Tirzepatide effects on skeletal muscle in women with obesity

Effects of Tirzepatide on Skeletal Muscle in Obesity

Not applicable Interventional University Medical Centre Ljubljana · NCT07373834

This trial will test whether tirzepatide changes muscle strength, size, quality, and metabolism in premenopausal adult women with obesity over 24 weeks.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment30 (estimated)
Ages18 Years to 50 Years
SexFemale
SponsorUniversity Medical Centre Ljubljana Academic / other
Locations1 site (Ljubljana)
Trial IDNCT07373834 on ClinicalTrials.gov

What this trial studies

Adult premenopausal women with obesity (BMI 30–40 kg/m²) will be assigned to receive tirzepatide or matching placebo for 24 weeks. Investigators will track body weight and composition, measure muscle strength and functional performance, and evaluate neuromuscular function. Muscle biopsies taken before and after treatment will undergo molecular and histological analyses to characterize changes in muscle metabolism, fiber structure, and quality. The trial excludes participants with diabetes, sarcopenic obesity, recent obesity treatments, and other specified medical conditions.

Who should consider this trial

Good fit: Ideal candidates are premenopausal females aged 18–50 with BMI 30–40 kg/m², stable weight over the prior three months, no prior pharmacologic or surgical obesity treatments, and willing to use barrier contraception.

Not a fit: People who are postmenopausal, male, have sarcopenic obesity, diabetes, recent pancreatitis, myopathy, active malignancy, are pregnant or lactating, or are taking metformin or systemic corticosteroids are excluded and likely would not benefit from participation.

Why it matters

Potential benefit: If successful, the trial could show that tirzepatide preserves or improves muscle mass, quality, and function during weight loss, helping to reduce the risk of functional decline in women with obesity.

How similar studies have performed: GLP-1 and dual GIP/GLP-1 agonists, including tirzepatide, have produced substantial weight loss and favorable body composition changes in other trials, but direct biopsy-level effects on skeletal muscle are not well established.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Female sex
* Age between 18 and 50 years
* BMI between 30 kg/m² and 40 kg/m²
* Stable body weight within the three months preceding study enrolment (defined as ≤ 5% change)
* No prior pharmacological or surgical interventions for obesity treatment
* Commitment to use barrier contraception and absence of plans for pregnancy within 8 months following enrolment

Exclusion Criteria:

* Sarcopenic obesity
* Pregnancy or lactation
* Postmenopausal status
* Diabetes
* Immobility
* Personal history of malignancy
* Personal history of pancreatitis
* Personal history of major depressive episodes
* Personal history of myopathy
* Personal or family history of medullary thyroid carcinoma
* Current treatment with metformin or systemic corticosteroids

Where this trial is running

Ljubljana

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions ObesityTirzepatideSkeletal muscleMuscle qualityMuscle massMuscle strengthMuscle functionMyosteatosis
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.