Immune & AutoimmuneModerate: well-characterized mechanism

LL-37 (Cathelicidin) Peptide Therapy

Benefits, Side Effects, Cost & Protocols

Also known as: Cathelicidin LL-37

LL-37 (Cathelicidin) peptide molecular structure diagram from PubChem

A human antimicrobial peptide that plays a key role in innate immunity. Provides direct antimicrobial defense and modulates immune cell signaling.

ByChris Riley(CFA)&Alex Evans, PharmD, MBA(PharmD, MBA)|Updated May 19, 2026

Clinically Reviewed

Reviewed by Alex Evans, PharmD, MBA · Updated May 2026

Evidence-Based

Sourced from FDA, PubMed & ClinicalTrials.gov · View sources

Typical Cost

$150–$350/mo

FDA Status

Research (RFK 2026 reclassification)

Evidence

Moderate: well-characterized mechanism

Who Is LL-37 (Cathelicidin) Best For?

Immune supportAntimicrobial defenseInfection management

LL-37 (Cathelicidin) Compound Data

Molecular Formula

C205H340N60O53

Molecular Weight

4493 g/mol

IUPAC Name

(4S)-5-[[(1S)-5-amino-1-[[(1S,2S)-1-[[2-[[(1S)-5-amino-1-[[(1S)-1-[[(1S)-2-[[(1S)-5-amino-1-[[(1S)-1-[[(1S,2S)-1-[[(1S)-1-[[(1S)-4-amino-1-[[(1S)-1-[[(1S,2S)-1-[[(1S)-5-amino-1-[[(1S)-2-[[(1S)-2-[[(1S)-1-[[(1S)-1-[[(1S)-3-amino-1-[[(1S)-1-[[(1S)-1-[(2S)-2-[[(1S)-1-[[(1S,2R)-1-[[(1S)-3-carboxy-1-[[(1S)-1-carboxy-2-hydroxy-ethyl]carbamoyl]propyl]carbamoyl]-2-hydroxy-propyl]carbamoyl]-4-guanidino-butyl]carbamoyl]pyrrolidine-1-carbonyl]-2-methyl-propyl]carbamoyl]-3-methyl-butyl]carbamoyl]-3-oxo-propyl]carbamoyl]-4-guanidino-butyl]carbamoyl]-3-methyl-butyl]amino]-1-benzyl-2-oxo-ethyl]amino]-1-(carboxymethyl)-2-oxo-ethyl]carbamoyl]pentyl]carbamoyl]-2-methyl-butyl]carbamoyl]-4-guanidino-butyl]carbamoyl]-4-oxo-butyl]carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-butyl]carbamoyl]-4-guanidino-butyl]carbamoyl]pentyl]amino]-1-benzyl-2-oxo-ethyl]carbamoyl]-3-carboxy-propyl]carbamoyl]pentyl]amino]-2-oxo-ethyl]carbamoyl]-2-methyl-butyl]carbamoyl]pentyl]amino]-4-[[(2S)-6-amino-2-[[(2S)-2-[[(2S)-6-amino-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[2-[[(2S)-2-[[(2S)-2-amino-4-methyl-pentanoyl]amino]-4-methyl-pentanoyl]amino]acetyl]amino]-3-carboxy-propanoyl]amino]-3-phenyl-propanoyl]amino]-3-phenyl-propanoyl]amino]-5-guanidino-pentanoyl]amino]hexanoyl]amino]-3-hydroxy-propanoyl]amino]hexanoyl]amino]-5-oxo-pentanoic acid

View full compound on PubChem

LL-37 (Cathelicidin) News

Biophysical and transcriptomic characterization of LL-37-derived antimicrobial peptide targeting multidrug-resistant Escherichia coli and ESKAPE pathogens | Scientific Reports - Nature

Nature · 7 months ago

Cathelicidin LL37-loaded extracellular vesicles from Edwardsiella piscicida promote antibacterial and wound-healing activity - Nature

Nature · 5 months ago

The Human Cathelicidin Antimicrobial Peptide LL-37 as a Potential Treatment for Polymicrobial Infected Wounds - Frontiers

Frontiers · 27 months ago

LL-37: A Multifunctional Host-Defense Peptide in Immunity, Molecular Engineering, and More - Senegal Direct

Senegal Direct · 16 days ago

Human antimicrobial peptide LL-37 induces glial-mediated neuroinflammation - ScienceDirect.com

ScienceDirect.com · 98 months ago

News aggregated via Google News. Inclusion does not imply endorsement.

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Medical Disclaimer: The information on this page is for educational purposes only and does not constitute medical advice. Peptide therapies have not been evaluated by the FDA for most listed indications.All prices shown are estimates based on publicly available data and may not reflect current pricing — providers and brands set their own prices and can change them at any time. Always verify pricing directly with the provider before purchasing. Consult a licensed healthcare provider before starting any peptide protocol.

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