Brown Adipose Tissue as a Mechanistic Determinant of Semaglutide Treatment Response in Obesity (BAT-Sema Study)

NCT07621640 | Not Yet Recruiting

• 2 other identifiers: 2026-04-009RS-2026-25483260
• Study Type: interventional
• Target: 80
• Locations: 1 country
• Sites: 2

Brief Summary

This study investigates whether the activity of brown adipose tissue (BAT) - a special type of fat that burns energy as heat - can predict how well individuals with obesity respond to semaglutide (Wegovy), a once-weekly injectable weight loss medication. Participants who are starting semaglutide treatment will undergo ¹⁸FDG-PET/CT imaging before and after 24 weeks of treatment. Prior to each PET/CT scan, participants will wear a water-circulating cooling vest to activate BAT. By measuring BAT activity at baseline and comparing it with the degree of weight loss and metabolic improvement at 24 weeks, the investigators aim to identify BAT as a predictive biomarker for personalized obesity treatment.

Conditions

Obesity; Metabolic Syndrome; Brown Adipose Tissue

Keywords

Brown adipose tissue; Semaglutide; GLP-1 receptor agonist; Obesity; FDG-PET/CT; BAT; Biomarker; Weight loss; PDFF

Outcome Measures

Primary Outcomes (1)

• Correlation between baseline BAT metabolic activity (SUVmean and BAT volume on ¹⁸FDG-PET/CT) and percentage body weight loss at 24 weeks of semaglutide treatment

  : Pearson (or Spearman) correlation coefficient between baseline BAT parameters (SUVmean, BAT volume, total metabolic activity per BARCIST 1.0) and % body weight loss after 24 weeks of semaglutide therapy (0.25 mg escalated to 2.4 mg).

  Baseline to 24 weeks

Secondary Outcomes (17)

• Change in waist circumference

  Baseline to 24 weeks

• Change in body weight (kg)

  Baseline to 24 weeks

• Change in Body Mass Index (BMI)

  Baseline to 24 weeks

• Change in HbA1c (%)

  Baseline to 24 weeks

• Change in fasting glucose (mg/dL)

  Baseline to 24 weeks

Study Arms (1)

Semaglutide + BAT Evaluation

EXPERIMENTAL

Adults with obesity initiating semaglutide (0.25 mg → 2.4 mg over 20 weeks, maintained for 4 weeks; total 24 weeks). At baseline and 24 weeks, ¹⁸FDG-PET/CT with individualized cold stimulation (water-circulating cooling vest at 16°C, 60 minutes) and liver MRI (PDFF + MRE) are performed.

Drug: Semaglutide (Wegovy®); Procedure: ¹⁸FDG-PET/CT with cold stimulation; Procedure: Liver MRI (PDFF + MRE)

Interventions

Semaglutide (Wegovy®) DRUG

Once-weekly subcutaneous injection, titrated from 0.25 mg to 2.4 mg over 20 weeks per standard protocol. Standard of care treatment for obesity.

Semaglutide + BAT Evaluation

¹⁸FDG-PET/CT with cold stimulation PROCEDURE

Whole-body ¹⁸FDG-PET/CT (5.18 MBq/kg, max 370 MBq) after 60-minute individualized cold stimulation using a water-circulating cooling vest (Polar Products Arctic Chiller, starting 16°C). Performed at baseline (V1) and 24 weeks (V7). BAT activity quantified per BARCIST 1.0.

Semaglutide + BAT Evaluation

Liver MRI (PDFF + MRE) PROCEDURE

Hepatic proton density fat fraction (MRI-PDFF) and liver stiffness by MR elastography (MRE) using Siemens MAGNETOM Vida 3T. Performed at baseline (V1) and 24 weeks (V7).

Semaglutide + BAT Evaluation

Eligibility Criteria

• Age: 20 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 20-70 years at the time of enrollment
• Initiating semaglutide (Wegovy) treatment for obesity (newly starting treatment)
• BMI ≥ 27 kg/m² with at least one weight-related comorbidity:
• Hypertension (SBP ≥130 or DBP ≥80 mmHg, or on antihypertensive medication)
• Dyslipidemia (LDL-C ≥130, TG ≥150, or low HDL-C, or on lipid-lowering medication)
• Non-alcoholic fatty liver disease (NAFLD/MASLD, confirmed by imaging or ALT/AST ≥1.5× ULN)
• Obstructive sleep apnea (AHI ≥5/hr or clinically diagnosed)
• Established cardiovascular disease (CAD, stroke, PAD)
• Obesity-related osteoarthritis of knee or hip with functional impairment OR BMI ≥ 30 kg/m² (regardless of comorbidity)
• Ability and willingness to provide written informed consent

You may not qualify if:

• Diagnosis of type 1 or type 2 diabetes mellitus
• History of neck surgery or radiation therapy to the neck
• Use of anti-obesity medications within 1 month prior to enrollment, or current use of beta-adrenergic blocking agents
• Personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia type 2 (MEN2)
• Active malignancy, severe renal disease (eGFR \<30 mL/min/1.73m²), severe hepatic disease, or other severe endocrine disorders
• Pregnancy or breastfeeding
• Severe psychiatric illness or cognitive impairment precluding informed consent
• Contraindication to MRI (pacemaker, cochlear implant, non-MRI-compatible implants)
• Severe claustrophobia

Sponsors & Collaborators

• Hallym University: lead
• Hallym University Dongtan Sacred Heart Hospital: collaborator

Study Sites (2)

Hallym University Dongtan Sacred Heart Hospital

Hwaseong-si, Gyeonggi-do, 18450, South Korea

Location

Seoul National University Bundang Hospital

Seongnam-si, Gyeonggi-do, 13620, South Korea

Location

MeSH Terms

Conditions

Obesity; Metabolic Syndrome; Weight Loss

Interventions

semaglutide

Condition Hierarchy (Ancestors)

Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Insulin Resistance; Hyperinsulinism; Glucose Metabolism Disorders; Metabolic Diseases; Body Weight Changes

Central Study Contacts

Hun Jee Choe Hallym University Dongtan Sacred Heart Hospital, MD, PhD

CONTACT

+82-31-8086-2869; hunjeechoe@gmail.com

Hye Jeong Lee Hallym University Dongtan Sacred Heart Hospital, CRC

CONTACT

+82-10-4694-3886; geumzzogi@naver.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor, Division of Endocrinology and Metabolism

Model Details: Single-arm prospective mechanistic cohort study evaluating the association between baseline brown adipose tissue activity and semaglutide treatment response in adults with obesity using individualized cold-stimulated ¹⁸FDG-PET/CT.

Study Record Dates

• First Submitted: May 20, 2026
• First Posted: June 2, 2026
• Study Start: June 1, 2026
• Primary Completion (Estimated): February 1, 2028
• Study Completion (Estimated): February 1, 2031
• Last Updated: June 2, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

KR (2)