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A specimen of the Immune drawer Drawer F · Immune

Thymogen

Research Only

A synthetic dipeptide (glutamyl-tryptophan) developed in Russia as a defined successor to thymalin. Approved in Russia for immunomodulation with extensive Russian clinical literature. Represents an attempt to create a standardized, synthetic thymic peptide. Not approved by Western regulatory agencies.

Glu-Trp · EW dipeptide · Timogen · Glutamyl-Tryptophan · L-Glu-L-Trp

Research evidence
Moderate

6 human studies

Preclinical
76%
Clinical
24%

Based on 25 cited sources

Evidence Score48/100
Early / limited
Research Depth40/100
Mechanism40/100
Plausibility67/100
Global Coverage55/100
Community Experience45/100
Effectiveness35/100

clinically demonstrated · very-low confidence

Demonstrated effect magnitude — not a recommendation or safety claim.

Research Depth 40: best human evidence is uncontrolled open-label Russian clinical-observation (Zhuk & Galenok 1996, PMID 9026934, clinical effect in 94.4% of T1D secondary-immunodeficiency patients) plus Morozov & Khavinson 1997 (9637345) clinical-use reports — 1A single uncontrolled open-label human tier (15), 1B high RoB (5, no blinding/control), 1C small total N 50-300 (5), 1D direct population+outcome match to the Russian-approved immunodeficiency indication (9), 1E substantial multi-model preclinical program incl. Anisimov 2000 rat aging/carcinogenesis (11707921) and the Kursk hepatoprotection series (6). Mechanism 40: 2A target only inferred — no named receptor with binding affinity (10); 2B proximal MAPK->TNF/IL-6 and IL-2/IFN-gamma signaling partially characterized in vitro (Avolio 2022, 35408963) (13); 2C dose comparisons in hepatoprotection models (9); 2D confirmed in in-vivo mammalian (rat) models (8). Plausibility 67: 3A mechanism->surrogate (T-cell/cytokine markers) established, surrogate-> clinical benefit inferred (22); 3B coherent with thymic-peptide biology (20); 3C same-class analogues (thymosin alpha-1, thymalin, thymulin) show analogous immunomodulation (15); 3D moderately broad (immune + aging/anti- tumor) (10). Global Coverage 55: 4A independent replication by an Italian group (Avolio 2022) and an independent Russian group (Kursk, 37861903 / 40442470) lifts above single-lab (18); 4B Russia + Italy, 2-3 countries (12); 4C ~20-100 directly-relevant studies, broad Glu-Trp PubMed count inflated by unrelated whey-tripeptide/metabolite hits (15); 4D registered in Russia as an immunomodulator, one national regulator (10). Community Experience 45: 5A niche but persistent enthusiast discussion (10); 5B >3-year sustained track record, Russian approval since the 1990s (16); 5C sparse but broadly consistent reports (8); 5D no recurring serious adverse signal over substantial Russian clinical exposure (11) — usage signal only, not a safety claim. Effectiveness basis clinical (35, very-low confidence): a quantified human efficacy estimate exists (Zhuk & Galenok 94.4% clinical response) but it is uncontrolled, open-label, single-group Russian data with no placebo, so magnitude (E1 12), MCID (E2 9), intermediate/functional outcome relevance (E3 8) and superiority-vs-placebo-on-surrogate-only (E4 6) are all scored conservatively with a Very Low confidence flag.

Scored June 2026 How we rate →
~
Evidence Level
moderate
Not approved for human use by any regulatory agency
Limited human clinical trial data
Consult a healthcare provider before use
Not FDA Approved WADA Prohibited
Identity
SCALE · 1:1 N-TERMINUS C-TERMINUS 2 AA · 333.34 Da
Also Known As
Glu-Trp • EW dipeptide • Timogen • Glutamyl-Tryptophan • L-Glu-L-Trp
Class
Dipeptide
Length
2 amino acids
Mol. weight
333.34 Da
Sequence
EW
Molecular Structure
E
W
Hydrophobic
Polar
Positive
Negative

The proposed mechanisms of Thymogen are based on Russian clinical studies, animal research, and in vitro experiments. Western-standard mechanistic validation is lacking.

How It Works (Simplified)

Thymogen appears to act as an immunomodulatory signal through several pathways:

T-Cell Modulation

Activates T-cell differentiation and enhances T-cell recognition of peptide-MHC complexes, supporting adaptive immune function.

Cytokine Regulation

Modulates IL-2, IFN-gamma, TNF, and IL-6 production, potentially balancing pro- and anti-inflammatory responses.

Innate Immunity

Activates neutrophil chemotaxis and phagocytosis, enhancing the first-line immune defense against pathogens.

Epigenetic Effects

May interact with DNA promoter regions in lymphocytes, transforming heterochromatin to euchromatin and activating gene transcription.

Key Research: Morozov VG & Khavinson VK (Russia, 1997) demonstrated T-cell differentiation and cytokine modulation in clinical settings. PMID:9637345

Important Limitations

  • Most clinical studies conducted in Russia with variable methodology
  • Specific receptor for Thymogen not definitively identified
  • Mechanism by which a rapidly-degraded dipeptide exerts lasting effects remains unclear
  • Translation to Western clinical standards is unconfirmed
  • Bioavailability and pharmacokinetics not fully characterized
i. T-Cell Differentiation Pathway · Adaptive Immunity
ThymogenT-cell receptor signalingMHC complex recognition enhancementT-lymphocyte differentiation & activation
ii. Cytokine Modulation Pathway · Inflammation Control
ThymogenMAPK pathway modulationReduced TNF/IL-6Anti-inflammatory effectIL-2/IFN-gamma regulationBalanced immune response
Mechanism T-cell differentiation and MHC complex recognition enhancement
Supported 5 direct studies
Benefit may restore immune function in immunodeficient states
Evidence Level
Low
3 Human
4 Animal
2 In Vitro
Mechanism Cytokine modulation including IL-2 and IFN-gamma regulation
Supported 4 direct studies
Benefit appears to modulate inflammatory and immune responses
Evidence Level
Low
2 Human
3 Animal
3 In Vitro
Mechanism DNA-peptide interaction and epigenetic gene regulation
Emerging 3 direct studies
Benefit suggested to slow aging processes and reduce tumor incidence
Evidence Level
Very Low
2 Animal
2 In Vitro
Mechanism Confidence
Established
Supported
Emerging
Evidence Level
High
Moderate
Low
Very Low
Phase 01 1
Week 1-2

Based on Russian clinical reports: Initial immunomodulatory effects may begin. T-cell differentiation markers may start to normalize. Cytokine profile changes observed in some studies. No Western-standard pharmacokinetic data available.

PMID:9637345
Phase 02 2
Week 2-4

Russian clinical protocols typically show continued immune parameter improvements. IL-2 and IFN-gamma modulation reported. Neutrophil function enhancement observed in some studies.

PMID:9026934
Phase 03 3
Week 4-8

Extended treatment courses in Russian protocols suggest sustained immunomodulatory effects. Secondary immunodeficiency markers reportedly normalize in majority of patients in Russian studies.

PMID:9637345
Phase 04 4
Week 8+

Long-term data comes primarily from Russian observational studies. Duration of effect after discontinuation not well characterized. Optimal treatment length remains undefined by Western standards.

Research-based observations

This timeline reflects observations from published clinical and preclinical studies. Individual responses may vary significantly. This is not a guarantee of effects or a dosing schedule. Consult qualified healthcare providers for personalized guidance.

Good Signs (6 indicators)
White to off-white lyophilized powder
Dissolves quickly and completely in bacteriostatic water
Clear, colorless solution after reconstitution
Certificate of analysis (COA) showing >95% purity
Third-party HPLC verification available
Proper vacuum seal on vial before reconstitution
Warning Signs (5 indicators)
Slightly off-white powder (may still be acceptable for dipeptides)
Takes longer than expected to dissolve
Powder appears collapsed or clumped (possible moisture exposure)
COA from manufacturer only without third-party verification
Purity listed below 95% but above 90%
Bad Signs (6 indicators)
Yellow, brown, or otherwise discolored powder
Visible particles or cloudiness after reconstitution
Gel-like consistency that won't dissolve
No COA provided or COA appears fraudulent
Strong unusual odor
Vial seal appears compromised or previously opened
Positive quality indicator
Requires evaluation
Potential quality issue

For Research Evaluation Only

These quality indicators are general guidelines based on typical peptide characteristics. Professional laboratory testing (HPLC, mass spectrometry) provides definitive quality verification. This checklist is for initial visual evaluation only.

Synergistic
Compatible
Caution
Avoid

Thymogen is derived from thymalin research. Both modulate thymic immune pathways. Concurrent use may have overlapping effects on T-cell differentiation. No direct studies on combination.

Both are thymic-derived immunomodulators with complementary mechanisms. Thymosin Alpha-1 has broader regulatory approval and more Western clinical data. No known contraindications to combination.

Different thymic peptides with overlapping immunomodulatory goals. Thymulin requires zinc as cofactor while Thymogen does not. Theoretical complementary effects on T-cell function.

Non-overlapping mechanisms. Thymogen modulates immune function while BPC-157 promotes tissue repair. May provide complementary benefits in recovery contexts.

LL-37

Compatible
Compatible

LL-37's antimicrobial and immunomodulatory properties may complement Thymogen's T-cell modulation. Both affect immune function through different pathways.

Both are Russian-developed peptides from Khavinson research. Epithalon targets telomerase while Thymogen targets immune function. Theoretical synergy in anti-aging protocols.

Research Note: Interaction data is based on published literature, mechanistic understanding, and theoretical considerations. Most peptide combinations lack direct clinical study. This information is for educational purposes only and does not constitute medical advice. Always consult qualified healthcare providers.

25 Sources 6 Human 19 Preclinical

Full reference list available on request. All citations link to PubMed for verification.

This dossier synthesizes available evidence from peer-reviewed literature, regulatory documents, and clinical trial registries. Evidence strength ratings follow a modified GRADE approach.

For complete methodology details, see our Methodology page.

Important Disclaimer

This dossier is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before making health decisions.

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