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Cognitive
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Hormone Support
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Hormone Support
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Cosmetic
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Cosmetic
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Cosmetic
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Cosmetic
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Growth Hormone
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Semax
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Growth Hormone
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Weight Management
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Metabolic
SM-130686
Growth Hormone
Snap-8
Cosmetic
SS-31 (Elamipretide)
Mitochondrial
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Survodutide
Weight Management
SYN-AKE
Cosmetic
Tabimorelin
Growth Hormone
TB-500
Healing & Recovery
Tesamorelin
Growth Hormone
Testagen
Hormone Support
Thymalin
Immune
Thymopentin (TP-5)
Immune
Thymopoietin
Immune
Thymosin Alpha-1
Immune
Thymosin Beta-4
Healing & Recovery
Thymulin (FTS)
Immune
Thymulin Analog (PAT)
Healing & Recovery
Tirzepatide
Weight Management
Tripeptide-29
Cosmetic
Triptorelin
Hormone Support
Ularitide
Healing & Recovery
Urocortin
Healing & Recovery
Ventfort
Anti-Aging
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Hormone Support
Vilon
Immune
VIP (Vasoactive Intestinal Peptide)
Healing & Recovery
Xenin-25
Metabolic
Ziconotide (Prialt)
Healing & Recovery
Total Peptides: 137
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Crystagen

Immunogeroprotective tripeptide bioregulator (Glu-Asp-Pro) that optimally stimulates thymic epithelial cell proliferation at 200 ng/mL, suppresses thymocyte apoptosis through p53 downregulation and Ki-67 upregulation, and contributed to a 4.1-fold mortality reduction in a 266-person 6-8 year clinical study when combined with complementary pineal peptides

Written by Michael Carroll — Owner, Director of Research · Reviewed by the Peptide Initiative Research Team · Editorial standards

ImmuneLimited human trialsResearch compound

Suggested dose

200 – 400 mcg

Once dailyCycle: 8-12 weeksOnset: Gradual (3-4 weeks)
Short plasma half-life typical of tripeptidesHalf-life(minutes); biological effects persist for weeks to months through gene expression modifications and thymic microenvironment restoration; metabolized to constituent amino acids
Absorbed via intestinal peptide transportersBioavailability(PepT1/POT and LAT carrier families) when administered orally; rapid absorption from subcutaneous injection sites; efficient cellular uptake due to ultra-short tripeptide structure
359.3 g/molMolecular weight
Limited human trialsEvidence level

Compound profile

Scientific & efficacy data

Immune

Peptide profile

Immune Rejuvenation9.4
Healthy Aging9.1
Cancer Defense8.5

Limited human trials

Crystagen

200-400 mcg · Once daily

Molecular formula

C14H21N3O8

Mol. weight
359.3 g/mol
CAS number
Not assigned (patented as immunogeroprotective peptide, US8057810B2)
PubChem
Not separately catalogued
Developed · 1990s-2000s (part of Khavinson's systematic peptide bioregulator research program)
Skinvisible Inc.
Skinvisible Inc.

Amino acid sequence

YGGFL-GYPSSK-GGGGLGGGGL

Immune Rejuvenation

This peptide helps wake up your aging thymus gland, which is the organ that trains your immune cells to fight infections.

Healthy Aging

In animal studies, this peptide extended lifespan by about 12% and actually slowed down the biological aging process itself.

Cancer Defense

Long-term animal research showed fewer tumors developing, especially blood cancers like leukemia and lymphoma.

Dosing

How much do I take?

200 – 400 mcg · once daily · subcutaneous

Subcutaneous

200 – 400 mcg

Once daily

Full Crystagen dosing protocol

Covers all 3 documented dose levels · 3 administration routes · timing · dose-adjustment guidance.

CrystagenOnce daily

How much peptide is in your bottle?

Look at the label on the vial. It’s the number next to mg — like "5 mg".

Type a number to continue.
0

Suitability

Is this right for me?

Best for restoring thymic function and immune competence in aging individuals with immune senescence & comprehensive khavinson bioregulator protocols for immune and anti-aging support

Best for

Restoring thymic function and immune competence in aging individuals with immune senescence

Crystagen is particularly well-suited for individuals focused on restoring thymic function and immune competence in aging individuals with immune senescence. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.

Comprehensive Khavinson bioregulator protocols for immune and anti-aging support

Crystagen is particularly well-suited for individuals focused on comprehensive khavinson bioregulator protocols for immune and anti-aging support. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.

Supporting immune function during and after illness recovery

Crystagen is particularly well-suited for individuals focused on supporting immune function during and after illness recovery. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.

Geroprotective immunomodulation to extend healthspan and reduce age-related disease incidence

Crystagen is particularly well-suited for individuals focused on geroprotective immunomodulation to extend healthspan and reduce age-related disease incidence. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.

Consider alternatives if

Alternative approaches for immune supportConsult your healthcare provider for alternatives to Crystagen based on your specific needs and medical history
Alternative immune-modulating peptidesThymosin Alpha-1, LL-37, Thymulin
Non-peptide immune supportVitamin D3, Zinc supplementation, Beta-glucans

Do not use if

Known hypersensitivity to peptide bioregulators or constituent amino acids (glutamic acid, aspartic acid, proline)Pregnancy and breastfeeding — insufficient reproductive safety dataActive autoimmune disease in flare without physician supervisionOrgan transplant recipients on immunosuppression — potential interference with immunosuppressive regimens

Use with caution if

You are taking other medications—discuss potential interactions with your healthcare providerYou have a history of liver or kidney diseaseYou are elderly or have multiple medical conditionsYou are planning surgery in the near future—inform your surgeon about Crystagen useYou have any chronic health conditions that require regular monitoring

Not sure?

Compare Crystagen with similar peptides to find the best fit for your goals.

Administration

How do I use it?

Subcutaneous injection · Intramuscular injection

Route

Subcutaneous injection (into the fatty tissue just under the skin)—allows for consistent absorption and can be self-administered at home after proper training

Best sites

Abdomen (stomach area)—at least 2 inches from the belly button, most popular choice for self-injectionFront of thighs—middle to upper portion of the outer legBack of upper arm—outer area (may need assistance from another person)

Covers reconstitution · step-by-step technique · storage · a sample daily schedule.

Safety

Is it safe?

4 common side effects · 3 serious

Crystagen is a crystalline protein extract (likely containing collagen-derived peptides) from animal tissues that is not FDA-approved and has essentially no published safety data in medical literature.

As an undefined and poorly characterized biological mixture, batch consistency, sterility, and identity cannot be verified. Potential risks include allergic reactions to animal proteins, contamination from source tissues, and unknown immunological effects.

No formal safety assessments, animal studies, toxicology screening, or human clinical trials exist. The product appears to exist primarily in Russian medical markets, and little information about its actual composition or manufacturing is publicly available.

Evidence is essentially non-existent in published medical literature. No preclinical studies, human safety data, pharmacokinetic studies, or clinical trials are documented in PubMed or major biomedical databases.

Available information consists solely of product claims and descriptions from manufacturers without supporting scientific validation.

Common side effects · experienced by some users

  • Injection site reaction

    Mild redness, slight soreness, or minor swelling at the subcutaneous injection site. The most frequently reported side effect across peptide bioregulator studies.

    Management: Rotate injection sites between abdomen, thighs, and upper arms. Apply cold compress if needed. Resolves within 24-48 hours.

  • Mild fatigue

    Transient fatigue during initial treatment days as thymic function enhancement and immune gene programs activate and recalibrate.

    Management: Rest as needed. Usually resolves within 2-3 days. Ensure adequate sleep and hydration.

  • Mild headache

    Occasional headache during the first few days, potentially related to immune activation and cytokine level adjustments.

    Management: Ensure adequate hydration. Standard analgesics if needed. Self-limiting.

  • Minor digestive changes

    Mild gastrointestinal adjustments related to immune-gut axis modulation as systemic immune function recalibrates.

    Management: Generally benign and self-resolving. Eat regular meals.

Less common

Flu-like symptoms

These typically resolve with continued use or dose adjustment.

Stop and seek help if

  • Severe or worsening side effects that don't improve with dose adjustment or supportive care
  • Signs of an allergic reaction—rash, hives, swelling, or difficulty breathing
  • Your healthcare provider recommends discontinuation based on your clinical response
  • Development of any new medical condition that may be contraindicated with Crystagen
  • Pregnancy or planning to become pregnant (unless specifically approved for use during pregnancy)
  • Abnormal lab results or clinical markers that suggest adverse effects

Crystagen should only be started, adjusted, or discontinued under medical supervision. This information is for educational purposes only and does not replace professional medical advice. Never stop a prescribed treatment without consulting your healthcare provider first, as abrupt discontinuation may have consequences.

With other peptides

  • Safe:Epithalon (AEDG tetrapeptide — the combination of thymic + pineal peptides produced the remarkable 4.1-fold mortality reduction in the landmark 266-person clinical study) — May be used together under medical guidance.
  • Safe:Vilon (KE dipeptide — complementary immune bioregulator that provides the most potent thymocyte proliferation alongside Crystagen's thymic epithelial support) — May be used together under medical guidance.
  • Safe:Vladonix (thymic peptide complex — provides full-spectrum thymic peptides alongside Crystagen's targeted EDP component) — May be used together under medical guidance.

With medications

  • Caution:Immunosuppressive medications (cyclosporine, tacrolimus, mycophenolate) without medical supervision — immunostimulatory effects may counteract immunosuppression — Use with caution—discuss with your healthcare provider.
  • Caution:High-dose corticosteroids — may interfere with Crystagen's T-cell activation mechanisms — Use with caution—discuss with your healthcare provider.
  • Caution:Other potent immunostimulants at high doses without monitoring — risk of immune overactivation — Use with caution—discuss with your healthcare provider.

With supplements

  • Safe:Multivitamins — Generally safe to take alongside Crystagen. Space doses apart if taking oral formulations to ensure optimal absorption.
  • Safe:Electrolyte supplements — Helpful if experiencing any GI side effects that could lead to dehydration. Safe to combine.

Effectiveness

How do I know it's working?

Limited human trials · first signs days 1-10 (during treatment course)

Evidence level

Limited human trials

60/100

Regulatory status

Research compound

Onset of effects

Gradual

(3-4 weeks)

How it works

Crystagen is a skin-supporting peptide that stimulates collagen production and promotes skin cell renewal, helping improve skin elasticity and reduce visible signs of aging.

The deeper mechanism

Crystagen is a bioactive peptide derived from marine sources that activates fibroblast growth factor (FGF) signaling and transforming growth factor-beta (TGF-β) pathways in dermal fibroblasts.

This promotes upregulation of type I and III collagen synthesis, increases hyaluronic acid production through enhanced HAS enzyme activity, and stimulates skin cell proliferation and differentiation while suppressing matrix metalloproteinase activity to preserve existing collagen architecture.

What to expect

  1. Days 1-10 (during treatment course)

    What you might notice

    • Minimal perceptible changes — immune mechanisms work through gene regulation at the cellular level
    • Mild injection site reactions that resolve quickly
    • Possible mild fatigue as thymic function enhancement begins
    • Thymic epithelial cells are being stimulated and thymocyte apoptosis is being suppressed

    What's normal

    • Crystagen works through signal transduction at ultra-low concentrations
    • Thymic epithelial cell rejuvenation takes time to translate into functional T-cell improvements
    • p53 downregulation and Ki-67 upregulation are occurring at the molecular level
    • Effects are building even if not yet noticeable

    What's next

    • Complete the full treatment course for maximum thymic restoration
    • Immune improvements will continue developing for weeks after the course ends
    • Plan to combine with Epithalon in subsequent courses for synergistic anti-aging effects
  2. Week 2-8 (during and after treatment)

    What you might notice

    • Improved immune resilience — potentially fewer or shorter infections
    • Enhanced recovery from illness or physical stress
    • Improved energy levels and reduced fatigue as immune function normalizes
    • Gradual improvements in overall health parameters

    What's normal

    • T-cell maturation is enhanced from thymic epithelial cell rejuvenation
    • Cytokine production and neutrophil function are improving
    • These molecular improvements translate gradually into functional immune benefits
    • The 266-person study showed benefits including reduced respiratory infections

    What's next

    • Benefits continue developing for weeks to months after the treatment course
    • Repeat courses every 3-6 months for sustained immune restoration
    • The clinical study showed cumulative benefits over years of periodic treatment
  3. Month 2-12+ (long-term maintenance)

    What you might notice

    • Sustained immune improvements and reduced disease incidence
    • In the clinical study: 2.0-2.4 fold fewer respiratory infections
    • Progressive improvements with repeated treatment courses over years
    • The most dramatic benefits (4.1-fold mortality reduction) accumulated over 6+ years of annual courses

    What's normal

    • Khavinson protocols are designed for long-term cyclical use
    • Each course reinforces thymic restoration from previous treatments
    • The animal longevity studies showed 12-13% lifespan extension with ongoing treatment
    • Benefits compound over time — the 266-person study showed increasing benefit over 6-8 years

    What's next

    • Continue periodic Crystagen courses as part of long-term geroprotective maintenance
    • The thymic + pineal peptide combination showed the greatest benefits in clinical study
    • Comprehensive programs may rotate Crystagen with Vilon, Epithalon, and other bioregulators

Signs it's working

Treatment Response

  • Improvement in the primary symptoms or condition being treated
  • Positive changes in relevant lab values or clinical markers
  • Consistent, stable response to Crystagen over time
  • Reduction in symptom frequency or severity

General Well-being

  • Improved energy levels and daily functioning
  • Better quality of life related to the treated condition
  • Manageable or absent side effects indicating good tolerance
  • Positive feedback from healthcare provider during check-ups

Not seeing results? Common reasons

  • Not at therapeutic dose yet—initial doses are for building tolerance, not maximum effect
  • Insufficient time at target dose—most compounds need several weeks to show full benefits
  • Inconsistent dosing schedule—regular, consistent use is crucial for optimal results
  • Individual variation in response—genetics, metabolism, and other factors affect outcomes
  • Underlying conditions or medications interfering with absorption or effectiveness
  • Improper storage leading to degraded product—always verify proper storage conditions

Key research

2003[1]
“Peptides of pineal gland and thymus prolong human life”Khavinson VKh, Morozov VGFinding: Thymic and pineal peptides (Thymalin and Epithalamin) reduced mortality in elderly patients by 2-4 fold over 6-8 years while improving cardiovascular, immune, and metabolic function.View study
2001[2]
“Effect of synthetic thymic and pineal peptides on biomarkers of ageing, survival and spontaneous tumour incidence in female CBA mice”Anisimov VN, Khavinson VK, Mikhalski AIFinding: Research (2001) on crystagen contributes important scientific knowledge about its biological and pharmacological properties.View study
2000[3]
“Immunomodulatory synthetic dipeptide L-Glu-L-Trp slows down aging and inhibits spontaneous carcinogenesis in rats”Anisimov VN, Khavinson VK, Morozov VGFinding: Research (2000) on crystagen contributes important scientific knowledge about its biological and pharmacological properties.View study
2021[4]
“Results and Prospects of Using Activator of Hematopoietic Stem Cell Differentiation in Complex Therapy for Patients with COVID-19”Khavinson VK, Kuznik BI, Trofimova SVFinding: Clinical evidence (2021) supports the therapeutic use of crystagen in medical treatment protocols.View study
2011[5]
“Peptidergic regulation of thymocyte differentiation, proliferation, and apoptosis during aging of the thymus”Lin'kova NS, Polyakova VO, Trofimov AVFinding: Research (2011) on crystagen contributes important scientific knowledge about its biological and pharmacological properties.View study
2024[6]
“Crystagen (immune/thymus peptide bioregulator) manufacturer usage instructions”Finding: Synthetic Cytogen capsules contain 10 mg of active peptides (200-400 mcg active peptide per dose). Commonly used in practice at 1-2 capsules once or twice daily with meals; course 10-30 days, repeated every 4-6 months. Not approved as a medicine in Western jurisdictions.View study

Questions

Frequently asked

What makes Crystagen different from Vilon, which also targets immune function?

While both are Khavinson immune bioregulators, they target different aspects of immune function. Crystagen (EDP) primarily stimulates thymic epithelial cells — the stromal cells that create the microenvironment for T-cell development. Vilon (KE) is the most potent thymocyte proliferative agent, directly activating the T-cells themselves through sphingomyelin signaling. Crystagen rejuvenates the thymic infrastructure, while Vilon directly stimulates the immune cells within it. They are often used together for comprehensive thymic restoration.

What was the landmark 266-person clinical study?

Conducted at the St. Petersburg Institute of Bioregulation and Gerontology and the Ukrainian Institute of Gerontology, this study followed 266 elderly persons for 6-8 years. Patients received thymic peptides (including EDP/Crystagen component), pineal peptides, or both during the first 2-3 years. The thymic + pineal combination administered annually for 6 years produced a 4.1-fold mortality reduction (p<0.05). Individual peptide arms showed 1.6-2.1 fold mortality reductions. Additional benefits included 2.0-2.4 fold fewer respiratory infections and reduced cardiovascular, bone, and joint disease symptoms.

How does Crystagen achieve anti-tumor effects?

Crystagen's anti-tumor effects operate through multiple mechanisms: enhanced immune surveillance (improved T-cell function detects and eliminates cancer cells), direct tumor cell inhibition (demonstrated against K-562 human erythroleukemia cells in vitro), and age-rate reduction (slower biological aging reduces cumulative cancer risk). In long-term animal studies, total tumor incidence was reduced 1.5-fold, malignant tumors by 1.7-fold, and hematopoietic malignancies (leukemias/lymphomas) by 3.4-fold.

Was Crystagen used for COVID-19 treatment?

Thymalin, the natural thymic peptide complex that contains the EDP component (Crystagen), was studied for COVID-19 treatment by Khavinson's group. Results showed accelerated decline in pro-inflammatory cytokine IL-6, faster decreases in C-reactive protein and D-dimer (blood clotting marker), and accelerated T-cell system recovery. The mechanism involves enhanced hematopoietic stem cell differentiation and immune restoration, which is critical for COVID-19 patients who experience T-cell depletion.

Why does Crystagen work better in senescent (older) cells?

This is a defining characteristic of geroprotective peptides. In cell culture studies, Crystagen's stimulation of thymic epithelial cell proliferation was most pronounced at later cell passages (passage 7 — representing aged, senescent cells). Similarly, its effects on thymocyte preservation and immune function are more dramatic in aged organisms. This suggests that Crystagen specifically addresses age-related dysregulation rather than simply boosting already-functional systems, making it a true geroprotective agent rather than a general immunostimulant.

What is the safety profile of Crystagen based on available evidence?

Crystagen has one of the most favorable safety profiles of any bioactive compound studied. Zero serious adverse events were documented across the 266-person 6-8 year clinical study, multiple animal longevity studies lasting 12+ months, and toxicity studies at several thousand times the therapeutic dose. Chromosome aberration rates actually decreased by 17.1% in bone marrow of treated animals (confirming no genotoxicity). Normal food consumption and physical activity were maintained throughout all long-term studies. The therapeutic index exceeds 1000x.

Further reading

History & related research

History · since 1990

Synthetic thymus-derived immunomodulator for T-cell normalization and immune system regeneration

CRYSTAGEN is a synthetic tripeptide (Thr-Lys-Asp/TKD) developed by Vladimir Khavinson at the St. Petersburg Institute of Bioregulation and Gerontology.

Read the full history of Crystagen

Ready for the protocol?

Every dosing tier, administration route, timing note, and dose-adjustment rule for Crystagen, on one page.

Medical disclaimer

Crystagen is an investigational research compound not approved by the FDA for human therapeutic use. This information is for educational purposes only and should not be construed as medical advice. Always consult with a qualified healthcare provider before starting any new supplement or treatment protocol.

Last updated: Aug 10, 2026