Magainin-2 vs LL-37 — Peptide Comparison

For education only

This guide cannot diagnose a condition or recommend a personal treatment plan. Discuss medical questions with a qualified professional.

At a Glance

Quickcomparison

Dose Range

Magainin-2

1–5 mg

LL-37

0.5–1.6 mg/mL (topical)

Frequency

Multiple times daily

Once daily

Administration

Topical application (primary clinical route)

Topical application (wound healing)

Cycle Length

4-6 weeks

12+ weeks

Onset Speed

Rapid (hours to days)

Moderate (1-2 weeks)

Evidence Level

Moderate human trials (Phase 1-2)

Efficacy

Benefitratings

Fighting Infections

Resistance Prevention

Wound Healing

Immune Boost

Technical Data

Compoundspecifications

Molecular Formula

C114H180N30O29S

Molecular Weight

2,466.9 g/mol (magainin-2); Pexiganan (MSI-78): ~2,500 Da

Half-Life

Plasma half-life: minutes (rapid proteolytic degradation by serum proteases); local tissue persistence in wound environment: hours at therapeutic concentrations

Bioavailability

Topical bioavailability: local tissue concentrations achieve bactericidal levels with 1-2% cream formulation; systemic bioavailability minimal — rapidly degraded by tissue proteases if absorbed; poor oral bioavailability

CAS Number

108433-95-0

C205H340N60O53

4,493.26 Da

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

Topical application achieves high local wound-bed concentrations; systemic bioavailability limited by rapid proteolytic degradation and serum protein binding; not intended for oral delivery

154947-66-7

Protocols

Dosingtiers

standard

1% cream (pexiganan, a magainin-2 analog)

Twice daily

Up to 28 days

Pexiganan (MSI-78), a synthetic magainin-2 analog, was tested as a 1% topical cream in Phase 3 diabetic foot-ulcer trials and matched oral ofloxacin for clinical improvement (~85-90%) [6]. Native magainin-2 itself has no approved human dosing; figures reflect its clinical-stage analog.

starting

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

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].

Applications

Bestsuited for

Research into topical antimicrobial peptides for diabetic foot ulcer management

Magainin-2 is particularly well-suited for individuals focused on research into topical antimicrobial peptides for diabetic foot ulcer management. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.

Understanding the toroidal pore model of antimicrobial peptide membrane disruption

Magainin-2 is particularly well-suited for individuals focused on understanding the toroidal pore model of antimicrobial peptide membrane disruption. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.

Development of resistance-proof antimicrobial agents targeting membrane architecture

Magainin-2 is particularly well-suited for individuals focused on development of resistance-proof antimicrobial agents targeting membrane architecture. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.

Investigation of selective anticancer activity mediated by membrane phospholipid asymmetry

Magainin-2 is particularly well-suited for individuals focused on investigation of selective anticancer activity mediated by membrane phospholipid asymmetry. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.

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.

Safety Profile

Sideeffects

Common

Application site burning/stinging

Local erythema

Mild pruritus

Increased wound exudate

Uncommon

Contact sensitization

Serious

No serious systemic adverse effects documented

Local site irritation

Transient stinging or burning

Mild perilesional erythema

Allergic contact reaction

Hemolytic activity at systemic concentrations

Research Status

Safety& evidence

FDA Status

Research compound

Safety Overview

Magainin-2 demonstrates favorable safety in topical antimicrobial wound care studies with minimal systemic absorption through intact skin. Local tissue irritation minimal at therapeutic concentrations (0.1-1% w/w); hemolytic activity negligible at concentrations <10 μM. No serious adverse events in Phase II wound healing trials. Peptide stability dependent on formulation pH; activity preserved at physiologic pH. Resistance development slower than traditional antibiotics.

Contraindications

xKnown hypersensitivity to magainin peptides or amphibian-derived proteins

xPregnancy and breastfeeding — insufficient safety data for magainin-derived therapeutics

xDeep tissue infections requiring systemic antimicrobial therapy — topical magainin has limited tissue penetration depth

xSevere peripheral vascular disease with non-viable tissue — antimicrobial peptides require viable tissue interface for effective action

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.

xKnown hypersensitivity to cathelicidin peptides or formulation components

xActive hemolytic conditions — LL-37 demonstrates concentration-dependent hemolytic activity

xPregnancy and breastfeeding — insufficient reproductive safety data from clinical trials

xSevere renal impairment — peptide clearance may be altered

Decision Guide

Which isright for you?

Choose Magainin-2 if...