← Back to Search


Metabolic Surgery for Type 2 Diabetes (IMPROVE-T2D Trial)

Phase 1 & 2
Waitlist Available
Led By Petter Bjornstad, MD
Research Sponsored by University of Colorado Denver School of Medicine Barbara Davis Center
Eligibility Criteria Checklist
Specific guidelines that determine who can or cannot participate in a clinical trial
Must have
Age 12-21 years
Obese youth with T2D (≥50 kg) scheduled for VSG
Must not have
Recent diabetic ketoacidosis or hyperosmolar hyperglycemia
Screening 3 weeks
Treatment Varies
Follow Up 60 min
Awards & highlights


This trial is testing whether or not a vertical sleeve gastrectomy, a type of weight loss surgery, can help improve Type 2 diabetes in youth by looking at changes in things like insulin resistance, glycemic control, beta-cell function, and cardiovascular health.

Who is the study for?
This trial is for obese youth aged 12-21 with Type 2 Diabetes, scheduled for vertical sleeve gastrectomy (VSG), and a BMI ≥35 kg/m2. Participants must have an HbA1c ≤12% and weigh less than 550 lbs. They cannot be on certain medications like diuretics or blood thinners that can't be stopped safely around the time of surgery.Check my eligibility
What is being tested?
The study tests how bariatric surgery (specifically VSG) affects pancreatic function, kidney health, and cardiovascular wellness in young people with Type 2 Diabetes. It includes measuring various body functions before and after surgery to see improvements.See study design
What are the potential side effects?
Potential side effects may include complications from renal biopsy such as bleeding or infection, reactions to contrast agents used in imaging tests, surgical risks associated with VSG including pain, infection, bleeding, and possible adverse reactions to anesthesia.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below
I am between 12 and 21 years old.
I am a young person with type 2 diabetes and weigh over 50 kg, scheduled for vertical sleeve gastrectomy.

Exclusion Criteria

You may be eligible for the trial if you check “No” for criteria below:
I have anemia.
I have recently had severe complications from diabetes.
My diabetes is not type 2.
I am not taking diuretics, SGLT blockers, daily NSAIDs or aspirin, sulfonamides, procaine, thiazolsulfone, probenecid, atypical antipsychotics or oral steroids regularly.
My kidney function is reduced with an eGFR below 40.
My blood pressure is often higher than 150/90 mmHg.
I was diagnosed with type 2 diabetes after turning 18.
I have kidney swelling or significant kidney stones.
I have a bleeding disorder or have had complications from bleeding.
I have kidney disease not caused by diabetes.
I have not started puberty.
One or both of my kidneys are smaller than 9 cm.
I have only one kidney.


Screening ~ 3 weeks
Treatment ~ Varies
Follow Up ~60 min
This trial's timeline: 3 weeks for screening, Varies for treatment, and 60 min for reporting.

Treatment Details

Study Objectives

Outcome measures can provide a clearer picture of what you can expect from a treatment.
Primary outcome measures
Effective Renal Plasma Flow (ERPF)
Glomerular Filtration Rate (GFR)
Pancreatic β-cell function
Secondary outcome measures
Aortic Stiffness & Wall Shear Stress
Renal Oxygenation
Renal Perfusion
Other outcome measures
Detachment and endothelial fenestration of glomeruli
Epigenetic profiling
Foot process width of glomeruli
+3 more

Trial Design

1Treatment groups
Experimental Treatment
Group I: Clinical InvestigationExperimental Treatment4 Interventions
Participants will include youth who are scheduled for, and will undergo, vertical sleeve gastrectomy (VSG) surgery at the Bariatric Surgery Clinic at Children's Hospital of Colorado. To understand how bariatric surgery affects renal function, all participants will undergo assessment of Glomerular Filtration Rate, (Iohexol Inj 300 mg/mL) and Effective Renal Plasma Flow (Aminohippurate Sodium Inj 20%). In addition, participants will undergo imaging assessment that includes renal Blood Oxygen Level Dependent (BOLD) and Arterial Spin Labeling (ASL) MRI.
First Studied
Drug Approval Stage
How many patients have taken this drug
Aminohippurate Sodium Inj 20%
Completed Phase 2
Renal Biopsy
Vertical Sleeve Gastrectomy
Iohexol Inj 300 mg/mL
Completed Phase 2

Find a Location

Who is running the clinical trial?

University of Colorado Denver School of Medicine Barbara Davis CenterLead Sponsor
16 Previous Clinical Trials
1,149 Total Patients Enrolled
University of Colorado, DenverLead Sponsor
1,758 Previous Clinical Trials
2,166,230 Total Patients Enrolled
Petter Bjornstad, MDPrincipal Investigator - University of Colorado School of Medicine
University of Colorado, Denver
6 Previous Clinical Trials
420 Total Patients Enrolled

Media Library

Vertical Sleeve Gastrectomy (Procedure) Clinical Trial Eligibility Overview. Trial Name: NCT03620773 — Phase 1 & 2
Type 2 Diabetes Research Study Groups: Clinical Investigation
Type 2 Diabetes Clinical Trial 2023: Vertical Sleeve Gastrectomy Highlights & Side Effects. Trial Name: NCT03620773 — Phase 1 & 2
Vertical Sleeve Gastrectomy (Procedure) 2023 Treatment Timeline for Medical Study. Trial Name: NCT03620773 — Phase 1 & 2
Type 2 Diabetes Patient Testimony for trial: Trial Name: NCT03620773 — Phase 1 & 2
~1 spots leftby Oct 2024