Peptide Comparison
Lactoferricin BvsCathelicidin (hCAP-18 / Synthetic Derivatives)
A 25-amino-acid antimicrobial peptide fragment derived from bovine lactoferrin by pepsin cleavage, featuring a twisted antiparallel beta-sheet structure with broad-spectrum bactericidal activity, anti-biofilm properties, and emerging anticancer potential through selective membrane disruption mediated by the critical RRWQWR motif
Human cationic antimicrobial protein-18 (hCAP-18) precursor and its synthetic derivative SAAP-148 — a next-generation 24-amino-acid cathelicidin-based peptide with broad-spectrum bactericidal activity against multidrug-resistant ESKAPE pathogens including MRSA biofilms, superior potency to its parent fragment LL-37, and retained efficacy under physiological salt and plasma conditions
At a Glance
Quick
comparison
Dose Range
Lactoferricin B
1–10 mg
Cathelicidin (hCAP-18 / Synthetic Derivatives)
0.5–5 mg
Frequency
Lactoferricin B
Multiple times daily
Cathelicidin (hCAP-18 / Synthetic Derivatives)
Once daily
Administration
Lactoferricin B
Oral (research — resistant to gastric digestion)
Cathelicidin (hCAP-18 / Synthetic Derivatives)
Topical application (primary research route)
Cycle Length
Lactoferricin B
4-6 weeks
Cathelicidin (hCAP-18 / Synthetic Derivatives)
4-6 weeks
Onset Speed
Lactoferricin B
Rapid (hours to days)
Cathelicidin (hCAP-18 / Synthetic Derivatives)
Rapid (hours to days)
Evidence Level
Lactoferricin B
Moderate human trials (Phase 1-2)
Cathelicidin (hCAP-18 / Synthetic Derivatives)
Moderate human trials (Phase 1-2)
Efficacy
Benefit
ratings
Fighting Germs
Cancer Cell Targeting
Immune Support
Antibiotic-Resistant Infections
Biofilm Destruction
Immune System Support
Technical Data
Compound
specifications
Lactoferricin B
Molecular Formula
Approximately C142H224N46O34S2 (varies slightly by reported sequence)
Molecular Weight
~3,126 Da (25-amino-acid bovine lactoferricin B)
Half-Life
Plasma half-life: minutes (proteolytic degradation); gastrointestinal persistence: hours (relative resistance to trypsin and chymotrypsin compared to unstructured peptides); beta-sheet structure and disulfide bond provide moderate protease resistance
Bioavailability
Generated endogenously during gastric digestion of dietary lactoferrin; partially resistant to further proteolytic degradation due to beta-sheet structure and disulfide bond; systemic bioavailability limited by intestinal proteases and hepatic metabolism
CAS Number
146897-68-9
Cathelicidin (hCAP-18 / Synthetic Derivatives)
Molecular Formula
hCAP-18: ~18 kDa precursor protein (170 AA); SAAP-148: C155H253N49O31 (approximate), MW 3,267.1 Da
Molecular Weight
hCAP-18 precursor: ~18,000 Da; SAAP-148: 3,267.1 Da; OP-145: ~2,900 Da
Half-Life
Plasma half-life: minutes (proteolytic degradation); local tissue persistence: hours at therapeutic concentrations in wound environment; enhanced stability compared to LL-37 due to N-terminal acetylation and C-terminal amidation
Bioavailability
Topical bioavailability optimized in hypromellose ointment formulations; SAAP-148 retains activity in human plasma unlike LL-37; systemic bioavailability limited by proteolytic degradation
CAS Number
Not assigned (SAAP-148 and OP-145 are novel synthetic derivatives)
Protocols
Dosing
tiers
Lactoferricin B
Cathelicidin (hCAP-18 / Synthetic Derivatives)
Applications
Best
suited for
Lactoferricin B
Research into dairy-derived antimicrobial peptides and natural innate defense mechanisms
Lactoferricin B is particularly well-suited for individuals focused on research into dairy-derived antimicrobial peptides and natural innate defense mechanisms. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Investigation of structure-activity relationships in beta-sheet antimicrobial peptides
Lactoferricin B is particularly well-suited for individuals focused on investigation of structure-activity relationships in beta-sheet antimicrobial peptides. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Preclinical development of anticancer peptides targeting membrane phospholipid asymmetry
Lactoferricin B is particularly well-suited for individuals focused on preclinical development of anticancer peptides targeting membrane phospholipid asymmetry. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Understanding the gastrointestinal antimicrobial defense provided by dietary lactoferrin digestion
Lactoferricin B is particularly well-suited for individuals focused on understanding the gastrointestinal antimicrobial defense provided by dietary lactoferrin digestion. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Cathelicidin (hCAP-18 / Synthetic Derivatives)
Research into next-generation antimicrobials against multidrug-resistant infections
Cathelicidin (hCAP-18 / Synthetic Derivatives) is particularly well-suited for individuals focused on research into next-generation antimicrobials against multidrug-resistant infections. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Topical antimicrobial development for wound infections with biofilm involvement
Cathelicidin (hCAP-18 / Synthetic Derivatives) is particularly well-suited for individuals focused on topical antimicrobial development for wound infections with biofilm involvement. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Understanding vitamin D-cathelicidin innate immune axis for immune optimization
Cathelicidin (hCAP-18 / Synthetic Derivatives) is particularly well-suited for individuals focused on understanding vitamin d-cathelicidin innate immune axis for immune optimization. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Development of anti-biofilm therapeutics for chronic device-related and wound infections
Cathelicidin (hCAP-18 / Synthetic Derivatives) is particularly well-suited for individuals focused on development of anti-biofilm therapeutics for chronic device-related and wound infections. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Safety Profile
Side
effects
Lactoferricin B
Common
- Mild GI discomfort
- Bitter taste
- Local irritation (topical use)
- Mild flatulence
Uncommon
- Allergic reaction in milk-sensitive individuals
Serious
- Hemolytic activity at high concentrations
Cathelicidin (hCAP-18 / Synthetic Derivatives)
Common
- Local application site irritation
- Local inflammatory response
- Mild wound exudate increase
Uncommon
- Localized urticaria
- Transient pain at injection site
Serious
- Hemolytic activity at supratherapeutic doses
Research Status
Safety
& evidence
Lactoferricin B
Evidence Level
Moderate human trials (Phase 1-2)
FDA Status
Research compound
Safety Overview
Lactoferricin B is a 25-amino acid peptide fragment of human lactoferrin with a well-documented natural history—derived from a dietary protein that humans consume in breast milk and dairy products. Preclinical studies show excellent tolerability with no hepatotoxicity, nephrotoxicity, or genotoxicity in animal models even at supraphysiological doses. The antimicrobial and antifungal mechanism (iron sequestration and membrane disruption) appears selective for pathogenic microorganisms with minimal effect on commensal bacteria at therapeutic concentrations.
Contraindications
- xKnown allergy to bovine milk proteins or lactoferrin — cross-reactivity possible
- xPregnancy and breastfeeding — insufficient safety data for therapeutic-dose lactoferricin supplementation
- xActive hemolytic conditions — at higher concentrations lactoferricin shows some hemolytic activity that may worsen hemolysis
- xIron overload conditions (hemochromatosis) — lactoferricin retains some iron-binding capacity from the parent lactoferrin molecule
Cathelicidin (hCAP-18 / Synthetic Derivatives)
Evidence Level
Moderate human trials (Phase 1-2)
FDA Status
Research compound
Safety Overview
Cathelicidin peptides (natural and synthetic) are not FDA-approved and have no completed human clinical trials. Animal studies demonstrate broad-spectrum antimicrobial activity without systemic toxicity at therapeutic concentrations. However, concern exists regarding immunological tolerance—cathelicidin derivatives can trigger innate immune activation and inflammatory responses at high concentrations. The peptide's mechanism on immune cells is incompletely understood in humans, and effects on chronic immune signaling, tolerance development, or off-target immune activation remain uncharacterized. Bacterial resistance development to cathelicidin-based therapeutics is theoretically possible but not yet documented clinically.
Contraindications
- xKnown hypersensitivity to cathelicidin-derived peptides or formulation components
- xPregnancy and breastfeeding — insufficient reproductive safety data for synthetic derivatives
- xActive autoimmune conditions involving cathelicidin dysregulation (e.g., rosacea, psoriasis) — exogenous cathelicidin peptides may exacerbate inflammation
- xSevere systemic immunodeficiency without medical supervision — immune modulation effects may be unpredictable
Decision Guide
Which is
right for you?
Choose Lactoferricin B if...
- Research into dairy-derived antimicrobial peptides and natural innate defense mechanisms
- Investigation of structure-activity relationships in beta-sheet antimicrobial peptides
- Preclinical development of anticancer peptides targeting membrane phospholipid asymmetry
- Understanding the gastrointestinal antimicrobial defense provided by dietary lactoferrin digestion
Choose Cathelicidin (hCAP-18 / Synthetic Derivatives) if...
- Research into next-generation antimicrobials against multidrug-resistant infections
- Topical antimicrobial development for wound infections with biofilm involvement
- Understanding vitamin D-cathelicidin innate immune axis for immune optimization
- Development of anti-biofilm therapeutics for chronic device-related and wound infections