Testagen (Lys-Glu-Asp-Gly) is a synthetic tetrapeptide from the Khavinson bioregulatory peptide program. It is classified as a testicular bioregulator with preclinical studies examining its effects on reproductive tissue. Published research appears exclusively in Russian-language sources.

📖 Read the full Testagen research overview →

Evidence Tier: Tier 4 — Preclinical Only · Peptidings Verdict: Thin Ice