Retatrutide vs MGF (Mechano Growth Factor)
Side-by-side comparison of key properties, dosing, and research.
GLP-1 / Weight Loss Agonists
RetatrutideAnabolic & IGF
MGF (Mechano Growth Factor)- Summary
- Retatrutide is an investigational triple receptor agonist targeting GLP-1, GIP, and glucagon receptors simultaneously. Phase 2 trials showed an unprecedented average 24% body weight reduction at 48 weeks — exceeding any approved medication to date. It is in Phase 3 trials as of 2024.
- MGF (Mechano Growth Factor) is a splice variant of IGF-1 that is locally produced in muscle tissue in response to mechanical damage from exercise. It activates muscle satellite cells (stem cells) to proliferate and repair damaged fibers, making it specifically targeted at exercise-induced hypertrophy.
- Half-Life
- ~10–12 days
- Native MGF: minutes. PEG-MGF: ~3 days
- Admin Route
- SubQ
- SubQ, IM
- Research
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- Typical Dose
- 0.5 mg → 1 mg → 2 mg → 4 mg → 8 mg → 12 mg
- 200–400 mcg
- Frequency
- Once weekly
- 1–2 times per week
- Key Benefits
- ~24% body weight reduction at 48 weeks in Phase 2 (highest dose)
- Superior to both semaglutide and tirzepatide in early trial comparisons
- Triple receptor mechanism addresses multiple obesity pathways
- Significant reduction in liver fat (MASH/NAFLD indication being studied)
- Improved cardiovascular and metabolic markers
- Once-weekly dosing
- Potential for greatest weight loss of any currently investigated compound
- Activates muscle satellite cells for repair and growth
- Accelerates recovery from muscle damage
- Synergistic with IGF-1 LR3 (different mechanisms)
- Promotes muscle hypertrophy specifically at exercised muscles
- Faster recovery between training sessions
- Potential for injury repair in connective tissue
- Side Effects
- Nausea and vomiting (common during titration, similar to semaglutide/tirzepatide)
- Diarrhea
- Constipation
- Heart rate increase (from glucagon receptor agonism)
- +2 more
- Muscle soreness (satellite cell activation)
- Injection site irritation
- Hypoglycemia risk (modest, less than IGF-1 LR3)
- Stacks With
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