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ToolsCompareTestagen vs PNC-27

Testagen vs PNC-27

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

Anti-Aging & Longevity
Testagen
Immune Support
PNC-27
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.
PNC-27 is a synthetic peptide derived from the p53 tumor suppressor protein, containing both an HDM2-binding domain and a transmembrane penetratin sequence. It selectively kills cancer cells by binding MDM2/HDM2 overexpressed on the plasma membrane of malignant cells, inducing membranolysis without harming normal cells.
Half-Life
Short (minutes); sustained gene-regulatory effects
Not well established; estimated minutes to hours
Admin Route
SubQ, Oral
Intravenous (research), Intraperitoneal (research)
Research
Typical Dose
10 mg per day
Not established for humans; research doses vary by cell line and model
Frequency
Daily for 10–30 days
Not established for human use
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 cytotoxicity against cancer cells overexpressing HDM2/MDM2
  • Spares normal cells lacking surface HDM2 expression
  • Membranolytic mechanism bypasses intracellular resistance pathways
  • Demonstrated activity against breast, pancreatic, leukemia, and melanoma cell lines
  • Potential for combination with conventional chemotherapy
  • Novel non-genotoxic anticancer mechanism
Side Effects
  • Generally well tolerated
  • Mild injection site reactions
  • No significant endocrine disruption reported at standard doses
  • Limited human clinical data; largely in vitro and animal studies
  • Potential immunogenic reactions (foreign peptide)
  • Systemic toxicity at high doses not well characterized
  • Unknown interactions with current chemotherapy agents
Stacks With