LL-37 vs Vilon
Human cathelicidin-derived antimicrobial peptide (37 amino acids) that disrupts bacterial membranes at MIC 0.62 μM against S. aureus, neutralizes endotoxin (LPS) to prevent septic shock, and has reached Phase II clinical trials as Ropocamptide for wound healing — achieving 6-fold accelerated healing at 0.5 mg/mL in venous leg ulcers
Immunomodulatory dipeptide bioregulator (Lys-Glu) that upregulates SIRT1 expression 6-fold through direct DNA promoter binding, activates T-cell differentiation via sphingomyelin signaling, and reduces pro-inflammatory cytokines by up to 6-fold as a natural inducer of TNF tolerance
Written by Michael Carroll — Owner, Director of Research · Reviewed by the Peptide Initiative Research Team · Editorial standards
Quick comparison
Dose range
LL-37
1.6–1.6 mg/mL
Vilon
500–500 mcg
Frequency
LL-37
Once daily
Vilon
Once daily
Administration
LL-37
Topical application (wound healing)
Vilon
Subcutaneous injection
Cycle length
LL-37
12+ weeks
Vilon
12+ weeks
Onset speed
LL-37
Moderate (1-2 weeks)
Vilon
Gradual (3-4 weeks)
Evidence level
LL-37
Moderate human trials (Phase 1-2)
Vilon
Limited human trials
Benefit ratings
Wound Healing
Fighting Infections
Immune Boost
Immune System Revival
Healthy Aging
Digestive Support
Compound specifications
LL-37
Molecular formula
C205H340N60O53
Molecular weight
4,493.26 Da
Half-life
Short systemic half-life (minutes) due to protease susceptibility; local tissue persistence at wound sites is longer due to binding to extracellular matrix components and lipid membranes
Bioavailability
Topical application achieves high local wound-bed concentrations; systemic bioavailability limited by rapid proteolytic degradation and serum protein binding; not intended for oral delivery
CAS number
154947-66-7
Vilon
Molecular formula
C11H21N3O5
Molecular weight
275.3 g/mol
Half-life
Short plasma half-life typical of dipeptides (minutes); biological effects persist for weeks to months through epigenetic modifications to SIRT1/PARP gene expression; metabolized to constituent amino acids
Bioavailability
Absorbed via intestinal peptide transporters (PepT1) when administered orally (demonstrated in animal studies); rapid absorption from subcutaneous injection sites; efficient cellular uptake and nuclear penetration due to ultra-short dipeptide structure
CAS number
45234-02-4
Dosing compared
LL-37
Topical
0.5 mg/mL gel
Twice weekly · 4 weeks
Lowest dose in the LL-37 (ropocamptide) Phase I/IIa venous leg-ulcer trial and the most effective: ~6-fold faster healing and ~68% ulcer-area reduction vs placebo, applied to the wound twice weekly [4].
1.6 mg/mL gel
Twice weekly · 4 weeks
Mid dose in the same trial; ~3-fold improvement and ~50% area reduction vs placebo. The highest tested concentration (3.2 mg/mL) showed no benefit over placebo, so dose escalation above this is not supported [4].
Vilon
Subcutaneous injection
200–500 mcg
Once daily · 5–10 day course
Common Khavinson-style introductory protocol for the KE (Lys-Glu) immune bioregulator; courses repeated 2–3 times yearly [6]. Research use only — no approved product.
500 mcg
Once daily · 10–12 day course
Typical full-course practice dose; cycle repeated every 3–6 months [6].
Intramuscular injection
500 mcg
Once daily · 10–12 day course
Intramuscular delivery is also documented for the injectable KE bioregulator; same per-course dosing as subcutaneous [6].
Best suited for
LL-37
Treatment of chronic non-healing wounds including venous leg ulcers and diabetic ulcers
LL-37 is particularly well-suited for individuals focused on treatment of chronic non-healing wounds including venous leg ulcers and diabetic ulcers. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Immune defense against antibiotic-resistant bacterial infections (MRSA, Pseudomonas)
LL-37 is particularly well-suited for individuals focused on immune defense against antibiotic-resistant bacterial infections (mrsa, pseudomonas). Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Anti-biofilm strategies for chronic wound infections and medical device-associated infections
LL-37 is particularly well-suited for individuals focused on anti-biofilm strategies for chronic wound infections and medical device-associated infections. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Boosting innate immune defense in immunocompromised or aging individuals
LL-37 is particularly well-suited for individuals focused on boosting innate immune defense in immunocompromised or aging individuals. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Vilon
Immune system restoration in aging individuals with declining thymic function
Vilon is particularly well-suited for individuals focused on immune system restoration in aging individuals with declining thymic function. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Adjunctive immunomodulatory support during cancer treatment protocols
Vilon is particularly well-suited for individuals focused on adjunctive immunomodulatory support during cancer treatment protocols. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Geroprotective therapy targeting SIRT1/PARP pathways for cellular longevity
Vilon is particularly well-suited for individuals focused on geroprotective therapy targeting sirt1/parp pathways for cellular longevity. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Comprehensive Khavinson bioregulator protocols for anti-aging and immune support
Vilon is particularly well-suited for individuals focused on comprehensive khavinson bioregulator protocols for anti-aging and immune support. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Side effects
LL-37
Common
- Local site irritation
- Transient stinging or burning
- Mild perilesional erythema
- Increased wound exudate
Uncommon
- Allergic contact reaction
Serious
- Hemolytic activity at systemic concentrations
Vilon
Common
- Injection site reaction
- Mild fatigue
- Mild headache
- Digestive changes
Uncommon
- Flu-like symptoms
Serious
- No documented serious adverse effects
Safety & evidence
LL-37
Evidence level
Moderate human trials (Phase 1-2)
FDA status
Research compound
Safety overview
LL-37 is an endogenous cathelicidin antimicrobial peptide naturally produced by immune cells and epithelial tissues, conferring inherent biocompatibility and low toxicity at physiological concentrations. Synthetic LL-37 shows excellent safety in in vitro immune assays and animal models with no hepatotoxicity, nephrotoxicity, or genotoxicity at relevant doses. At elevated concentrations, the cationic amphipathic structure can cause hemolysis and cell membrane damage, but therapeutic doses are far below these thresholds. Injection site reactions are minimal in research applications.
Contraindications
- Known hypersensitivity to cathelicidin peptides or formulation components
- Active hemolytic conditions — LL-37 demonstrates concentration-dependent hemolytic activity
- Pregnancy and breastfeeding — insufficient reproductive safety data from clinical trials
- Severe renal impairment — peptide clearance may be altered
Vilon
Evidence level
Limited human trials
FDA status
Research compound
Safety overview
Vilon (immunomodulatory thymic peptide complex from bovine thymus) demonstrates favorable safety in Russian/Eastern European medical use over 20+ years with minimal documented serious adverse events in published literature. Bovine-derived peptide preparations carry theoretical prion disease risk (variant Creutzfeldt-Jakob disease) though processing methods and regulatory standards substantially reduce this risk. Common adverse effects are mild—local injection site reactions, transient fever, or lymphadenopathy—consistent with immune system stimulation rather than toxicity.
Contraindications
- Known hypersensitivity to peptide bioregulators or constituent amino acids (lysine, glutamic acid)
- Pregnancy and breastfeeding — insufficient reproductive safety data
- Active autoimmune disease in flare without medical supervision
- Organ transplant recipients on immunosuppression — potential interference with immunosuppressive regimens
Which is right for you?
Choose LL-37 if...
- Treatment of chronic non-healing wounds including venous leg ulcers and diabetic ulcers
- Immune defense against antibiotic-resistant bacterial infections (MRSA, Pseudomonas)
- Anti-biofilm strategies for chronic wound infections and medical device-associated infections
- Boosting innate immune defense in immunocompromised or aging individuals
Choose Vilon if...
- Immune system restoration in aging individuals with declining thymic function
- Adjunctive immunomodulatory support during cancer treatment protocols
- Geroprotective therapy targeting SIRT1/PARP pathways for cellular longevity
- Comprehensive Khavinson bioregulator protocols for anti-aging and immune support