Peptide Comparison
CrystagenvsThymalin
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
Russian thymic peptide complex that rejuvenates immune function and supports healthy aging
At a Glance
Quick
comparison
Dose Range
Crystagen
1–100 mcg/kg
Thymalin
5–10 mg
Frequency
Crystagen
Once daily
Thymalin
Once daily
Administration
Crystagen
Subcutaneous injection
Thymalin
Intramuscular injection
Cycle Length
Crystagen
8-12 weeks
Thymalin
4-6 weeks
Onset Speed
Crystagen
Gradual (3-4 weeks)
Thymalin
Moderate (1-2 weeks)
Evidence Level
Crystagen
Limited human trials
Thymalin
Limited human trials
Efficacy
Benefit
ratings
Recovery
Anti-aging
Immune
Immune Restoration
Longevity Support
Disease Prevention
Technical Data
Compound
specifications
Crystagen
Molecular Formula
C14H21N3O8
Molecular Weight
359.3 g/mol
Half-Life
Short plasma half-life typical of tripeptides (minutes); biological effects persist for weeks to months through gene expression modifications and thymic microenvironment restoration; metabolized to constituent amino acids
Bioavailability
Absorbed via intestinal peptide transporters (PepT1/POT and LAT carrier families) when administered orally; rapid absorption from subcutaneous injection sites; efficient cellular uptake due to ultra-short tripeptide structure
CAS Number
Not assigned (patented as immunogeroprotective peptide, US8057810B2)
Thymalin
Molecular Formula
Complex mixture; active dipeptide EW: C16H19N3O5
Molecular Weight
Polypeptide complex; components 250-1000 Da; active dipeptide EW ~321 Da
Half-Life
Not precisely characterized for complex; immune effects persist weeks post-administration
Bioavailability
High via intramuscular or subcutaneous injection
CAS Number
63958-90-7
Protocols
Dosing
tiers
Crystagen
Thymalin
Applications
Best
suited for
Crystagen
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.
Thymalin
Aging Adults Seeking Immune Support
Thymalin is especially valuable for people over 55 whose thymus gland has naturally shrunk with age. By stimulating thymic function, it helps restore the immune training center that your body relies on to fight infections and stay healthy.
Longevity and Anti-Aging Protocols
Clinical studies tracking patients for 6-8 years showed Thymalin reduced mortality by 2.0-2.1-fold. Combined with Epitalon, the mortality reduction reached an impressive 4.1-fold, making this combination one of the most studied longevity peptide protocols.
Seasonal Illness Prevention
Research shows Thymalin cuts respiratory infection rates by 2.0-2.4-fold. A short 10-day course before cold and flu season can significantly boost your immune defenses for months afterward.
Safety Profile
Side
effects
Crystagen
Common
- Injection site reaction
- Mild fatigue
- Mild headache
- Minor digestive changes
Uncommon
- Flu-like symptoms
Serious
- No documented serious adverse effects
Thymalin
Common
- No side effects in most patients
- Mild injection site reaction
Uncommon
- Transient low-grade fever
- Mild flu-like symptoms
- Temporary headache
Serious
- Severe allergic reaction
Research Status
Safety
& evidence
Crystagen
Evidence Level
Limited human trials
FDA Status
Research compound
Safety Overview
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.
Contraindications
- xKnown hypersensitivity to peptide bioregulators or constituent amino acids (glutamic acid, aspartic acid, proline)
- xPregnancy and breastfeeding — insufficient reproductive safety data
- xActive autoimmune disease in flare without physician supervision
- xOrgan transplant recipients on immunosuppression — potential interference with immunosuppressive regimens
Thymalin
Evidence Level
Limited human trials
FDA Status
Research compound
Safety Overview
Thymalin has an excellent safety profile based on over 40 years of clinical use in Russia. Most patients experience zero side effects, and the peptide complex has been described as 'practically non-toxic' in research literature. It has been used safely in thousands of patients, including elderly populations over extended periods.
Contraindications
- xActive thymic tumors or malignancies
- xKnown hypersensitivity to animal-derived peptide products
- xPregnancy and breastfeeding (insufficient safety data)
- xSevere uncontrolled autoimmune disease without medical supervision
Decision Guide
Which is
right for you?
Choose Crystagen if...
- Restoring thymic function and immune competence in aging individuals with immune senescence
- Comprehensive Khavinson bioregulator protocols for immune and anti-aging support
- Supporting immune function during and after illness recovery
- Geroprotective immunomodulation to extend healthspan and reduce age-related disease incidence
Choose Thymalin if...
- Immune system restoration in aging adults
- Longevity and healthy aging support
- Reducing infection frequency and severity
- Multi-system health optimization