Endoluten

An oral capsule preparation of bovine pineal peptide extract from the Khavinson bioregulator program, marketed as the A-8 counterpart to injectable Epithalamin and distinct from the synthetic tetrapeptide epitalon.

Also referenced as: Endoluten A-8, A-8 Endoluten, Cytomax Endoluten, Endoluten Lingual, A-8 peptide bioregulator

Also appears in: Longevity

What is Endoluten?

Endoluten is not a single defined peptide. It is a low-molecular-weight peptide fraction extracted from bovine pineal tissue, sold in oral capsules under the trade designation A-8 within the “cytomax” line of natural-extract bioregulators associated with Vladimir Khavinson and the Saint Petersburg Institute of Bioregulation and Gerontology. Because it is an extract rather than a synthesized molecule, its contents are defined by a manufacturing process and a molecular-weight cutoff rather than by a sequence, which is the central difference between it and the synthetic compounds it is marketed alongside.

It appears in the research-peptide market as the convenient oral member of a three-part pineal family whose names are used almost interchangeably by sellers, and most of the evidence invoked for it was generated on the other two.

How it works

No mechanistic study has been published on the capsule preparation itself. The mechanisms below belong to Epithalamin, the injectable pineal extract, and to epitalon, the synthetic tetrapeptide derived from it:

• Melatonin-axis modulation — in elderly subjects, a course of Epithalamin raised nocturnal plasma melatonin in those whose pineal output was low at baseline, but melatonin tended to decrease in subjects whose pineal function was already normal; the authors described the effect as modulating rather than uniformly increasing (Korkushko et al., Bulletin of Experimental Biology and Medicine, 2004, 137(4):389–391). In animals, Epithalamin was reported to increase melatonin synthesis and secretion in rats (Anisimov et al., Mechanisms of Ageing and Development, 1998, 103(2):123–132), the same axis examined in an earlier study of pineal and serum melatonin in old rats (Anisimov et al., Annals of the New York Academy of Sciences, 1992, 673:53–57), and epitalon raised basal night melatonin in old rhesus monkeys while leaving young animals unchanged (Goncharova et al., Experimental Gerontology, 2005, 40(1–2):51–57)
• Antioxidant activity — Epithalamin was reported to inhibit free-radical processes in rodents, in Drosophila, and in patients with age-related pathology, and the authors of the lifespan work suggested that these antioxidative properties were what produced the survival effects they observed; they did not attribute those effects to a telomere mechanism (Anisimov et al., Mechanisms of Ageing and Development, 1998, 103(2):123–132; Anisimov et al., Neuroendocrinology Letters, 2001, 22(1):9–18)
• Short-peptide gene regulation — the Khavinson group’s general model holds that short peptides cross the cell and nuclear membranes and regulate transcription epigenetically, interacting with histones and DNA directly; AEDG is one of the peptides they place in this scheme (Khavinson et al., Stem Cell Reviews and Reports, 2020, 16(1):118–125). This is the group’s own framework and has not been independently confirmed for these preparations
• Telomerase induction — belongs to the synthetic peptide, in cell culture — adding epitalon to telomerase-negative human fetal fibroblasts induced expression of the catalytic subunit, telomerase activity, and telomere elongation (Khavinson et al., Bulletin of Experimental Biology and Medicine, 2003, 135(6):590–592). This was the synthetic tetrapeptide applied directly to cultured cells, not an extract, not oral, and not in a living organism

Research status

A PubMed search for “Endoluten” returns zero records as of August 2026, while “Epithalamin” returns over a hundred, and ClinicalTrials.gov lists no registered study of Endoluten, Epithalamin, or epitalon. The capsule has no research record of its own; what follows is the parent literature.

Epithalamin (the injectable extract) carries the human data:

• Khavinson and Morozov (2003) reported on 266 elderly persons followed 6–8 years, with the peptides given during the first 2–3 years. Mortality fell 1.6–1.8-fold in the Epithalamin group and 2.5-fold with Thymalin plus Epithalamin. A further subgroup given Thymalin in combination with Epithalamin annually for six years showed a 4.1-fold reduction — the largest figure on the page belongs to the two-preparation combination, not to the pineal preparation alone (Neuroendocrinology Letters, 24(3–4):233–240)
• Korkushko et al. (2006) reported a 12-year randomized study in elderly coronary patients with accelerated cardiovascular aging: 28% lower all-cause mortality and roughly halved cardiovascular mortality versus the same basic therapy alone (Bulletin of Experimental Biology and Medicine, 142(3):356–359)
• Korkushko et al. (2011) reported the 15-year follow-up — 39 coronary patients given six courses of epithalamin over three years alongside basic therapy, against 40 controls on basic therapy alone — describing decelerated cardiovascular aging, normalized melatonin rhythm, and lower mortality (Bulletin of Experimental Biology and Medicine, 151(3):366–369). This shares its author team, institute, design, and patient group with the 2006 report: the two are almost certainly one cohort described at two follow-up points, not two independent trials, and should not be counted as separate replications. The indexed English title of the 2011 paper says “pituitary gland,” but the abstract describes epithalamin and closes by naming the pineal gland; the title appears to be a translation error

Animal work predates the clinical reports. Anisimov et al. (1998) reported mean lifespan increases of 11–31% across Drosophila, two mouse strains, and rats, though the effect was not uniform — maximum lifespan rose in the flies, C3H/Sn mice and rats, while mortality rate was unchanged in SHR mice (Mechanisms of Ageing and Development, 103(2):123–132). The group summarized two decades of gerontology and oncology work on the preparation in Annals of the New York Academy of Sciences (1994, 719:483–493), and Khavinson’s book-length survey of the wider program ran as a journal supplement (Neuroendocrinology Letters, 2002, 23 Suppl 3:11–144).

Several limitations apply to all of it. The Korkushko reports are described as randomized, but no available abstract describes blinding or placebo control — the comparators received basic therapy alone — and the 2003 follow-up does not describe randomization at all. Authorship traces to a single collaborating network in Saint Petersburg and Kiev, most of the corpus appeared in Russian-language journals, and no group outside that network has replicated the mortality findings. A mortality reduction of the size reported would be a major result in geriatric medicine, and it has not been tested in a registered trial in the roughly two decades since publication. A 2025 review from an independent Polish group surveyed the epitalon literature and, while crediting a range of demonstrated effects, noted that it remains uncertain whether those are its only mechanisms and that its physico-chemical and structural characterization is sparse (Araj et al., International Journal of Molecular Sciences, 26(6):2691). Separately, a registered Russian injectable pineal polypeptide complex marketed as Pineamin was reported to raise nocturnal 6-sulfatoxymelatonin excretion 1.9-fold in 55 elderly patients — but those patients were selected for already-diminished pineal melatonin output, the comparison is against their own pre-treatment values rather than an untreated control group, and one co-author is affiliated with the manufacturer (Trofimova et al., Advances in Gerontology, 2017, 30(3):422–426). Again an injectable, and again from the same institute.

Common dosage forms

Endoluten is sold as oral capsules, commonly listing on the order of 10 mg of pineal peptide complex per capsule, and in sublingual liquid or “lingual” presentations. This differs from both relatives it is confused with: Epithalamin was a Russian pharmacopoeia preparation given by injection, and epitalon is sold in the research market as a lyophilized powder in vials for reconstitution. Vendors frequently list all three under overlapping names, and combination packs pairing the pineal extract with thymic or other tissue extracts are common. No Endoluten product is FDA-approved, and there is no licensed US compounding route for it. This section describes formats only and is not dosing guidance.

Key considerations

• Three different things share one set of names. Epithalamin is a bovine pineal extract given by injection; epitalon (AEDG, Ala-Glu-Asp-Gly) is a synthetic tetrapeptide whose sequence was chosen from the amino acid composition of that extract (Araj et al., International Journal of Molecular Sciences, 2025); Endoluten is an oral capsule of pineal extract. Evidence generated on one is routinely presented as evidence for another. The telomere and telomerase claims in particular come from the synthetic peptide in cell culture, and the mortality claims come from the injectable extract. Because these are three distinct preparations, a vendor listing for injectable Epithalamin is not a listing for this product.
• The melatonin claim is narrower than it is usually stated. The primary human finding is bidirectional: melatonin rose in subjects with low baseline pineal output and tended to fall in those with normal output (Korkushko et al., 2004) — a small pre/post study whose abstract reports neither a sample size nor a control group. “Restores melatonin” is a defensible reading only for the low-baseline subgroup; “increases melatonin” as a general statement is not what the study reported.
• Bovine brain-derived material carries a specific US regulatory frame. The pineal gland sits within the brain. Under 21 CFR 189.5(b)(1), no human food — a category that includes dietary supplements — may be manufactured from, processed with, or otherwise contain prohibited cattle materials, which comprise specified risk materials (the brain, skull, eyes, trigeminal ganglia, spinal cord, vertebral column and dorsal root ganglia of cattle 30 months of age and older) and, separately and at any age, material from cattle not inspected and passed. Sellers describe the source as young calves, which would sit outside the 30-month specified-risk-material threshold — but that alone does not clear the rule, because the inspected-and-passed and designated-country conditions apply at any age. The dietary-ingredient language in the section is a food-additive carve-out at (d)(3): it exempts such material from section 409 food-additive review, not from the (b)(1) prohibition or the adulteration provisions at (d)(1)–(2). Sourcing documentation and the inspection status of the source herd are the material questions for any bovine brain-derived preparation entering the US.
• Oral administration of a peptide extract has never been characterized. There is no published pharmacokinetic, absorption, or bioavailability study for the capsule form. Whether a peptide fraction survives gastric and intestinal proteolysis intact and in what quantity is unknown, and the entire human evidence base was generated by injection — the route that bypasses the question.
• No regulatory approval anywhere in the West. The preparation is not approved by FDA or EMA and is not an FDA-approved anti-aging medicine. It reaches US buyers as a supplement or research item, and its contents are not verified by any approval process.