Clinical trial Recruiting at 2 sites Early Phase 1 Interventional Ages 18 to 65

Understanding how gastric bypass surgery affects glucose metabolism

Official title: The Role of Glucagon Like Peptide-1 in Glucose Metabolism and Weight Loss Following Gastric Bypass Surgery

Run by The University of Texas Health Science Center at San Antonio · NCT01803451 · Data updated 2026-11-12

This study is trying to see how gastric bypass surgery helps people manage their blood sugar better by looking at certain hormones and their effects on insulin in patients who have had the surgery.

Quick facts

PhaseEarly Phase 1
Study typeInterventional
Ages18 Years to 65 Years
SexAll
Enrollment80 (estimated)
SponsorThe University of Texas Health Science Center at San Antonio
Academic / other
Locations2 sites (San Antonio, Texas and 1 other locations)
StatusRecruiting
StartedNovember 2005
Main results expectedAugust 2026
Study endsAugust 2027
Registry record updatedSeptember 9, 2025
Trial IDNCT01803451 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Ideal candidates include adults aged 18-65 who have undergone gastric bypass surgery and experience recurrent hypoglycemia.

Probably not a fit

Patients with significant anemia, diabetes (unless pre-operative for bariatric surgery), or gastrointestinal obstruction may not benefit from this study.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This project aims to explore the mechanisms by which gastric bypass surgery enhances glucose metabolism. It focuses on the role of incretin hormones in insulin secretion among patients who have undergone Roux-en-Y gastric bypass. The study involves three specific aims: assessing incretin hormones' impact on insulin secretion, comparing glucose tolerance in patients with and without hypoglycemia post-surgery, and quantifying the contribution of GLP-1 to the incretin effect after surgery. The methodology includes using an intravenous-oral hyperglycemic clamp to gather data.

Why it matters

Potential benefit: If successful, this study could lead to improved management of glucose metabolism in patients post-bariatric surgery.

How similar studies have gone: Other studies have shown promising results in understanding incretin hormones and glucose metabolism, making this approach both relevant and potentially impactful.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

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

Exclusion Criteria:

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

Where it's running

  • Texas Diabetes Institute - University Health System
    San Antonio, Texas, United States
    Recruiting
  • South Texas Veterans Health Care System
    San Antonio, Texas, United States
    Recruiting

Study contacts

  • Principal investigator: Marzieh Salehi, MD,MS — Marzieh Salehi
  • Study coordinator: Marzieh Salehi, MD MS
  • Email: salehi@uthscsa.edu
  • Phone: 210-567-6691

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

  • 5-week combined aerobic and strength exercise after bariatric surgery

    This test tries a 5-week combined aerobic and strength exercise program for adults recovering from sleeve gastrectomy or gastric bypass to see if it improves muscle quality, body composition, physical function, and quality of life.

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  • Effects of bariatric surgeries on glucose metabolism

    This study tests how gastric bypass and sleeve gastrectomy surgeries affect blood sugar control after meals in people with diabetes to see which surgery might work better.

    Recruiting at 2 sites Early Phase 1 The University of Texas Health Science Center at San Antonio · San Antonio, Texas and 1 other locations · NCT02823665

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  • Genetics of Skeletal Muscle Insulin Resistance

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    Recruiting The University of Texas Health Science Center at San Antonio · San Antonio, Texas · NCT07780513

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How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.