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ToolsComparePEG-MGF vs Thymalin

PEG-MGF vs Thymalin

Side-by-side comparison of key properties, dosing, and research.

Anabolic & IGF
PEG-MGF
Immune SupportAnti-Aging & Longevity
Thymalin
Summary
PEG-MGF (Pegylated Mechano Growth Factor) is a modified form of MGF (Mechano Growth Factor) where polyethylene glycol (PEG) chains have been attached to extend its half-life from minutes to days. Native MGF is released locally in muscle in response to mechanical stress and quickly degrades. PEGylation allows systemic administration with sustained circulation, enabling whole-body muscle repair and anabolic signaling rather than the purely local effect of native MGF.
Thymalin is a polypeptide complex isolated from calf thymus glands (developed by the Russian Gerontology Institute), shown to restore immune function, extend lifespan, and reverse thymic involution. Clinical studies demonstrate improved immune parameters and up to 40% reduction in mortality in elderly patients.
Half-Life
~3 days (due to PEGylation)
Not well characterized as a complex extract; individual peptides have varying kinetics
Admin Route
SubQ
SubQ, IM
Research
Typical Dose
200–400 mcg
10 mg IM or SC daily
Frequency
2–3x per week
Once daily
Key Benefits
  • Extended half-life (~3 days) vs native MGF (minutes)
  • Systemic muscle satellite cell activation via subcutaneous injection
  • Promotes muscle fiber repair and hypertrophy throughout the body
  • Enhanced recovery from intense training or muscle injury
  • Synergistic with IGF-1 LR3 and growth hormone peptides
  • Useful in sarcopenia, post-injury recovery, and athletic performance
  • Single injection provides multi-day anabolic signaling
  • Restores thymic function and T-cell immunity
  • Extends healthy lifespan (documented in long-term studies)
  • Reduces infectious disease incidence in elderly
  • Normalizes immune parameters in immunodeficiency
  • Anti-tumor immune surveillance
  • Improves vaccine response in elderly
  • Reduces cardiovascular mortality (40% in landmark Russian study)
  • Normalizes neuroendocrine function
Side Effects
  • Water retention and localized swelling
  • Potential hypoglycemia at high doses
  • Theoretical cancer growth risk (growth factor)
  • Injection site reactions
  • +1 more
  • Very well tolerated in decades of Russian clinical use
  • Mild injection site reactions
  • Rare: mild allergic reaction (natural extract)
  • Transient flu-like symptoms on initiation (immune activation)
Stacks With