Livagen (KEDA): Evidence, Mechanism & Legal Status

Livagen is a synthetic tetrapeptide from Vladimir Khavinson's St. Petersburg "peptide bioregulator" program, proposed as a liver- and immune-targeted geroprotector that acts epigenetically by decondensing age-condensed chromatin and reactivating silenced genes.1 Its longevity marketing is enthusiastic; its human evidence is absent. This monograph separates the two.

This article is informational and editorial content for research and educational purposes only. It is not medical advice, not a protocol to follow, and not a sourcing guide. Livagen is not an FDA-approved drug; it is sold as a "research chemical not for human use." Dosing figures are reported strictly as seen in the published literature for completeness — not as recommendations. Consult a licensed clinician before any health decision.

What is Livagen and how is it supposed to work?

Livagen is a synthetic tetrapeptide with the sequence Lys-Glu-Asp-Ala (KEDA), molecular formula C18H31N5O9, MW approximately 461.5 g/mol.11 It was developed by Khavinson and colleagues at the St. Petersburg Institute of Bioregulation and Gerontology as the "active core" tetrapeptide derived from a calf-liver polypeptide complex (Ventvil), within the same class of short peptide bioregulators as Epitalon (AEDG), Vilon (KE) and Thymogen (EW).4 The CAS numbers vendors cite (e.g., 195875-84-4) vary across sources and were not independently confirmable in a primary registry during this review — treat them as unverified.

The proposed mechanism — all of it preclinical — is an epigenetic, chromatin-decondensation model. The class hypothesis is that very short peptides penetrate the cell and nucleus and bind DNA or histone regions in a sequence-selective way, loosening heterochromatin and de-repressing genes that become epigenetically silenced with age.1 In cultured lymphocytes from elderly donors, Livagen reportedly produced activation of ribosomal genes, decondensation of pericentromeric structural (C-) heterochromatin, and release of euchromatic genes repressed by age-related condensation — what the authors termed "de-heterochromatinization" of chromatin, reported specifically at heterochromatin-rich chromosomes 1, 9 and 16.1 A follow-up reported that Livagen shifts cobalt-induced sister-chromatid exchange in aged lymphocytes from pericentromeric toward telomeric heterochromatin.3 The central caveat: the model that a four-residue peptide can produce tissue-selective, gene-specific transcriptional effects is mechanistically debated and rests largely on the originating group's binding work without broad independent structural confirmation.13

What is the evidence by indication?

The framing matters more than any single result: there are no human randomized controlled trials of Livagen, no registered clinical trials, and no replication outside the Khavinson group. The human chromatin work used donor cells in culture — human-tissue mechanistic data, not a clinical efficacy trial. Every indication below is therefore capped at C (preclinical) or D (claim-only). For context, the U.S. National Library of Medicine registry at ClinicalTrials.gov returns no interventional Livagen study, underscoring how early-stage this compound remains.

The chromatin work is the most cited and the most extrapolated. In cultured lymphocytes from elderly donors — a related study used 80-to-91-year-olds versus 18-to-30-year-old controls — Livagen activated ribosomal genes and decondensed pericentromeric heterochromatin.1 These are qualitative cytogenetic and biophysical observations, not clinical endpoints, with small unreplicated samples, and there is no evidence the effects translate to any aging-related health outcome in living humans.3 The liver story comes from a 2020 review reporting that both the calf-liver complex (Ventvil) and the KEDA tetrapeptide showed "high efficiency" in rodent models of fibrosis and acute and chronic hepatitis — restoring liver function and normalizing immune and antioxidant status, with maximal effect in aging animals.4 Secondary summaries describe normalized bilirubin, cholesterol and ALT/AST and roughly 15 to 16 percent increased explant growth in aged-rat liver cultures.12 All of it is animal or in-vitro; no human hepatology trial exists.

What doses appear in the literature?

Reported strictly as information, not a protocol. No human dose has been validated for safety or efficacy, and there is no peer-reviewed human dose, route, frequency or course for Livagen.1 The mechanistic studies used nanomolar concentrations applied directly to cultured cells such as lymphocytes and hepatocytes — these are in-vitro exposures, not body doses, and cannot be translated into a human regimen.1 Vendors sell lyophilized powder in research vials (commonly around 20 mg) labeled "research use only / not for human consumption," typically with instructions to reconstitute in bacteriostatic water and store refrigerated — laboratory handling notes, not human dosing.11 As an unprotected tetrapeptide, Livagen is expected to have a very short plasma half-life (minutes-order) and to be degraded by gastrointestinal and plasma peptidases, making oral bioavailability low and unreliable; any pharmacokinetic statement for Livagen specifically is inferential, not measured.13

How safe is Livagen, and what is its 2026 legal status?

There is no controlled human safety data — no systematic adverse-event profile, no human toxicology, and no drug-interaction studies. The absence of reported harms reflects the absence of human study, not a clean record. The Khavinson program describes short bioregulator peptides as low-toxicity in animals, but that is animal-model and expert-opinion grade and does not establish human safety.4 From a functional and integrative, precautionary view, the dominant theoretical concern is mechanistic: a peptide whose proposed action is to de-repress silenced genes and stimulate protein synthesis and tissue growth warrants caution in anyone with active or suspected malignancy, because reactivating growth programs is theoretically double-edged.1 Research-grade peptides also carry impurity, endotoxin, immunogenicity and sterility hazards — the same concerns FDA cited when restricting unapproved peptides from compounding.6 Pregnancy, lactation, pediatric use, active cancer and immunosuppression are precautionary contraindications.

Legally, Livagen is not FDA-approved for any indication and has no USP monograph. It is not a component of an approved drug and does not appear on the FDA 503A or 503B bulk drug substance lists, so it cannot lawfully be used in pharmacy compounding.6 Crucially, unlike better-known peptides, Livagen was never individually named in the 2023-to-2026 FDA Category-2 peptide actions — the agency moved a set of popular peptides into Category 2 in September 2023, removed five in September 2024 after nomination withdrawals, and in April 2026 announced intent to remove twelve more pending PCAC review, but Livagen sits entirely outside that nomination and compounding framework as a pure "research use only" substance.78 Research-use-only labeling confers no legal cover if a product is marketed or used for human consumption, and FDA and state attorneys general have pursued enforcement where human use is implied.9 For athletes, Livagen is not individually listed on the WADA Prohibited List, but as a non-approved synthetic agent it could be captured by the S0 "Non-Approved Substances" clause, which prohibits such substances in sport at all times — treat it as high-risk and verify against the current List.10 It is not a DEA-controlled substance.

Bottom line. Livagen pairs an intellectually interesting epigenetic hypothesis with a near-total absence of human proof. What is actually studied is human lymphocytes and rat hepatocytes in vitro plus rodent hepatitis and fibrosis models; what is proven in humans is nothing — graded C, drifting to D for any longevity claim, single-lab and unreplicated. From a measured functional-medicine view the liver and immune-resilience direction is worth honest investigation, but the marketing far outruns the evidence. Regulatory facts here are current as of June 2026 and should be re-verified after any subsequent FDA peptide actions.