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ToolsCompareThymalin vs Retatrutide

Thymalin vs Retatrutide

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

Immune SupportAnti-Aging & Longevity
Thymalin
GLP-1 / Weight Loss Agonists
Retatrutide
Summary
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.
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.
Half-Life
Not well characterized as a complex extract; individual peptides have varying kinetics
~10–12 days
Admin Route
SubQ, IM
SubQ
Research
Typical Dose
10 mg IM or SC daily
0.5 mg → 1 mg → 2 mg → 4 mg → 8 mg → 12 mg
Frequency
Once daily
Once weekly
Key Benefits
  • 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
  • ~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
Side Effects
  • 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)
  • Nausea and vomiting (common during titration, similar to semaglutide/tirzepatide)
  • Diarrhea
  • Constipation
  • Heart rate increase (from glucagon receptor agonism)
  • +2 more
Stacks With