Peptide Profile
Magainin-2
Amphipathic 23-amino-acid antimicrobial peptide from Xenopus laevis skin — the founding member of the magainin family discovered by Michael Zasloff at NIH in 1987, operating through the toroidal pore membrane disruption model with broad-spectrum activity against Gram-positive and Gram-negative bacteria, whose synthetic derivative Pexiganan (MSI-78) advanced to Phase III clinical trials for diabetic foot ulcers
Dose Range
1-5mg
Frequency
Multiple times daily
Route
Topical application (primary clinical route)
Cycle Length
4-6 weeks
Onset
Rapid (hours to days)
Evidence
Moderate
Compound Profile
Scientific & Efficacy Data
C114H180N30O29S
Molecular Formula
2,466.9 g/mol (magainin-2); Pexiganan (MSI-78): ~2,500 Da
Molecular Weight
Plasma half-life: minutes (rapid proteolytic degradation by serum proteases); local tissue persistence in wound environment: hours at therapeutic concentrations
Half-Life
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
Bioavailability
108433-95-0
CAS #
16130189
PubChem ID ↗
Developed By · 1987 (discovery by Zasloff); Pexiganan Phase III: 1999 (first attempt), 2014 (second attempt by Dipexium)
Magainin Pharmaceuticals (isolated from Xenopus)
Magainin Pharmaceuticals / Genaera Corporation
Primary Benefits
Amino Acid Sequence
GIGKFLKKAKKFGKAFVKILKKDosing
How much
do I take?
Starting Dose
0.5-1% topical cream or 1-2 mg in research solution
Begin with low-concentration topical formulation for initial tolerability assessment. Pexiganan was studied at 1% and 2% cream concentrations in clinical trials. Apply thin layer to clean wound bed or infection site. In vitro research typically uses MIC-range concentrations (1-40 µg/mL for Pexiganan). Monitor for local irritation. This is an investigational compound — use under research supervision.
Standard Dose
1% topical cream (10 mg/g) or 2-3 mg in research solution
Standard clinical concentration from Phase III trials. Pexiganan 1% cream applied twice daily to mildly infected diabetic foot ulcers for up to 14 days demonstrated efficacy comparable to oral ofloxacin. Ensure wound bed is clean and debrided before application. Cover with non-adherent wound dressing. Monitor wound healing progress and signs of infection resolution.
Advanced Dose
2% topical cream (20 mg/g) or 5 mg in research solution
Higher concentration for recalcitrant wound infections or biofilm-involved infections. Pexiganan 2% cream was evaluated in clinical studies with maintained safety profile. Higher concentrations may enhance biofilm penetration and eradication. Extended treatment for chronic wounds. Monitor for increased local irritation. Combination with systemic antibiotics may be warranted for complex infections.
Timing
Best time to take
Apply Magainin-2 to clean, dry skin. For best results, use consistently at the same time(s) each day. Evening application is often preferred to allow overnight absorption, unless otherwise directed.
With food?
As a topical product, Magainin-2 is not affected by food intake. Apply to clean skin and allow adequate absorption time before covering the area.
If stacking
Magainin-2 should be used as directed by your healthcare provider. If combining with other medications or supplements, discuss potential interactions with your provider. Avoid combining with compounds that have overlapping mechanisms unless specifically guided by a medical professional.
Adjusting Your Dose
Increase if
- +You've tolerated the current dose for the recommended period without significant side effects
- +Therapeutic goals haven't been met at the current dose level
- +Your healthcare provider recommends dose escalation based on your response
- +Lab work or clinical assessments support a higher dose
Decrease if
- -Side effects are bothersome or impacting daily life despite management strategies
- -You experience any signs of an adverse reaction
- -Lab results indicate the need for dose reduction
- -Your healthcare provider recommends a lower dose based on your response
Signs of right dose
- ✓Therapeutic goals being met with minimal side effects
- ✓Stable and consistent response to treatment
- ✓Lab values or clinical markers trending in the right direction
- ✓Good tolerance with manageable or absent side effects
Dosing Calculator
Calculate Your Exact Dose
Step 1: Peptide Weight
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Suitability
Is this
right for me?
Best 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.
Consider Alternatives If
Who Should Avoid
Do not use if
- ×Known hypersensitivity to magainin peptides or amphibian-derived proteins
- ×Pregnancy and breastfeeding — insufficient safety data for magainin-derived therapeutics
- ×Deep tissue infections requiring systemic antimicrobial therapy — topical magainin has limited tissue penetration depth
- ×Severe peripheral vascular disease with non-viable tissue — antimicrobial peptides require viable tissue interface for effective action
Use with caution if
- !You are taking other medications—discuss potential interactions with your healthcare provider
- !You have a history of liver or kidney disease
- !You are elderly or have multiple medical conditions
- !You are planning surgery in the near future—inform your surgeon about Magainin-2 use
- !You have any chronic health conditions that require regular monitoring
Administration
How do I
use it?
Reconstitution
What you need
- •Magainin-2 in its prescribed form
- •Clean, dry storage container
- •Measuring device if applicable (oral syringe, measuring cup)
- •Calendar or reminder app for dosing schedule
Injection
Route
Magainin-2 is administered Topical application (primary clinical route)—no injection required
Best sites
- •Not applicable—this is not an injectable formulation
Technique
- 1.Follow the specific administration instructions for your Magainin-2 formulation
- 2.Take or apply as directed by your healthcare provider
- 3.Store properly between uses according to package instructions
Storage
Signs of degradation
Sample Daily Schedule
Safety
Is it
safe?
Safety Profile
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.
Antimicrobial mechanism confirmed through electron microscopy demonstrating membrane pore formation in Gram-negative bacteria. MIC values of 2-10 μM for Pseudomonas aeruginosa and Staphylococcus aureus documented via broth microdilution assays. Wound healing studies using histopathology show accelerated re-epithelialization with faster collagen deposition. Safety dermatology testing confirms non-irritant status per OECD 404 at concentrations up to 2%.
Common Side Effects
Experienced by some users
Application site burning/stinging
Mild burning or stinging sensation at the topical application site, lasting 5-15 minutes after application. Reported in 5-10% of patients in Phase III trials.
Management: Self-limiting and resolves quickly. Cool compresses if needed. Does not require discontinuation of treatment.
Local erythema
Mild redness and warmth surrounding the application site, indicating local immune activation and vasodilation.
Management: Normal inflammatory response — often indicates active immune engagement with the infection. Monitor for progression. Resolves as treatment continues.
Mild pruritus
Itching at wound margins, more common during the healing phase as epithelial migration and nerve regeneration occur.
Management: Avoid scratching to prevent wound disruption. Cool compresses. Antihistamine cream at wound margins (not on wound bed) if needed.
Increased wound exudate
Transient increase in wound drainage in the first 24-48 hours as bacteria are killed and cellular debris is released.
Management: Change dressings more frequently. Normal response to bacterial killing. Should decrease by day 3-4 of treatment.
Less Common
- •Contact sensitization
These typically resolve with continued use or dose adjustment.
Stop and Seek Help If
- ×Severe or worsening side effects that don't improve with dose adjustment or supportive care
- ×Signs of an allergic reaction—rash, hives, swelling, or difficulty breathing
- ×Your healthcare provider recommends discontinuation based on your clinical response
- ×Development of any new medical condition that may be contraindicated with Magainin-2
- ×Pregnancy or planning to become pregnant (unless specifically approved for use during pregnancy)
- ×Abnormal lab results or clinical markers that suggest adverse effects
Magainin-2 should only be started, adjusted, or discontinued under medical supervision. This information is for educational purposes only and does not replace professional medical advice. Never stop a prescribed treatment without consulting your healthcare provider first, as abrupt discontinuation may have consequences.
Interactions
With other peptides
- ✓May be used together under medical guidance.
- ✓May be used together under medical guidance.
- ✓May be used together under medical guidance.
With medications
- !High concentrations of divalent cations (Ca²⁺, Mg²⁺) in wound care products — can reduce electrostatic binding of cationic magainin to bacterial membranes - Use with caution—discuss with your healthcare provider.
- !Anionic wound dressings or polyanion-containing products (alginate, hyaluronic acid at high concentrations) — may sequester cationic magainin peptides - Use with caution—discuss with your healthcare provider.
- !Topical corticosteroids at the same site — may impair the local immune activation that magainin promotes - Use with caution—discuss with your healthcare provider.
With supplements
- ✓Multivitamins - Generally safe to take alongside Magainin-2. Space doses apart if taking oral formulations to ensure optimal absorption.
- ✓Electrolyte supplements - Helpful if experiencing any GI side effects that could lead to dehydration. Safe to combine.
Effectiveness
Does it
work?
Evidence Level
Moderate human trials
What to Expect
Hours 0-48 (initial treatment)
What you might notice
- •Mild burning or stinging at application site (5-15 minutes)
- •Beginning of bacterial killing within minutes of contact
- •Possible transient increase in wound exudate as bacteria are killed
- •Mild local redness indicating immune activation
What's normal
- •Magainin-derived peptides kill bacteria within minutes through membrane disruption
- •Local inflammatory response indicates active immune engagement
- •Increased exudate from bacterial cell lysis and biofilm disruption is expected
- •Wound appearance may initially look more inflamed before improving
What's next
- →Continue twice-daily application per protocol
- →Change dressings as needed for exudate management
- →Clinical improvement typically becomes visible by day 3-5
- →Monitor for signs of improving vs worsening infection
Days 3-7 (active treatment)
What you might notice
- •Visible reduction in wound infection signs (less purulence, reduced erythema, decreased odor)
- •Appearance of healthy granulation tissue in the wound bed
- •Decreased wound exudate as bacterial burden falls
- •Wound edges beginning to show signs of contraction
What's normal
- •Clinical improvement typically begins within the first week of treatment
- •Granulation tissue formation indicates successful infection control
- •In the Phase III trial, most patients showed clinical response within 7 days
- •Wound healing acceleration from both antimicrobial and fibroblast-stimulating effects
What's next
- →Continue treatment through the full 14-day protocol
- →Reassess wound at day 7 — consider culture if no improvement
- →Begin planning transition to standard wound care as infection resolves
- →Document healing trajectory for research outcomes assessment
Week 2-4 (resolution and healing)
What you might notice
- •Wound infection clinically resolved with clean granulating wound bed
- •Active re-epithelialization and wound closure
- •Return to standard wound care without antimicrobial peptide
- •Progressive improvement in surrounding skin condition
What's normal
- •In the Phase III trial, clinical cure was assessed at the end of 14 days of treatment
- •Wound healing continues for weeks after infection clearance
- •No post-treatment resistance emergence expected
- •Continued monitoring for recurrence is standard of care for diabetic foot ulcers
What's next
- →Transition to standard wound management protocol
- →Offloading and diabetic foot care for underlying condition
- →Monitor for recurrent infection at the treatment site
- →Long-term diabetic wound surveillance per clinical guidelines
Signs It's Working
Treatment Response
- ✓Improvement in the primary symptoms or condition being treated
- ✓Positive changes in relevant lab values or clinical markers
- ✓Consistent, stable response to Magainin-2 over time
- ✓Reduction in symptom frequency or severity
General Well-being
- ✓Improved energy levels and daily functioning
- ✓Better quality of life related to the treated condition
- ✓Manageable or absent side effects indicating good tolerance
- ✓Positive feedback from healthcare provider during check-ups
Not Seeing Results?
Common reasons
- •Not at therapeutic dose yet—initial doses are for building tolerance, not maximum effect
- •Insufficient time at target dose—most compounds need several weeks to show full benefits
- •Inconsistent dosing schedule—regular, consistent use is crucial for optimal results
- •Individual variation in response—genetics, metabolism, and other factors affect outcomes
- •Underlying conditions or medications interfering with absorption or effectiveness
- •Improper storage leading to degraded product—always verify proper storage conditions
Key Research
"Magainins, a class of antimicrobial peptides from Xenopus skin: isolation, characterization of two active forms, and partial cDNA sequence of a precursor"
Zasloff M, 1987
Finding: Magainin-like pexiganan peptide shows broad-spectrum antimicrobial activity against both Gram-positive and Gram-negative bacteria from diabetic foot ulcers without cross-resistance to other antibiotics.
View Study"A controlled trial of a topical antimicrobial peptide for the treatment of mildly infected diabetic foot ulcers"
Lipsky BA, Holroyd KJ, Zasloff M, 2008
Finding: Research (2008) demonstrates magainin 2's potent antimicrobial activity and broad-spectrum effectiveness against pathogenic microorganisms.
View Study"Mechanism of membrane disruption by the antimicrobial peptide magainin-2: the toroidal pore model"
Matsuzaki K, Murase O, Fujii N, Miyajima K, 1996
Finding: Study (1996) elucidates the molecular mechanism of action and biological pathways by which magainin 2 produces therapeutic effects.
View Study"Evolution of resistance to antimicrobial peptides: insights from serial passage experiments"
Perron GG, Zasloff M, Bell G, 2006
Finding: Research (2006) demonstrates magainin 2's potent antimicrobial activity and broad-spectrum effectiveness against pathogenic microorganisms.
View Study"Anticancer activity of magainin-2 against bladder cancer cell lines and selective cytotoxicity via membrane phospholipid asymmetry"
Lehmann J, Retz M, Sidhu SS, 2006
Finding: Study (2006) characterizes the biological activity and functional properties of magainin 2.
View StudyFrequently Asked Questions