Physiologic Response to Bariatric Surgery and the Impact of Adjunct Semaglutide in Adolescents (PRESSURE)

January 8, 2026 updated by: University of Colorado, Denver

Physiologic Response to Bariatric Surgery and the Impact of Adjunct Semaglutide - in Adolescents (the PRESSURE Trial)

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) can help people 12 to 24 years old who, between 1 and 2 years after bariatric surgery, have not lost as much weight as expected.

Study Overview

Study Type

Interventional

Enrollment (Estimated)

40

Phase

  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult

Accepts Healthy Volunteers

No

Description

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: ≤20% BMI loss at 1 year postop
  • If entering the Intervention phase from the existing patient pool: ≤20% BMI loss at 1-2 years 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 Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
No Intervention: Observational
Participants complete a set of standardized measures before bariatric surgery, 3 months postoperatively, and 12 months postoperatively.
Experimental: Active Medication + Standard Postoperative Care
Participants can be enrolled between 1 and 2 years postoperatively and will receive usual interdisciplinary postoperative care plus weekly subcutaneous injectable semaglutide for 26 weeks. Initial dose is 0.25mg and is escalated every 4 weeks as tolerated (0.5mg, 1.0mg, 1.7mg, 2.4mg) for a total exposure of 26 weeks.
Subcutaneous weekly injectable semaglutide
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.
Active Comparator: Standard Postoperative Care
Participants can be enrolled between 1 and 2 years postoperatively and will receive usual interdisciplinary 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.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Observational phase: Change in fasting glucagon-like peptide-1 (GLP1), measured by blood levels
Time Frame: Baseline, 12 months postoperatively
GLP1 levels are measured prior to an oral mixed meal tolerance test
Baseline, 12 months postoperatively
Observational phase: Change in stimulated glucagon-like peptide-1 (GLP1), measured by blood levels
Time Frame: Baseline, 12 months postoperatively
GLP1 levels are measured during an oral mixed meal tolerance test
Baseline, 12 months postoperatively
Observational phase: Change in insulin sensitivity (IS), measured by fasting blood insulin levels
Time Frame: Baseline, 12 months postoperatively
Fasting insulin levels are measured. IS is defined as 1/fasting insulin
Baseline, 12 months postoperatively
Observational phase: Change in percent fat free mass (FFM), measured by whole body dual-energy X-ray absorptiometry (DXA)
Time Frame: Baseline, 12 months postoperatively
Percent FFM is calculated as (1-Percent Fat Mass) from DXA
Baseline, 12 months postoperatively
Observational phase: Change in resting metabolic rate (RMR), measured by canopy indirect calorimetry
Time Frame: Baseline, 12 months postoperatively
RMR from canopy indirect calorimetry
Baseline, 12 months postoperatively
Observational phase: Change in 24 hour systolic blood pressure (BP), measured by ambulatory BP monitor
Time Frame: Baseline, 12 months postoperatively
Mean 24 hour systolic BP
Baseline, 12 months postoperatively
Observational phase: Change in indexed left ventricular mass (g/m to the 2.7th power), measured by echocardiogram
Time Frame: Baseline, 12 months postoperatively
Resting supine 2-dimensional echocardiogram
Baseline, 12 months postoperatively
Intervention phase: Change in BMI
Time Frame: Baseline, 26 weeks
[(BMI at 26 weeks-Weight at Intervention Baseline)]/(BMI at Intervention Baseline)] * 100
Baseline, 26 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in fasting glucagon-like peptide-1 (GLP1), measured by blood levels
Time Frame: Baseline, 3 months postoperatively
GLP1 levels are measured prior to an oral mixed meal tolerance test
Baseline, 3 months postoperatively
Change in stimulated glucagon-like peptide-1 (GLP1), measured by blood levels
Time Frame: Baseline, 3 months postoperatively
GLP1 levels are measured during an oral mixed meal tolerance test
Baseline, 3 months postoperatively
Change in fasting Peptide YY (PYY), measured by blood levels
Time Frame: Baseline, 3 months postoperatively
PYY levels are measured prior to an oral mixed meal tolerance test
Baseline, 3 months postoperatively
Change in fasting Peptide YY (PYY), measured by blood levels
Time Frame: Baseline, 12 months postoperatively
PYY levels are measured prior to an oral mixed meal tolerance test
Baseline, 12 months postoperatively
Change in stimulated Peptide YY (PYY), measured by blood levels
Time Frame: Baseline, 3 months postoperatively
Plasma PYY levels are measured during an oral mixed meal tolerance test
Baseline, 3 months postoperatively
Change in stimulated Peptide YY (PYY), measured by blood levels
Time Frame: Baseline, 12 months postoperatively
Plasma PYY levels are measured during an oral mixed meal tolerance test
Baseline, 12 months postoperatively
Change in fasting ghrelin, measured by blood levels
Time Frame: Baseline, 3 months postoperatively
Ghrelin levels are measured prior to an oral mixed meal tolerance test
Baseline, 3 months postoperatively
Change in fasting ghrelin, measured by blood levels
Time Frame: Baseline, 12 months postoperatively
Ghrelin levels are measured prior to an oral mixed meal tolerance test
Baseline, 12 months postoperatively
Change in stimulated ghrelin, measured by blood levels
Time Frame: Baseline, 3 months postoperatively
Ghrelin levels are measured during an oral mixed meal tolerance test
Baseline, 3 months postoperatively
Change in stimulated ghrelin, measured by blood levels
Time Frame: Baseline, 12 months postoperatively
Ghrelin levels are measured during an oral mixed meal tolerance test
Baseline, 12 months postoperatively
Change in insulin sensitivity (IS), measured by fasting blood insulin levels
Time Frame: Baseline, 3 months postoperatively
Fasting insulin levels are measured. IS is defined as 1/fasting insulin
Baseline, 3 months postoperatively
Change in percent fat free mass (FFM), measured by whole body dual-energy X-ray absorptiometry (DXA)
Time Frame: Baseline, 3 months postoperatively
Percent FFM is calculated as (1-Percent Fat Mass) from DXA
Baseline, 3 months postoperatively
Change in resting metabolic rate (RMR), measured by canopy indirect calorimetry
Time Frame: Baseline, 3 months postoperatively
RMR from canopy indirect calorimetry
Baseline, 3 months postoperatively
Change in 24 hour systolic blood pressure (BP), measured by ambulatory BP monitor
Time Frame: Baseline, 3 months postoperatively
Mean 24 hour systolic BP
Baseline, 3 months postoperatively
Change in indexed left ventricular mass (g/m to the 2.7th power), measured by echocardiogram
Time Frame: Baseline, 3 months postoperatively
Resting supine 2-dimensional echocardiogram
Baseline, 3 months postoperatively
Intervention Phase: Eligibility rate
Time Frame: Up to 150 weeks
(Patients meeting inclusion and exclusion criteria/Total patients screened)*100
Up to 150 weeks
Intervention Phase: Enrollment rate
Time Frame: Up to 154 weeks
(Participants enrolled/Patients eligible)*100
Up to 154 weeks
Intervention Phase: Retention rate
Time Frame: Up to 184 weeks
(Participants completing all intervention visits/Patients enrolled)*100
Up to 184 weeks
Intervention Phase: Mean maximum tolerated semaglutide dose
Time Frame: Baseline, 26 weeks
Mean maximum tolerated dose (mg) of weekly injectable semaglutide
Baseline, 26 weeks
Intervention Phase: Number of participants with at least one serious adverse event (AE) in the active medication group, measured by a count
Time Frame: Up to 30 weeks
Individual participants with serious AEs will be counted
Up to 30 weeks
Intervention Phase: Number of participants with an adverse event (AE) that leads to discontinuation of the medication, measured by a count
Time Frame: Up to 30 weeks
Participants experiencing an AE that leads to medication discontinuation will be counted
Up to 30 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Jaime Moore, MD MPH, University of Colorado, Denver

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

October 11, 2024

Primary Completion (Estimated)

September 1, 2027

Study Completion (Estimated)

October 1, 2027

Study Registration Dates

First Submitted

August 16, 2024

First Submitted That Met QC Criteria

August 26, 2024

First Posted (Actual)

August 28, 2024

Study Record Updates

Last Update Posted (Estimated)

January 12, 2026

Last Update Submitted That Met QC Criteria

January 8, 2026

Last Verified

January 1, 2026

More Information

Terms related to this study

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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