Peptide Comparison
Defensin (HBD-2)vsThymalin
Inducible human beta-defensin antimicrobial peptide (41 amino acids) that kills bacteria through membrane disruption at MIC 50 μg/mL against S. aureus, recruits dendritic cells and T cells via CCR6 receptor chemotaxis, and serves as a critical bridge between innate and adaptive immunity — upregulated up to 100-fold during infection and inflammation
Russian thymic peptide complex that rejuvenates immune function and supports healthy aging
At a Glance
Quick
comparison
Dose Range
Defensin (HBD-2)
10–100 μg/mL (research)
Thymalin
5–10 mg
Frequency
Defensin (HBD-2)
As needed
Thymalin
Once daily
Administration
Defensin (HBD-2)
Topical application (research/wound care)
Thymalin
Intramuscular injection
Cycle Length
Defensin (HBD-2)
Ongoing/indefinite
Thymalin
4-6 weeks
Onset Speed
Defensin (HBD-2)
Rapid (hours to days)
Thymalin
Moderate (1-2 weeks)
Evidence Level
Defensin (HBD-2)
Moderate human trials (Phase 1-2)
Thymalin
Limited human trials
Efficacy
Benefit
ratings
Healing
Growth
Immune
Immune Restoration
Longevity Support
Disease Prevention
Technical Data
Compound
specifications
Defensin (HBD-2)
Molecular Formula
Approximately C185H290N54O57S6 (41-amino acid peptide with 3 disulfide bonds)
Molecular Weight
~4,328 Da (mature peptide)
Half-Life
Short plasma half-life (minutes); locally stable at wound and epithelial sites due to disulfide-bonded structure; degraded by metalloproteinases in chronic wound environments
Bioavailability
Topical application provides local antimicrobial activity; three disulfide bonds confer resistance to proteolytic degradation; salt-sensitive — activity reduced above 150 mM NaCl; not intended for oral or systemic delivery
CAS Number
Not assigned (endogenous human peptide; research-grade available from multiple suppliers)
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
Defensin (HBD-2)
Thymalin
Applications
Best
suited for
Defensin (HBD-2)
Research into novel topical antimicrobial therapies for skin infections and chronic wounds
Defensin (HBD-2) is particularly well-suited for individuals focused on research into novel topical antimicrobial therapies for skin infections and chronic wounds. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Biomarker development for inflammatory skin disease monitoring (psoriasis, atopic dermatitis)
Defensin (HBD-2) is particularly well-suited for individuals focused on biomarker development for inflammatory skin disease monitoring (psoriasis, atopic dermatitis). Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Understanding innate-adaptive immune crossover mechanisms in mucosal defense
Defensin (HBD-2) is particularly well-suited for individuals focused on understanding innate-adaptive immune crossover mechanisms in mucosal defense. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Development of antimicrobial surfaces and wound dressings incorporating defensin peptides
Defensin (HBD-2) is particularly well-suited for individuals focused on development of antimicrobial surfaces and wound dressings incorporating defensin peptides. 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
Defensin (HBD-2)
Common
- Local site irritation
- Transient inflammatory response
- Reduced activity in saline environments
Uncommon
- Localized allergic reaction
- Inflammatory amplification
Serious
- No serious adverse effects documented
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
Defensin (HBD-2)
Evidence Level
Moderate human trials (Phase 1-2)
FDA Status
Research compound
Safety Overview
Defensin HBD-2 is not FDA-approved and has no completed human clinical trials, with all safety data limited to in vitro mechanistic studies and animal models. Animal toxicology studies show no significant systemic toxicity or organ damage at doses exceeding therapeutic levels. However, human immunological responses to exogenously administered antimicrobial peptides are not fully characterized. Concerns exist regarding potential immune activation, cross-reactivity with self-antigens, and development of antibodies to the synthetic peptide. Bacterial resistance development to defensin-based therapeutics is theoretically possible. No human pharmacokinetics, dose-escalation studies, Phase 1 safety data, or clinical efficacy trials have been conducted.
Contraindications
- xKnown hypersensitivity to defensin peptides or formulation components
- xPregnancy and breastfeeding — insufficient safety data for exogenous defensin administration
- xActive autoimmune skin conditions where defensin overexpression may contribute to pathology (e.g., psoriasis flare)
- xCystic fibrosis patients — elevated airway NaCl concentrations inactivate HBD-2 antimicrobial activity
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 Defensin (HBD-2) if...
- Research into novel topical antimicrobial therapies for skin infections and chronic wounds
- Biomarker development for inflammatory skin disease monitoring (psoriasis, atopic dermatitis)
- Understanding innate-adaptive immune crossover mechanisms in mucosal defense
- Development of antimicrobial surfaces and wound dressings incorporating defensin peptides
Choose Thymalin if...
- Immune system restoration in aging adults
- Longevity and healthy aging support
- Reducing infection frequency and severity
- Multi-system health optimization