HEP-1 (Human Ezrin Peptide One)
Gepon, Hepon, ezrin peptide, HEP1, TEKKRRETVEREKE
HEP-1, marketed in Russia as gepon since 2001, is a synthetic 14-residue peptide whose sequence derives from a region of human ezrin. Its developers propose that it suppresses inflammatory cytokines while enhancing adaptive immunity, but no receptor has been molecularly identified and the human literature consists of small uncontrolled Russian reports plus a narrative review written by the peptide's own inventors.
Mechanism
HEP-1 is a synthetic 14-residue peptide, TEKKRRETVEREKE, whose sequence derives from a region of human ezrin, a cytoskeletal linker of the ERM (ezrin/radixin/moesin) family that tethers the plasma membrane to the actin cytoskeleton and participates in immune synapse formation and lymphocyte polarisation. The peptide is strikingly charged: it contains three lysines, three arginines and five glutamates, giving it a highly polar, alternating-charge character. Note that this makes it close to charge-neutral overall at physiological pH, not strongly cationic, a point sometimes misstated in secondary descriptions, including in an earlier version of this entry.
The proposed mechanism, advanced principally by Holms and Ataullakhanov, is that HEP-1 engages a putative cell-surface 'Hep receptor' (described as a structure mimicked by the ezrin region from which the peptide is drawn, and, on their account, also resembled by the C-terminus of HIV gp120) and thereby suppresses pro-inflammatory cytokine output while enhancing adaptive B- and T-cell responses to viral antigen. Downstream reports describe induction of interferon-alpha and modulation of mucosal cytokine profiles.
This needs to be read carefully. No receptor has been molecularly identified, cloned, structurally characterised, or validated by any group independent of the originators. There is no published binding affinity, no receptor knockout or knockdown experiment establishing necessity, and no independent replication of the signalling claims. The mechanism as stated is a hypothesis under advocacy by its proponents, not an established pathway, and it should not be presented to readers as settled pharmacology. A simultaneous claim of inflammatory cytokine suppression and adaptive immune enhancement is also biologically demanding (those are not usually co-directional effects) and would require strong evidence to accept, which has not been produced.
What the research shows
Gepon has been a registered medicine in Russia since 2001, and that regulatory status is frequently presented as though it constituted an evidence base. It does not. The published human literature is dominated by small, mostly uncontrolled Russian-language reports across a scattered set of indications: an assessment in 37 patients with chronic tonsillitis undergoing tonsillectomy, concluding that local application after surgery was justified (Starosvetskiĭ, 2005); a study of salivary immune and oxidative markers in 67 patients with exacerbated chronic apical periodontitis, in which gepon was administered only as one component of a multi-drug combination and so cannot be isolated as the active agent (Konoplya, 2017); and experimental antiviral work against herpes simplex virus types 1 and 2 showing up to 100-fold viral titre reduction with preventive administration (Barinskiĭ, 2003, which is laboratory and animal work rather than clinical).
The principal English-language synthesis is a 2021 narrative review in the International Journal of Molecular Sciences by Holms and Ataullakhanov, the peptide's developers. It describes uncontrolled series in HIV-associated opportunistic infection (candidiasis, herpes recurrence), gastrointestinal conditions, and use as an inhaled spray in mild-to-moderate COVID-19. The authors themselves characterise the results as preliminary and explicitly call for large-scale randomised placebo-controlled clinical studies. That is a fair self-assessment and should be taken at face value. A review written by a compound's inventors is a legitimate source for describing what they claim, but it is not independent evidence, and readers should weight it accordingly.
The registry position is stark. One phase 1 study of HEP-1 in COVID-19 is registered (NCT04627233, 20 participants, sponsored by Shahid Beheshti University of Medical Sciences in Iran, not by a Russian institution, contrary to what is sometimes assumed), with status listed as unknown and no results posted. Beyond that, there are no registered trials. No randomised, double-blind, placebo-controlled trial of HEP-1 for any indication appears in the indexed international literature, and there is no independent replication of any efficacy claim outside Russia. A quarter-century of registration in one jurisdiction has produced no evidence package that would be recognised by the FDA, EMA or MHRA.
Evidence assessment
Limited evidence
Human data exist and the compound has been registered in Russia since 2001, but the published record consists of small uncontrolled Russian-language series (including one in which gepon was given only as part of a multi-drug combination) plus a narrative review authored by the compound's own developers; no randomised double-blind placebo-controlled trial is indexed internationally, and the only registered trial (a 20-participant phase 1) has posted no results and its status is listed as unknown.
Tiers are applied consistently across the library and re-checked when new trials read out. Read the grading method.
Key studies
Ezrin Peptide Therapy from HIV to COVID: Inhibition of Inflammation and Amplification of Adaptive Anti-Viral Immunity Limited evidence
Describes uncontrolled reports in HIV-associated opportunistic infection, gastrointestinal disease and inhaled-spray use in mild-to-moderate COVID-19; the authors characterise the results as preliminary and explicitly call for large-scale randomised placebo-controlled clinical studies.
Administration of the immunomodulator gepon after tonsillectomy Limited evidence
Concluded that local application of gepon after bilateral tonsillectomy is justified and could be recommended for clinical practice, based on immunological assessment in the early postoperative period.
The antiviral activity of peptide immunomodulator 'Gepon' in experimental infections caused by herpes simplex viruses types 1 and 2 Preclinical only
Reported non-toxic antiviral activity without direct virucidal action; preventive administration achieved maximal viral titre reduction of about 100-fold, exceeding the effect of post-infection administration.
Local immune and oxidative status in exacerbated chronic apical periodontitis Limited evidence
Reported disturbed cytokine balance, complement activation and increased lipid oxidation, with the best restoration of these surrogate markers achieved by combining gepon or an enzyme preparation with two further adjunctive agents.
The Clinical Trial of Application of Ezrin Peptide (HEP-1) for Treatment of Coronavirus Disease (COVID-19) Infection Limited evidence
No results have been posted; the registry status is listed as unknown.
Safety
There is no adequate safety database for HEP-1. Russian marketing materials and the developers' review describe it as well tolerated across topical, oral, inhaled and injected routes, and the 2003 herpes simplex work described it as non-toxic in the laboratory, but none of the underlying human reports involve systematic adverse event ascertainment, defined follow-up periods, or independent monitoring. In this setting, 'no adverse effects reported' means adverse effects were not systematically sought, which is a different claim entirely.
Specific gaps worth naming: no controlled study has examined use in autoimmune disease, in transplant recipients, in pregnancy, or alongside immunosuppressive or immune-checkpoint therapy, the situations in which an agent claiming to modulate both cytokine output and adaptive immunity would matter most. There are no long-term data of any kind. And because the proposed mechanism includes suppression of pro-inflammatory cytokine output, the theoretical risk of blunted responses to infection has not been evaluated. Material sold outside Russia has no verified identity, purity, sterility or endotoxin testing, and for an injected product those are the failure modes that cause real-world harm irrespective of the molecule's intrinsic properties.
Regulatory status
| Jurisdiction | Status |
|---|---|
| United Kingdom | No MHRA marketing authorisation. Not a licensed medicine in the UK. |
| United States | Not approved by the FDA and never submitted for approval. One phase 1 trial is registered (NCT04627233, n=20, COVID-19, sponsored by Shahid Beheshti University of Medical Sciences) with status listed as unknown and no results posted. Sold internationally under 'research use only' labelling, which permits distribution of an unapproved compound rather than indicating any regulatory assessment. |
| WADA (sport) | Not named on the WADA Prohibited List. Athletes should note section S0 (unapproved substances), which prohibits pharmacological substances not addressed elsewhere and not currently approved by any governmental regulatory health authority for human therapeutic use; HEP-1's Russian registration complicates rather than settles that analysis, and a formal ruling should be sought. |
Questions
They are the same compound. HEP-1 (Human Ezrin Peptide One) is a synthetic 14-amino-acid peptide, TEKKRRETVEREKE, derived from a region of human ezrin. It has been registered for human use in Russia under the name gepon since 2001. BioRx uses the research designation HEP-1 rather than the Russian product name.
No. There is no randomised, double-blind, placebo-controlled trial of HEP-1 for any indication in the indexed international literature. The published human record consists of small uncontrolled Russian-language series (one of which gave gepon only as part of a multi-drug combination) and a 2021 narrative review written by the peptide's own developers, who themselves describe the results as preliminary and call for large randomised trials. The single registered trial, a 20-participant phase 1 in COVID-19, has posted no results and its status is listed as unknown.
Its developers propose that it binds a cell-surface 'Hep receptor' mimicking a structure in human ezrin, suppressing inflammatory cytokine output while enhancing B- and T-cell responses to viruses. It is important to be clear that no such receptor has been molecularly identified, cloned, or confirmed by any independent group, and no binding data have been published. This is a proposed mechanism, not a demonstrated one.
No. Registration in Russia reflects that country's regulatory pathway, not an evidence standard equivalent to FDA, EMA or MHRA approval. A quarter-century of registration has not produced a single randomised controlled trial in the international literature or any independent replication outside Russia. Regulatory status in one jurisdiction and clinical evidence are different things, and conflating them is a common error in peptide marketing.