NCT02207777

Brief Summary

For this purpose, we will compare the effects of targeted 16-18% (with a range of 16-25%) weight loss induced by Roux-en-Y Gastric bypass (RYGB) surgery with the same weight loss induced by a low-calorie diet (LCD) on liver and skeletal muscle insulin sensitivity, beta-cell function, and 24-hour metabolic homeostasis in obese subjects with or without T2D.

Trial Health

87
On Track

Trial Health Score

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

Enrollment
65

participants targeted

Target at P50-P75 for not_applicable obesity

Timeline
Completed

Started Aug 2014

Longer than P75 for not_applicable obesity

Geographic Reach
1 country

1 active site

Status
completed

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

First Submitted

Initial submission to the registry

July 31, 2014

Completed
1 day until next milestone

Study Start

First participant enrolled

August 1, 2014

Completed
3 days until next milestone

First Posted

Study publicly available on registry

August 4, 2014

Completed
4.6 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

March 1, 2019

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

March 1, 2019

Completed
Last Updated

July 20, 2025

Status Verified

July 1, 2025

Enrollment Period

4.6 years

First QC Date

July 31, 2014

Last Update Submit

July 17, 2025

Conditions

Keywords

ObesityRoux-en-Y gastric bypass (RYGB)Type 2 DiabetesWeight LossLow-Calorie Diet

Outcome Measures

Primary Outcomes (1)

  • Changes in hepatic insulin sensitivity

    The outcome will be assessed by hyperinsulinemic-euglycemic-pancreatic-clamp procedure before and after weight loss.

    6 months (before and after targeted weight loss)

Secondary Outcomes (10)

  • Changes in skeletal muscle and adipose tissue insulin sensitivity

    6 months (before and after targeted weight loss)

  • Changes in Beta-cell function

    6 months (before and after targeted weight loss)

  • Changes in glucose kinetics (glucose concentration and rate of appearance into the systemic circulation) in response to mixed-meal ingestion

    6 months (before and after targeted weight loss)

  • Changes in 24-hour plasma glucose profile

    6 months (before and after targeted weight loss)

  • Changes in 24-hour plasma insulin profile

    6 months (before and after targeted weight loss)

  • +5 more secondary outcomes

Study Arms (2)

Roux-en-Y gastric bypass (RYGB)

EXPERIMENTAL

Subjects in this group are scheduled to undergo roux-en-Y gastric bypass surgery to obtain approximately 16-18% (with a range of 16-25%) weight loss.

Procedure: Roux-en-Y gastric bypass surgery

Low-calorie diet

ACTIVE COMPARATOR

Subjects in this group will participate in a low-calorie diet intervention to obtain approximately 16-18% (with a range of 16-25%) weight loss.

Behavioral: Low-calorie diet

Interventions

A surgical procedure to help subjects lose approximately 16-18% (with a range of 16-25%) of their body weight.

Roux-en-Y gastric bypass (RYGB)

Subjects will meet with a dietitian and/or behaviorist over approximately 6 months to lose approximately 16-18% (with a range of 16-25%) of their body weight.

Low-calorie diet

Eligibility Criteria

Age25 Years - 65 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • For RYGB group:
  • Scheduled for this bariatric surgery
  • Body Mass Index (BMI) 34-55 kg/m²
  • Type 2 Diabetes
  • Signed informed consent
  • For Low-Calorie Diet group:
  • BMI 34-55 kg/m²
  • Type 2 Diabetes and Non-Diabetics
  • Signed informed consent

You may not qualify if:

  • For both RYGB \& Low-Calorie Diet groups
  • Regular use of tobacco products
  • Previous intestinal resection
  • Pregnant or breastfeeding
  • Evidence of significant organ system dysfunction or disease other than T2D
  • Use of any medication that might, in the opinion of the investigator, affect metabolic function
  • Exercise ≥90 minutes per week

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Washington University School of Medicine

St Louis, Missouri, 63110, United States

Location

Related Publications (5)

  • Petersen MC, Yoshino M, Smith GI, Gaspar RC, Kahn M, Samovski D, Shulman GI, Klein S. Effect of Weight Loss on Skeletal Muscle Bioactive Lipids in People With Obesity and Type 2 Diabetes. Diabetes. 2024 Dec 1;73(12):2055-2064. doi: 10.2337/db24-0083.

    PMID: 39264820BACKGROUND
  • Samovski D, Smith GI, Palacios H, Pietka T, Fuchs A, Patti GJ, Nawaz A, Kahn CR, Klein S. Effect of Marked Weight Loss on Adipose Tissue Biology in People With Obesity and Type 2 Diabetes. Diabetes Care. 2025 Aug 1;48(8):1342-1351. doi: 10.2337/dc24-2739.

    PMID: 40208704BACKGROUND
  • Smith GI, Klein S. Plasma endotrophin levels correlate with insulin resistance in people with obesity. J Clin Invest. 2025 Apr 22;135(12):e190577. doi: 10.1172/JCI190577. eCollection 2025 Jun 16. No abstract available.

    PMID: 40261704BACKGROUND
  • Yoshino M, Kayser BD, Yoshino J, Stein RI, Reeds D, Eagon JC, Eckhouse SR, Watrous JD, Jain M, Knight R, Schechtman K, Patterson BW, Klein S. Effects of Diet versus Gastric Bypass on Metabolic Function in Diabetes. N Engl J Med. 2020 Aug 20;383(8):721-732. doi: 10.1056/NEJMoa2003697.

    PMID: 32813948BACKGROUND
  • van Vliet S, Koh HE, Patterson BW, Yoshino M, LaForest R, Gropler RJ, Klein S, Mittendorfer B. Obesity Is Associated With Increased Basal and Postprandial beta-Cell Insulin Secretion Even in the Absence of Insulin Resistance. Diabetes. 2020 Oct;69(10):2112-2119. doi: 10.2337/db20-0377. Epub 2020 Jul 10.

MeSH Terms

Conditions

ObesityDiabetes Mellitus, Type 2Weight Loss

Interventions

Caloric Restriction

Condition Hierarchy (Ancestors)

OverweightOvernutritionNutrition DisordersNutritional and Metabolic DiseasesBody WeightSigns and SymptomsPathological Conditions, Signs and SymptomsDiabetes MellitusGlucose Metabolism DisordersMetabolic DiseasesEndocrine System DiseasesBody Weight Changes

Intervention Hierarchy (Ancestors)

Diet TherapyNutrition TherapyTherapeuticsEnergy IntakeDietNutritional Physiological PhenomenaDiet, Food, and NutritionPhysiological Phenomena

Study Officials

  • Samuel Klein, MD

    Washington University School of Medicine

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NON RANDOMIZED
Masking
NONE
Purpose
BASIC SCIENCE
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

July 31, 2014

First Posted

August 4, 2014

Study Start

August 1, 2014

Primary Completion

March 1, 2019

Study Completion

March 1, 2019

Last Updated

July 20, 2025

Record last verified: 2025-07

Data Sharing

IPD Sharing
Will not share

Locations