glucose, islet and GI hormonal levels in response to meal ingestion as a composite measure and the percentage of contribution of GLP-1 contribution to postprandial insulin levels will also be calculated
Measured: up to 1 year (10 sessions)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted4 Mar 2013 (estimated)
- Study startNov 2005
- Primary completionAug 2026 (estimated)
- Study completionAug 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Post-bariatric SurgeryStudies of the same condition, open and under way.
- More trials run by The University of Texas Health Science Center at San AntonioThe sponsor's other registered studies.
- 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
- Early Phase 1
- Primary purpose
- Other
- Allocation
- Non-randomised
- Intervention model
- Factorial
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 80 participants (estimated)
Sponsor and investigators
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Marzieh Salehi, MD,MS, Principal investigator, Marzieh Salehi
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01803451
- Sponsor's protocol ID
- HSC20180070H
- Other IDs
- DK083554
- Acronym
- GLP-1
- Status last verified
- Sep 2025
- First submitted
- 20 Feb 2013
- Last updated
- 9 Sep 2025
- Results posted
- No
- Data monitoring committee
- Yes
Publications
Salehi M, Gastaldelli A, D'Alessio DA. Blockade of glucagon-like peptide 1 receptor corrects postprandial hypoglycemia after gastric bypass. Gastroenterology. 2014 Mar;146(3):669-680.e2. doi: 10.1053/j.gastro.2013.11.044. Epub 2013 Dec 4.
PubMed 24315990
Study at a glance
From the registry record, last updated by the sponsor on 9 Sep 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Role of Glucagon Like Peptide-1 in Glucose Metabolism and Weight Loss Following Gastric Bypass Surgery
- ClinicalTrials.gov ID
- NCT01803451
- Acronym / sponsor ID
- GLP-1 / HSC20180070H
- Conditions
- Post-bariatric Surgery
- Keywords
- gastric bypass, glucose metabolism, hypoglycemia
- Phase
- Early Phase 1
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 80 participants (estimated)
- Lead sponsor
- The University of Texas Health Science Center at San AntonioUniversity, hospital or other
- Study start
- Nov 2005
- Primary completion
- Aug 2026 (estimated)
- Study completion
- Aug 2027 (estimated)
- First posted
- 4 Mar 2013 (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 goal of this project is to understand the mechanisms by which gastric bypass surgery improves glucose metabolism.
The central hypothesis guiding this project is that the reconfiguration of intestinal transit with the Roux-en-Y will increase the release of insulinotropic GI hormones, termed incretins that improve insulin secretion and glucose metabolism. The study is divided into three specific aims.
- To determine the role of incretin hormones on insulin secretion in patients with gastric bypass surgery using intravenous-oral hyperglycemic clamp.
- To compare incretin effect and glucose tolerance among patient who suffer from hypoglycemia after RYGB and asymptomatic surgical and non-surgical individuals.
- To quantify the contribution of GLP-1 to incretin effect enhancement following surgery.
Detailed description
The overall goal of this project is to understand the mechanisms by which gastric bypass surgery improves glucose metabolism.
The central hypothesis guiding this project is that the reconfiguration of intestinal transit with the Roux-en-Y will increase the release of insulinotropic GI hormones, termed incretins that improve insulin secretion and glucose metabolism. The study is divided into three specific aims.
- To determine the role of incretin hormones on insulin secretion in patients with gastric bypass surgery using intravenous-oral hyperglycemic clamp.
- To compare incretin effect and glucose tolerance among patient who suffer from hypoglycemia after RYGB and asymptomatic surgical and non-surgical individuals.
- To quantify the contribution of GLP-1 to incretin effect enhancement following surgery.
Study design
- Primary purpose
- Other
- Allocation
- Non-randomised
- Intervention model
- Factorial
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| hyperglycemic clamp-Meal tolerance test | Experimental | Drug: exendin-(9-39)these studies are to evaluate the effect of exendin-9 on insulin secretion before and after meal ingestion in patients after bariatric surgeries compared to non-surgical controls |
| Labeled meal tolerance test | Experimental | Drug: exendin -(9-39)The effect of GLP-1 receptor blockade on glucose tolerance and glucose kinetics are evaluated in the group patients with bariatric surgery vs. nonsurgical using exendin-9-39 infusion during one of the the 2-day dual tracer studies of meal tolerance test |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- age 18-65
- healthy control without diabetes or active organ disease
- Individuals with bariatric surgery
- recurrent hypoglycemia post gastric bypass
Key exclusion criteria (4 listed)
- pregnancy
- significant anemia
- diabetes currently unless pre-op for bariatric surgery procedure
- GI obstruction
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 |
|---|---|---|
| exendin-(9-39)Also: no other name for exendin-(9-39)hyperglycemic clamp-meal tolerance test is designed to assess insulin secretion before and after meal ingestion | Drug | hyperglycemic clamp-Meal tolerance test |
| exendin -(9-39)Also: no other name for exendin-(9-39)2-day meal tolerance tests with labeled oral and IV glucose using exendin-(9-39) infusion are designed to evaluate the role of GLP-1 signaling on glucose tolerance and glucose kinetics. | Drug | Labeled meal tolerance test |
Primary outcome
The investigator measure glucose, islet and GI hormonal levels in response to meal ingestion as a composite measure and the percentage of contribution of GLP-1 contribution to postprandial insulin levels will also be calculated
Time frame: up to 1 year (10 sessions)
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 9 Sep 2025.
- Derived from this study: PubMed 24315990Salehi M, Gastaldelli A, D'Alessio DA. Blockade of glucagon-like peptide 1 receptor corrects postprandial hypoglycemia after gastric bypass. Gastroenterology. 2014 Mar;146(3):669-680.e2. doi: 10.1053/j.gastro.2013.11.044. Epub 2013 Dec 4.
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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.
Marzieh Salehi, MD,MS principal investigator
Marzieh Salehi
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Early Phase 1 study testing exendin-(9-39) and exendin -(9-39) in people with Post-bariatric Surgery, run by The University of Texas Health Science Center at San Antonio at 2 sites 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 4 inclusion and 4 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 9 Sep 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites 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. 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?
Early Phase 1 (sometimes called Phase 0) studies give a very small amount of a treatment to a few people, mainly to see how the body handles it.
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 Marzieh Salehi, MD MS (210-567-6691, salehi@uthscsa.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
The investigator measure glucose, islet and GI hormonal levels in response to meal ingestion as a composite measure and the percentage of contribution of GLP-1 contribution to postprandial insulin levels will also be calculated (time frame: up to 1 year (10 sessions)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT01803451, which also lists 1 linked publication.
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 9 Sep 2025.