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ToolsCompareTestagen vs AOD-9604

Testagen vs AOD-9604

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

Anti-Aging & Longevity
Testagen
Fat Loss & Metabolic
AOD-9604
Summary
Testagen is a tetrapeptide bioregulator (Lys-Glu-Asp-Gly) developed by Professor Vladimir Khavinson, tissue-specific for the testes. It supports Leydig cell function, normalization of testosterone biosynthesis, and spermatogenic activity. Testagen is used in men's health protocols for age-related testosterone decline, male fertility support, and testicular anti-aging.
AOD-9604 is a modified fragment of human growth hormone (residues 177-191) with an additional tyrosine residue that significantly enhances bioavailability. Originally developed as an anti-obesity drug by Metabolic Pharmaceuticals, it stimulates lipolysis and inhibits lipogenesis without the diabetogenic effects of full GH.
Half-Life
Short (minutes); sustained gene-regulatory effects
30-45 minutes injectable; longer with nasal spray formulation
Admin Route
SubQ, Oral
SubQ, Intranasal, Oral
Research
Typical Dose
10 mg per day
300-600 mcg
Frequency
Daily for 10–30 days
Once daily
Key Benefits
  • Supports endogenous testosterone synthesis via Leydig cell normalization
  • Promotes spermatogenesis and sperm quality
  • Anti-aging effects on testicular tissue
  • May attenuate age-related testosterone decline
  • Mechanistically distinct from TRT — does not suppress HPG axis
  • Useful adjunct to Gonadorelin and Kisspeptin-10 in male hormonal protocols
  • Supports male fertility without exogenous hormone replacement
  • Selective fat loss without anabolic side effects
  • No effect on blood glucose or insulin resistance
  • Improved bioavailability over Fragment 176-191
  • GRAS (Generally Recognized As Safe) status in Australia
  • Potential cartilage repair and anti-inflammatory properties
  • Does not suppress natural GH production
Side Effects
  • Generally well tolerated
  • Mild injection site reactions
  • No significant endocrine disruption reported at standard doses
  • Localized injection site reactions
  • Headache (rare)
  • Hypoglycemia risk in combination with insulin (very rare)
Stacks With