NCT01803451

Brief 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 improve insulin secretion and glucose metabolism. The study is divided into three specific aims.

  1. 1.To determine the role of incretin hormones on insulin secretion in patients with gastric bypass surgery using intravenous-oral hyperglycemic clamp.
  2. 2.To compare incretin effect and glucose tolerance among patient who suffer from hypoglycemia after RYGB and asymptomatic surgical and non-surgical individuals.
  3. 3.To quantify the contribution of GLP-1 to incretin effect enhancement following surgery.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
80

participants targeted

Target at P75+ for early_phase_1

Timeline
15mo left

Started Nov 2005

Longer than P75 for early_phase_1

Geographic Reach
1 country

2 active sites

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress94%
Nov 2005Aug 2027

Study Start

First participant enrolled

November 1, 2005

Completed
7.3 years until next milestone

First Submitted

Initial submission to the registry

February 20, 2013

Completed
12 days until next milestone

First Posted

Study publicly available on registry

March 4, 2013

Completed
13.4 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

August 1, 2026

Expected
1 year until next milestone

Study Completion

Last participant's last visit for all outcomes

August 1, 2027

Last Updated

September 9, 2025

Status Verified

September 1, 2025

Enrollment Period

20.8 years

First QC Date

February 20, 2013

Last Update Submit

September 8, 2025

Conditions

Post-bariatric Surgery

Keywords

gastric bypassglucose metabolismhypoglycemia

Outcome Measures

Primary Outcomes (1)

  • 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

    up to 1 year (10 sessions)

Study Arms (2)

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

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

Drug: exendin -(9-39)

Interventions

exendin-(9-39)DRUG

hyperglycemic clamp-meal tolerance test is designed to assess insulin secretion before and after meal ingestion

Also known as: no other name for exendin-(9-39)
hyperglycemic clamp-Meal tolerance test
exendin -(9-39)DRUG

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.

Also known as: no other name for exendin-(9-39)
Labeled meal tolerance test

Eligibility Criteria

Age18 Years - 65 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • age 18-65
  • healthy control without diabetes or active organ disease
  • Individuals with bariatric surgery
  • recurrent hypoglycemia post gastric bypass

You may not qualify if:

  • pregnancy
  • significant anemia
  • diabetes currently unless pre-op for bariatric surgery procedure
  • GI obstruction

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (2)

Texas Diabetes Institute - University Health System

San Antonio, Texas, 78207, United States

RECRUITING

South Texas Veterans Health Care System

San Antonio, Texas, 78229, United States

RECRUITING

Related Publications (1)

  • 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.

    PMID: 24315990DERIVED

MeSH Terms

Conditions

Hypoglycemia

Interventions

exendin (9-39)

Condition Hierarchy (Ancestors)

Glucose Metabolism DisordersMetabolic DiseasesNutritional and Metabolic Diseases

Study Officials

  • Marzieh Salehi, MD,MS

    Marzieh Salehi

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Marzieh Salehi, MD MS

CONTACT

210-567-6691salehi@uthscsa.edu

Jennifer Foster, MSN

CONTACT

210-450-8696fosterj6@uthscsa.edu

Study Design

Study Type
interventional
Phase
early phase 1
Allocation
NON RANDOMIZED
Masking
SINGLE
Who Masked
PARTICIPANT
Purpose
OTHER
Intervention Model
FACTORIAL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

February 20, 2013

First Posted

March 4, 2013

Study Start

November 1, 2005

Primary Completion (Estimated)

August 1, 2026

Study Completion (Estimated)

August 1, 2027

Last Updated

September 9, 2025

Record last verified: 2025-09

Locations

US(2)