Recruiting
Phase 1

Semaglutide

Sponsor:

University of Colorado, Denver

Code:

NCT06575738

Conditions

Obesity

Adolescent Obesity

Body-Weight Trajectory

Weight Loss Trajectory

Bariatric Surgery

Eligibility Criteria

Sex: All

Age: 12 - 24

Healthy Volunteers: Not accepted

Interventions

Injectable semaglutide or injectable tirzepatide

Standard postoperative care

Study Details

Brief summary:

The study plans to learn more about what happens to the body after bariatric surgery in people 12 to 24 years old. The study aims to understand why people respond differently to bariatric surgery and how to define success beyond weight loss alone. The study also plans to learn more about whether a medication (semaglutide or tirzepatide) can help people 12 to 24 years old who, between 6 and 24 months after bariatric surgery, have not lost as much weight as expected.

Conditions

Obesity

Adolescent Obesity

Body-Weight Trajectory

Weight Loss Trajectory

Bariatric Surgery

Study ID

NCT06575738

Start date

Oct 11, 2024

Status verified date

Jul, 2026

Completion date

Oct 1, 2027

Anticipated

Primary completion date

Sep 1, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 12 - 24

Healthy Volunteers: Not accepted

Observation Phase

Inclusion Criteria:

  • Signed and dated informed consent form
  • Willingness to comply with all study procedures and availability for the duration of the study
  • Male or female biological sex, age 12 through 24 years
  • In the preoperative pathway for vertical sleeve gastrectomy

Exclusion Criteria:

  • Planned Roux-en-Y gastric bypass
  • Hypothalamic obesity
  • Type 2 Diabetes
  • Current use of oral glucocorticoids (i.e. within 10 days of baseline visit)
  • Current use of insulin

Intervention/Treatment Phase

Inclusion Criteria:

  • Signed and dated informed consent form
  • Status post vertical sleeve gastrectomy
  • Male or female biological sex, age 12 through 24 years
  • Meeting minimum nutrition goals
  • Obesity: age 12-17 years: BMI ≥95th%ile for age/sex \| age 18-24 years: BMI ≥ 30kg/m\^2
  • If entering the Intervention phase from the Observational phase: ≤22% BMI loss at 6-24 months postop
  • If entering the Intervention phase from the existing patient pool: ≤22% BMI loss at 6-24 months postop

Exclusion Criteria:

  • Surgically correctable cause of suboptimal postoperative weight loss
  • Known hypersensitivity to any component of semaglutide
  • Personal or family history of medullary thyroid carcinoma
  • Personal history of multiple endocrine neoplasia type 2
  • Hypothalamic Obesity
  • Type 2 Diabetes
  • History of pancreatitis
  • Uncontrolled hypertension
  • Clinically significant arrhythmia or heart disease that could be exacerbated by increased heart rate
  • Malignant neoplasm within the last 5 years
  • Untreated thyroid disorder
  • Tanner Stage 1
  • Baseline alanine transaminase (ALT) or aspartate aminotransferase (AST) ≥ 5x upper limit of normal
  • Baseline Creatinine >1.2mg/dL
  • Active treatment for bulimia nervosa
  • Active major psychiatric disorder limiting informed consent
  • Suicidal ideation of type 4 or 5 on Columbia-Suicide Severity Rating Scale (C-SSRS)
  • Intentional self-harm within the previous 1 month
  • Severe unmanaged depression, defined by Center for Epidemiological Studies Depression (CESD) score of 26 or greater and by clinical evaluation
  • Recent change to concomitant medications for hypertension, dyslipidemia, depression or anxiety (<4 weeks prior to enrollment)
  • Use of oral glucocorticoids (within 10 days of baseline visit)
  • Use of metformin (within 3 months of baseline visit)
  • Use of insulin secretagogues (within 4 half-lives of the medication of baseline visit)
  • Current use of insulin
  • Use of anti-obesity medications (within 4 half-lives of the medication of baseline visit)
  • Current pregnancy
  • For females of reproductive potential: Plan to become pregnant in the next 8 months
  • For females of reproductive potential: Not on contraception (i.e. two forms of birth control for example oral birth control pills and condoms) for at least 1 month prior to enrollment and agreement to use these during study participation and for an additional 8 weeks after the final dose of study medication

Study Design

Enrollment

40 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

no intervention: Observational

Participants complete a set of standardized measures before bariatric surgery, 3 months postoperatively, and 6 months postoperatively.

experimental: Active Medication + Standard Postoperative Care

Participants can be enrolled between 6 and 24 months postoperatively and will receive usual interdisciplinary postoperative care plus weekly subcutaneous injectable semaglutide or tirzepatide for 26 weeks. Initial dose is 0.25mg (semaglutide) or 2.5mg (tirzepatide) and is escalated every 4 weeks as tolerated up to the max dose of 2.4mg for semaglutide or 15mg for tirzepatide for a total exposure of 26 weeks.

active comparator: Standard Postoperative Care

Participants can be enrolled between 6 to 24 months postoperatively and will receive usual interdisciplinary postoperative care.

Interventions

Injectable semaglutide or injectable tirzepatide

Subcutaneous weekly injectable medication

Standard postoperative care

Standard postoperative care consists of behaviorally-focused interventions delivered by the interdisciplinary Bariatric Surgery Center team targeting nutrition, physical activity, sleep, and mental health at standard postoperative intervals.

Primary outcome measure

  • Observational phase: Change in fasting glucagon-like peptide-1 (GLP1), measured by blood levels [ Time Frame: Baseline, 6 months postoperatively ]
  • Observational phase: Change in stimulated glucagon-like peptide-1 (GLP1), measured by blood levels [ Time Frame: Baseline, 6 months postoperatively ]
  • Observational phase: Change in insulin sensitivity (IS), measured by fasting blood insulin levels [ Time Frame: Baseline, 6 months postoperatively ]
  • Observational phase: Change in percent fat free mass (FFM), measured by whole body dual-energy X-ray absorptiometry (DXA) [ Time Frame: Baseline, 6 months postoperatively ]
  • Observational phase: Change in resting metabolic rate (RMR), measured by canopy indirect calorimetry [ Time Frame: Baseline, 6 months postoperatively ]
  • Observational phase: Change in 24 hour systolic blood pressure (BP), measured by ambulatory BP monitor [ Time Frame: Baseline, 6 months postoperatively ]
  • Observational phase: Change in indexed left ventricular mass (g/m to the 2.7th power), measured by echocardiogram [ Time Frame: Baseline, 6 months postoperatively ]
  • Intervention phase: Change in BMI [ Time Frame: Baseline, 26 weeks ]

Central Contacts and Locations

Central contacts

Jaime Moore, MD MPH

303-724-8419jaime.moore@cuanschutz.edu

Locations

Childrens Hospital Colorado

Recruiting

Aurora, Colorado, United States, 80045

Contacts

Jaime Moore, MD MPH

303-724-8419jaime.moore@cuanschutz.edu

More Information

Sponsor

University of Colorado, Denver

Last update posted

Jul 15, 2026

Last verified

Jul, 2026

Keywords

  • Obesity
  • Anti-obesity medication
  • Bariatric Surgery
  • Bariatric Surgery Post Operative Outcomes
  • Semaglutide
  • Sleeve gastrectomy

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of Colorado, Denver on 2026-07-15.