For research and educational purposes only. Not medical advice.
There is a body of scientific work spanning more than four decades, 775 peer-reviewed publications, 196 patents, a Nobel Prize nomination, six approved pharmaceutical products, and clinical data covering over 15 million patients across Russia and Eastern Europe. It involves compounds that produced a four-fold reduction in mortality in a human cohort study. It is backed by research showing direct interaction with DNA regulatory sequences in specific organ tissues.
Most people in the Western biohacking and longevity community have never heard of it.
That is changing in 2026, and for good reason. Khavinson peptides, also called peptide bioregulators, are now among the most searched longevity compounds in the research community. Epitalon is scheduled for its first formal FDA advisory committee review on July 24, 2026. US capital is entering the space, with startups openly building on the Khavinson research foundation. The conversation that has been happening quietly in specialist circles for twenty years is finally going mainstream.
This is the most comprehensive English-language overview of Khavinson peptides available, covering who Vladimir Khavinson was, how bioregulators work at the cellular level, the complete catalog of compounds and what the research says about each, the honest assessment of where the evidence is strong and where it is not, and what the regulatory landscape looks like heading into the second half of 2026.
WHO WAS VLADIMIR KHAVINSON
Vladimir Khavinson was a Russian gerontologist, physician, and scientist who spent more than four decades studying short-chain peptides and their effects on aging, organ function, and longevity. He directed the Saint Petersburg Institute of Bioregulation and Gerontology, which became the world's foremost research center for bioregulator peptide science. He served as president of the European Association of Gerontology and Geriatrics.
His research career began in the 1970s at the Military Medical Academy in Leningrad, initially under Soviet military funding. The original application was military medicine, specifically developing tools to protect soldiers, cosmonauts, and high-performance personnel from the physiological effects of extreme stress, radiation exposure, and demanding operational conditions. What the researchers discovered, somewhat to their own surprise, was that the peptide extracts being used for stress protection also had profound effects on the aging process itself. That surprise finding became the foundation of a research program that consumed the rest of Khavinson's career.
What makes Khavinson's legacy unusual is its scope. Most scientists work on one mechanism, one disease, or one pathway. Khavinson developed an entire systematic approach to the biology of aging. He created peptide bioregulators for the pineal gland, thymus, brain, heart, blood vessels, liver, kidneys, retina, prostate, ovaries, muscles, bones, and more. Each compound was tailored to the specific DNA sequences governing the corresponding tissue. Each was taken through laboratory, animal, and human research phases.
Khavinson died on January 6, 2024, at age 77, in Saint Petersburg. His work left behind the most developed body of tissue-specific peptide longevity research in the world, still largely unknown outside Russia and Eastern Europe.
THE CENTRAL HYPOTHESIS: HOW BIOREGULATORS WORK AT THE CELLULAR LEVEL
Understanding why bioregulators are different from conventional peptides requires understanding the biological hypothesis they are built on.
Khavinson's foundational insight was that organ aging is not primarily a matter of accumulated damage, though damage certainly occurs. It is fundamentally a problem of gene expression. As tissues age, their gene expression patterns become heterochromatinized, a term describing the condensation and silencing of genetic material that was previously active. Genes responsible for tissue-specific protein production, repair signaling, and cellular maintenance are progressively silenced with age. The tissue does not lose the genetic instructions it needs to function. It loses the ability to read them.
Khavinson's hypothesis, supported by decades of experimental work, was that organ tissues produce endogenous short-chain peptides that function as local regulatory signals, essentially telling cells which genes to express. As an organism ages, production of these endogenous peptide regulators declines. Gene expression in the corresponding tissue declines in parallel. Tissue function deteriorates.
The intervention logic follows directly. If readers can identify the specific short peptide sequences involved in regulating gene expression in a given tissue, synthesize them, and administer them exogenously, they can potentially restore more youthful gene expression patterns in that tissue. Readers are not adding a drug. Readers are restoring a regulatory signal the tissue used to produce itself.
The mechanism operates at the level of histone proteins, the proteins that DNA wraps around. These histones are not static scaffolding. They are active participants in gene regulation. Chemical modifications to histones, specifically acetylation and methylation of specific sites, determine whether the DNA sections wrapped around them are accessible for transcription or silenced. Khavinson's research showed that short peptide bioregulators interact directly with histone proteins and DNA regulatory sequences, producing epigenetic changes that restore gene accessibility in aged tissue. This is not receptor-mediated pharmacology in the conventional sense. These peptides are entering cell nuclei and influencing chromatin structure directly.
This distinction from conventional peptide mechanisms is important. BPC-157 works through VEGFR2 receptor activation and downstream signaling cascades. Ipamorelin works through the ghrelin receptor on pituitary cells. These are receptor-mediated mechanisms operating at the cell surface. Bioregulators appear to work one level deeper, influencing the regulation of which genes are expressed in the first place. That is a qualitatively different mechanism and, if the research holds up to independent scrutiny, a potentially more foundational approach to the biology of aging.
CYTOMAXES VS. CYTOGENS: TWO GENERATIONS OF BIOREGULATORS
Khavinson's research produced two distinct categories of bioregulator compounds.
The first generation are Cytomaxes, also called cytomedins. These are crude peptide fractions extracted from specific animal organs, primarily bovine. Thymalin comes from bovine thymus. Epithalamin comes from bovine pineal gland. Cortexin comes from bovine brain cortex. Cytomaxes contain complex mixtures of peptide sequences extracted from the target organ tissue. They are not purified to a single defined compound. Their biological activity reflects the combined effect of multiple peptide sequences, which creates both clinical complexity and analytical difficulty. Because they are not defined by a single amino acid sequence, they are considerably harder to verify with standard analytical methods.
The second generation are Cytogens, the fully synthetic compounds. Once Khavinson's research had identified the specific short peptide sequences responsible for the biological activity within the crude Cytomax extracts, his team synthesized those sequences as standalone compounds. Epitalon (Ala-Glu-Asp-Gly, four amino acids) is the synthetic version of the active peptide sequence identified in Epithalamin. Vilon (Lys-Glu, two amino acids) is the synthetic dipeptide derived from thymic fractions. Thymogen (Glu-Trp, two amino acids) is another synthetic thymic derivative.
Cytogens offer the analytical advantages of pure single-compound synthesis. They can be characterized by mass spectrometry, tested for purity by HPLC, and verified by third-party independent laboratories in a way that complex tissue extracts cannot. For researchers who prioritize documented quality and analytical traceability, Cytogens are considerably more tractable than Cytomaxes. For a discussion of what COA tests actually mean in practice, see our COA guide.
THE COMPLETE KHAVINSON COMPOUND CATALOG
What follows is the full catalog of compounds produced through Khavinson's research program, organized by the target tissue each one was developed for. Where a synthetic Cytogen sequence exists, it is listed alongside its parent Cytomax. Cytogens are the sourcing priority from a quality verification standpoint because they have defined amino acid sequences that can be confirmed by mass spectrometry on a third-party COA. The Cytomax tissue extracts are significantly harder to verify analytically.
PINEAL GLAND
Epithalamin is the original Cytomax, a complex peptide extract from bovine pineal gland and the compound used in the foundational human longevity studies. The 266-patient mortality cohort data, showing up to 4.1-fold reduction in mortality when combined with Thymalin and administered annually, used Epithalamin.
Epitalon, also written Epitalon (Epithalon), is the Cytogen synthetic tetrapeptide with the sequence Ala-Glu-Asp-Gly (AEDG). It is the most internationally recognized Khavinson compound and the most researched single-sequence bioregulator in the Western market. The 2003 telomerase activation study, the 2025 independent Western replications confirming telomere extension, and a 2025 comprehensive review in International Journal of Molecular Sciences all focus on Epitalon specifically. It is scheduled for its first formal FDA PCAC review on July 24, 2026, under the insomnia indication. It is the clearest starting point for any researcher approaching this compound class for the first time.
Pinealon is the Cytogen tripeptide with the sequence Glu-Asp-Arg (EDP). Where Epitalon targets telomerase activity and melatonin restoration, Pinealon is directed at neuroprotective mechanisms through pineal-brain signaling. Research documents protection against oxidative stress in neurons, restoration of circadian rhythm regulation, and potential applications in neurodegenerative disease models. Being a defined three-amino-acid sequence, Pinealon is analytically tractable for third-party verification.
THYMUS AND IMMUNE SYSTEM
Thymalin is the Cytomax extract from bovine thymus gland. It is the immune system pillar of the Khavinson catalog. The thymus undergoes significant involution with age, driving the immune decline that makes older adults more vulnerable to infection, cancer, and autoimmune dysregulation. Phase 3 clinical trials in Russia documented a 2 to 2.4-fold reduction in acute respiratory infections in elderly subjects. Its combination with Epithalamin in the mortality cohort produced the most striking outcomes in the entire literature.
Vilon is the Cytogen dipeptide with the sequence Lys-Glu, derived from the thymic fraction. At two amino acids, it is one of the smallest biologically active peptides ever characterized. Animal longevity studies documented extended maximum lifespan when Vilon was administered throughout the animals' lives. Its analytical traceability as a defined dipeptide makes it the preferred sourcing target over the complex Thymalin extract for researchers who require COA documentation.
Thymogen is the Cytogen dipeptide with the sequence Glu-Trp, another synthetic derivative of thymic fractions. Its research profile centers on immune activation and T-cell modulation. It represents a distinct synthetic branch of thymic bioregulator research from Vilon and offers an alternative defined-sequence option for thymic immune support research.
Vladonix is the Cytogen targeting thymic and immune progenitor cells, with applications related to immune system restoration and bone marrow-thymic axis function. Less researched than Thymalin or Vilon but part of the systematic immune system coverage in Khavinson's catalog.
BRAIN AND CENTRAL NERVOUS SYSTEM
Cortexin is the Cytomax derived from bovine brain cortex, developed for neuroprotective and cognitive applications. Among all the Khavinson Cytomaxes, Cortexin has the most developed clinical evidence base for neurological applications. Russian clinical practice data documents normalization of cortical neuron function, reduction in vascular dementia progression, and improved outcomes in stroke rehabilitation. Its complex tissue extract nature makes third-party verification more challenging than for single-sequence Cytogens.
Pinealon appears here as well for its neuroprotective applications, distinct from its pineal-focused classification above.
Vesugen is the Cytogen tripeptide with the sequence Lys-Glu-Asp, targeting brain vascular tissue. Its research applications focus on cerebrovascular function, age-related changes in brain blood supply, and vascular contributions to cognitive decline. Vesugen represents the intersection of cardiovascular bioregulation and brain health in Khavinson's systemic approach.
CARDIOVASCULAR SYSTEM
Cardiogen is the Cytogen tetrapeptide with the sequence Ala-Glu-Asp-Arg, targeting heart muscle tissue. Research applications include cardioprotection, myocardial repair, and heart failure models. It represents Khavinson's systematic approach to cardiac aging biology and is among the more clinically relevant Cytogens for the cardiovascular longevity research space.
Cortagen is the Cytogen with the sequence Ala-Glu-Asp-Gly targeting cardiac and cortical applications. The listed research text specifies noting that this sequence is identical to Epitalon's AEDG sequence, which reflects the complexity of the Khavinson catalog where some compound designations refer to application context rather than unique sequences.
Vesugen, described above under CNS, also carries primary cardiovascular classification for its vascular tissue targeting.
LIVER
Svetinorm is the Cytogen tripeptide with the sequence Gly-His-Lys, targeting liver tissue. Liver function declines measurably with age, affecting detoxification capacity, protein synthesis, lipid metabolism, and glucose regulation. Svetinorm's research addresses hepatic gene expression restoration consistent with the broader bioregulator framework. Gly-His-Lys is also known as GHK and shares a sequence with the copper-binding peptide GHK-Cu, which has its own separate and extensive wound healing and anti-aging research literature (see our GHK-Cu stacking guide).
KIDNEYS
Renisamin is the Cytomax extract from kidney tissue, targeting renal function. Age-related kidney function decline is one of the most consistent and clinically significant features of aging biology. Renisamin represents Khavinson's systematic effort to address renal aging through tissue-specific bioregulator peptides, though it has a substantially thinner research profile than the pineal and thymic compounds.
RETINA AND EYES
Retinalamin is the Cytomax extract from retinal tissue, one of the more clinically developed visual system applications in the Khavinson catalog. Age-related retinal degeneration is a major driver of blindness and vision loss in older populations. Russian clinical applications include retinitis pigmentosa, diabetic retinopathy, and age-related macular changes. The 2025 Italian-Russian collaboration published in Stem Cell Reviews and Reports documented Epitalon's effects in retinal pigment epithelial cells under diabetic conditions, suggesting cross-compound retinal biology between the pineal and retinal branches of the catalog.
Visoluten is the Cytogen derivative developed for retinal applications, providing the defined-sequence analytical advantage over the complex Retinalamin extract for researchers requiring COA verification.
PROSTATE
Prostamax is the Cytomax extract from prostate tissue. Prostate function declines with age in ways that affect a significant proportion of older men. Prostamax research follows the standard Khavinson framework of tissue-specific gene expression restoration applied to prostatic tissue.
Libidon is the Cytogen tetrapeptide with the sequence Lys-Glu-Asp-Pro, the synthetic defined-sequence alternative for prostate-targeted bioregulator research.
FEMALE REPRODUCTIVE SYSTEM
Zhenoluten is the Cytogen targeting ovarian tissue, developed for female reproductive system applications including age-related ovarian function decline. It represents Khavinson's systematic coverage of the endocrine system, extending the bioregulator framework to female-specific tissue aging.
MALE REPRODUCTIVE SYSTEM
Testoluten is the Cytogen targeting testicular tissue, addressing age-related testicular function and male endocrine decline. Its research follows the same tissue-specific framework applied across the catalog.
JOINTS AND CONNECTIVE TISSUE
Sigumir is the Cytogen tetrapeptide with the sequence Ala-Glu-Asp-Pro, targeting cartilage and joint tissue. Age-related cartilage degradation is one of the most widespread sources of functional decline in older adults. Sigumir's research addresses chondrocyte gene expression and cartilage matrix maintenance through the bioregulator mechanism.
LUNGS AND RESPIRATORY SYSTEM
Chonluten is the Cytogen tripeptide with the sequence Gly-Glu-Pro, covering both lung tissue and connective tissue applications. Pulmonary aging affects gas exchange efficiency, respiratory muscle function, and airway resilience. Chonluten represents bioregulator research extended into the respiratory system.
Taxorest is the Cytogen specifically targeting lung tissue with a distinct research profile from Chonluten, addressing age-related pulmonary function decline through tissue-specific bioregulation.
THYROID
Thyreogen is the Cytogen dipeptide with the sequence Glu-Asp, targeting thyroid tissue. Thyroid function declines with age in ways that affect metabolism, body temperature regulation, cardiovascular function, and cognitive performance. Thyreogen is among the shortest and simplest Cytogens in the catalog, demonstrating that meaningful biological specificity is achievable at the two-amino-acid level.
ADRENAL GLANDS
Glandokort is the Cytogen targeting adrenal cortex tissue. Age-related changes in adrenal cortex function affect cortisol regulation, DHEA production, and stress response capacity. Glandokort represents the systematic extension of the Khavinson framework to adrenal biology.
PARATHYROID AND BONE
Bonothyrk is the Cytogen tripeptide with the sequence Glu-Asp-Arg, targeting parathyroid and bone tissue. Parathyroid hormone regulation of calcium metabolism is central to bone density maintenance. Age-related parathyroid dysfunction contributes to osteoporosis. Bonothyrk addresses this intersection of endocrine and skeletal aging.
SKELETAL MUSCLE
Gotratix is the Cytogen tripeptide with the sequence Lys-Glu-Asp, targeting skeletal muscle tissue. Age-related muscle loss, called sarcopenia, is one of the most functionally significant features of aging and is strongly associated with mortality, frailty, and loss of independence. Gotratix represents the muscle tissue application of the bioregulator framework, though its research base is thinner than the pineal and thymic compounds.
BLOOD AND BONE MARROW
Myelopid is the Cytomax derived from bone marrow, targeting hematopoietic and immune progenitor cell populations. Bone marrow function declines with age, affecting immune cell production, red blood cell generation, and the stem cell pool that supports tissue regeneration across the body.
Vladonix, listed above under the immune system, also covers this bone marrow-immune progenitor axis.
STOMACH AND GASTROINTESTINAL TRACT
Stamakort is the Cytogen tripeptide with the sequence Gly-Glu-Pro, targeting gastric mucosa tissue. Age-related changes in gastric function affect acid production, intrinsic factor secretion (critical for B12 absorption), and mucosal integrity. Stamakort represents the systematic extension of the bioregulator framework to digestive system aging.
PANCREAS
Suprefort is the Cytogen targeting pancreatic tissue, with metabolic applications related to insulin production, glucagon regulation, and pancreatic enzyme function. Age-related pancreatic decline contributes to metabolic dysregulation and type 2 diabetes risk. Suprefort occupies an interesting intersection between the longevity biology focus of most bioregulator research and the metabolic medicine applications that have driven mainstream peptide interest through GLP-1 receptor agonists.
THE KEY COMPOUNDS IN DEPTH: WHAT THE RESEARCH ACTUALLY SHOWS
With the full catalog established, the four compounds with the strongest research footprints and the most accessible third-party testing documentation in the current market deserve closer examination.
Epitalon
The telomere research is the headline story for Epitalon and deserves precise treatment because it is both genuinely significant and frequently overstated in community discussions. Khavinson's original 2003 study reported that Epitalon activates telomerase in cultured human somatic cells. Fibroblast cultures treated with Epitalon completed 44 passages versus 34 in controls. In 2025, two independent Western laboratory replications confirmed telomerase activation. Al-Dulaimi et al. (2025, PMID 40908429) showed Epitalon increases telomere length in human cell lines through both telomerase upregulation and alternative lengthening of telomeres pathways. That independent replication is significant. It means the flagship mechanism is not solely a product of Khavinson's own laboratory.
The mortality data from the 266-patient cohort is the most striking human evidence in the catalog. Epithalamin produced a 1.6 to 1.8-fold reduction in mortality over six years compared to controls. Combined with Thymalin, that reduction reached 2.5-fold. With annual combined administration, it reached 4.1-fold. Those are extraordinary effect sizes. The methodological honest caveat is that this was a non-blinded Russian clinical program, not a Western randomized placebo-controlled trial. Both things are true simultaneously: these are among the most developed human longevity data for any non-approved research compound, and they are not equivalent to Phase III RCT evidence.
A 2025 Italian-Russian collaboration published in Stem Cell Reviews and Reports extended Epitalon's mechanistic scope into diabetic retinopathy models, finding restoration of wound healing, reduction of reactive oxygen species, and inhibition of hyperglycemia-induced epithelial-mesenchymal transition in retinal cells. That is a meaningfully different application from longevity biology and demonstrates the breadth of the compound's potential research scope.
Thymalin
The immune system is the Thymalin story. Phase 3 clinical trials in Russia documented a 2 to 2.4-fold reduction in acute respiratory infections in elderly subjects. Its combination with Epithalamin in the mortality cohort produced the most striking outcomes in the entire literature and demonstrated that the pineal and thymic systems interact synergistically in ways that neither compound alone captures. For researchers approaching bioregulators for the first time, the Epitalon-Thymalin combination is the most evidence-supported starting point in the catalog.
Pinealon
Pinealon's research positions it as the neuroprotective branch of pineal gland biology, distinct from Epitalon's telomere and melatonin focus. Protection against oxidative stress in neurons, restoration of circadian rhythm regulation, and neurodegenerative disease model applications define its research profile. As a defined three-amino-acid Cytogen it offers full analytical traceability.
Cortexin
Among all Khavinson Cytomaxes, Cortexin has the most developed clinical evidence for neurological applications. Russian clinical data documents normalization of cortical neuron function, reduced vascular dementia progression, and improved stroke rehabilitation outcomes. Its complex tissue extract nature is the sourcing and verification challenge that distinguishes it from the more tractable Cytogen alternatives.
WHAT THE EVIDENCE GAP ACTUALLY MEANS
The honest assessment of Khavinson peptide evidence requires holding two things simultaneously without collapsing into either naive enthusiasm or reflexive skepticism.
The positive case is real. Four decades of research. 775 publications. Human cohort data showing mortality effects that would be considered extraordinary if they appeared in a Western randomized trial. Active replication of telomerase mechanisms by independent Western laboratories in 2025. A comprehensive review in a peer-reviewed open-access journal in 2025 synthesizing the evidence base. Carnyx Therapeutics, a US startup, publicly building a commercial program on the Khavinson research foundation. The FDA scheduling the first formal advisory committee review of Epitalon for July 2026. These are not the characteristics of fringe science.
The honest limitation is equally real. As of mid-2026, no Western-standard randomized placebo-controlled trial of any Khavinson bioregulator has been published. The strongest human evidence was conducted in a non-blinded Russian clinical program setting. The research base is substantially concentrated in Khavinson's own laboratory. Independent Western replication has been limited to in vitro telomere work, not clinical outcomes.
The gap between these two positions is not cause for dismissal. It is cause for exactly the kind of formal evaluation that the July 2026 PCAC proceeding represents. The scientific community has not proven that bioregulators do not work. It has proven that the evidence requires independent validation in controlled settings. Those are categorically different conclusions.
THE 2026 REGULATORY PICTURE
Epitalon was removed from FDA Category 2 status in April 2026, removing the prohibition on its compounding under the 503A framework. The PCAC review scheduled for July 24, 2026, evaluates Epitalon under the insomnia indication, reflecting the FDA's process of evaluating specific proposed uses rather than the full biological scope of the compound.
For the biological tissue extract Cytomaxes including Thymalin, Cortexin, and Epithalamin, the regulatory position is more complex. These complex tissue extracts do not meet standard 503A bulk drug substance criteria because they are not FDA-approved drug ingredients, do not have USP or NF monographs, and are not currently on the 503A bulk substances list. They exist in research-use channels outside the compounding pharmacy framework.
For the full regulatory context on how the 503A and 503B compounding frameworks apply to research peptides, see our 503A vs. 503B guide.
WHY THESE COMPOUNDS ARE GETTING SERIOUS ATTENTION NOW
Several forces converged simultaneously. The GLP-1 phenomenon demonstrated to a mainstream audience that peptides could produce biological effects of extraordinary magnitude in humans. The regulatory contraction around conventional research peptides in 2023 pushed the research community to look harder at compounds outside the enforcement crosshairs. Longevity biology moved from a niche academic interest to a mainstream cultural conversation. And Khavinson's death in January 2024 paradoxically accelerated Western interest by prompting retrospective surveys of his work that introduced the research to audiences who had not previously encountered it.
The bioregulator concept is also genuinely compelling on its scientific merits. If aging is fundamentally a problem of gene expression dysregulation rather than irreversible damage accumulation, then compounds that address gene expression directly represent a categorically different approach to longevity than antioxidants, caloric restriction mimetics, or senolytic drugs. Whether that hypothesis holds up to the Western clinical trial scrutiny it has not yet fully received is the central open question. But the hypothesis is serious, the mechanism is biologically plausible, and the human data points in a consistent and striking direction.
For vetted vendor information and current coupon codes for vendors carrying Khavinson-category research compounds with documented third-party testing, browse our vendor directory. For a plain-language refresher on terms like bioregulator, Cytomax, and Cytogen, see our peptide glossary.
For research and educational purposes only. Not medical advice. Research peptides are not FDA-approved for human use.