Overview
This study is evaluating whether a dual glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptor agonist, tirzepatide, can affect the function, structure and metabolism of skeletal muscles in adults with obesity. Participants, premenopausal females with obesity, will receive either tirzepatide or placebo over 24 weeks. Researchers will assess body weight, body composition, muscle strength and functional performance, neuromuscular function and will perform muscle biopsies before and after treatment to study molecular and histological changes following treatment. The goal of this study is to investigate the effects of tirzepatide on skeletal muscle function, quantity, quality and metabolism in adults with obesity as well as clarify the molecular and structural adaptations in skeletal muscle during tirzepatide-induced weight loss, addressing an important gap in understanding the impact of incretin-based therapies on muscle health.
Eligibility
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