Livagen

Livagen is a synthetic tetrapeptide with the verified sequence Lys-Glu-Asp-Ala (KEDA), developed by Vladimir Khavinson and colleagues at the St. Petersburg Institute of Bioregulation and Gerontology as a synthetic analog of the natural liver polypeptide complex Ventvil. The compound is documented in approximately 15 PubMed-indexed papers across two collaborating research networks (Khavinson institute in St. Petersburg; Lezhava and Dzhokhadze group in Tbilisi). The most-cited mechanism (PMID 12533768, Bull Exp Biol Med 2002) is epigenetic chromatin remodeling: ex vivo treatment of lymphocytes from elderly donors induced decondensation of pericentromeric structural heterochromatin and reactivated age-silenced ribosomal RNA genes. Additional documented activities include enkephalinase inhibition in human serum (IC50 ~20 micromolar, PMID 12942748), age-normalization of digestive enzyme activity in rats given oral KEDA (PMID 16075683), and hepatocyte protein synthesis enhancement in cultured rat liver cells (PMID 15926314). A 2020 Khavinson-group review (PMID 32362099) synthesizes animal hepatitis and cirrhosis model data. No randomized controlled trial, no human pharmacokinetic study, and no fully independent (non-Khavinson-network) Western replication has been published. IMPORTANT SEQUENCE CORRECTION: Livagen is KEDA, not KEDG. KEDG is the sequence for Testagen, a different Khavinson peptide. Vendors and biohacking sources occasionally cite the wrong sequence.

• Chromatin Reactivation (ex vivo)
• Hepatocyte Protein Synthesis (preclinical)
• Hepatitis / Cirrhosis (review-only)

Proposed chromatin remodeler with ex vivo evidence for de-heterochromatinization in aged lymphocytes and rat hepatocyte protein synthesis enhancement

Synthetic tetrapeptide Lys-Glu-Asp-Ala. Ex vivo evidence indicates pericentromeric structural heterochromatin decondensation and reactivation of age-silenced ribosomal RNA genes in elderly lymphocytes. In vitro evidence shows enkephalinase inhibition in human serum (IC50 ~20 micromolar) without direct opioid receptor binding. In cultured rat hepatocytes, Livagen increased protein synthesis amplitude with the largest effect in old animals. No molecular receptor target has been identified at structural resolution.

Peak plasma concentration: 3 min. Elimination half-life: 30 min. Largely cleared by: ~2.5 hrs.

The typical cycle length for Livagen is 2 weeks (rat oral protocol). Community injectable cycles run 10-20 days without published validation.. Recommended break between cycles: Khavinson protocol framework references quarterly cycles; no published evidence-based interval..

• Testagen — Use Caution: Testagen has the sequence Lys-Glu-Asp-Gly (KEDG) and is a gonadal bioregulator. Livagen has the sequence Lys-Glu-Asp-Ala (KEDA). The two are routinely confused because of the shared KED prefix. Verify the COA before use; sourcing the wrong compound delivers Testagen activity instead of Livagen.
• Epitalon — Synergistic: Both are short Khavinson bioregulators with chromatin-level effects. The 2002 foundational Bull Exp Biol Med paper (PMID 12533768) and follow-up Lezhava studies compared Livagen and Epitalon and found both produced pericentromeric heterochromatin decondensation in elderly lymphocytes, with overlapping but distinct chromosome targets. Co-administration is part of the Khavinson protocol framework.
• Vilon — Compatible: Vilon (Lys-Glu, KE) shares two amino acids with Livagen and overlapping chromatin effects in the same ex vivo lymphocyte model. Co-administration is common in Khavinson short-peptide protocols. No documented adverse interaction.
• Cortagen — Compatible: Cortagen is another Khavinson short peptide tested in the same ex vivo lymphocyte chromatin model (PMID 15085253, 37042594). Mechanistically overlapping but tissue-specific differences. No documented adverse interaction.
• Opioids and enkephalinase inhibitors — Monitor Combination: Livagen inhibits enkephalin-degrading enzymes in human serum in vitro (IC50 ~20 micromolar, PMID 12942748). The physiological significance of this finding at achievable in vivo concentrations is uncharacterized, but combining Livagen with opioid analgesics or other peptidase-inhibiting drugs is theoretically not innocuous.
• Immunosuppressants — Unknown: No published interaction data. Mechanism is local epigenetic regulation, not systemic immunomodulation, so interaction is theoretically minimal but not characterized.
• Hepatotoxic medications — Unknown: The Khavinson group proposes Livagen as hepatoprotective based on a 2020 narrative review (PMID 32362099) of animal hepatitis and cirrhosis models. Whether this translates to protection against hepatotoxic drug therapy (acetaminophen overdose, methotrexate, etc.) in humans has not been studied. Do not rely on Livagen for hepatic risk mitigation in real clinical drug use.
• Cancer chemotherapy — Avoid Combination: Livagen has been tested ex vivo in breast cancer patient lymphocytes (PMID 28574395) for chromosomal protection. Use in active oncology has not been studied in vivo, and the chromatin-deheterochromatinization mechanism could theoretically interact unpredictably with cytotoxic therapy.

Supplies:

• Livagen lyophilized powder
• 0.9% sterile sodium chloride or bacteriostatic water
• Insulin syringes (29-31 gauge)
• Alcohol prep pads

1. 1Store lyophilized vial at 2-8°C until use
2. 2Allow vial to reach room temperature for 5-10 minutes
3. 3Add solvent slowly down the vial wall; do not shake
4. 4Gently swirl until fully dissolved (solution should be clear)
5. 5Reconstitution volume is operator-dependent because no human dose has been published; common community practice is 1-2 mL per 10 mg vial
6. 6Use reconstituted solution within 7-10 days; store at 2-8°C between uses

No published human pharmacokinetic data and no published human efficacy timeline.. Ex vivo lymphocyte chromatin shifts occur within 24-72 hours of cell exposure.. Rat oral digestive-enzyme normalization observed over a 2-week dosing course.. Hepatocyte protein synthesis enhancement is amplitude-based, not threshold-based, in the published rat cell-culture model..

No structured Phase I safety study has been published. The 15-paper PubMed footprint is overwhelmingly ex vivo lymphocyte and rat hepatocyte work with no formal AE reporting; absence of reported events does not equal demonstrated safety.. As a tetrapeptide of naturally occurring L-amino acids, acute systemic toxicity is expected to be low on class grounds, but this is inference, not data.. The enkephalinase-inhibition mechanism (in vitro IC50 ~20 micromolar, PMID 12942748) is theoretically capable of altering endogenous opioid tone; clinical significance has not been studied. Treat the opioid interaction line on this page as directional logic.. Pregnancy, lactation, renal/hepatic impairment, and pediatric use have not been studied; default to non-use in these populations.. Russian-language source publications often omit dose, route, and AE detail from the available English abstracts; full text review may reveal more.. Not FDA approved, not EMA approved, no verified Russian pharmaceutical drug registration. Sold internationally as a research chemical..

No structured Phase I safety study has been published. The 15-paper PubMed footprint is overwhelmingly ex vivo lymphocyte and rat hepatocyte work with no formal AE reporting; absence of reported events does not equal demonstrated safety.. As a tetrapeptide of naturally occurring L-amino acids, acute systemic toxicity is expected to be low on class grounds, but this is inference, not data.. The enkephalinase-inhibition mechanism (in vitro IC50 ~20 micromolar, PMID 12942748) is theoretically capable of altering endogenous opioid tone; clinical significance has not been studied. Treat the opioid interaction line on this page as directional logic.. Pregnancy, lactation, renal/hepatic impairment, and pediatric use have not been studied; default to non-use in these populations.. Russian-language source publications often omit dose, route, and AE detail from the available English abstracts; full text review may reveal more.. Not FDA approved, not EMA approved, no verified Russian pharmaceutical drug registration. Sold internationally as a research chemical..

Livagen should be stored at Lyophilized: 2-8°C. Reconstituted: 2-8°C, use within 7-10 days..