Peptide data sheet
LL-37
Recovery · Cathelicidin · hCAP-18 · CAMP
Verdict
unprovenThe unproven label reflects a genuinely double-edged evidence base: LL-37 has a large body of laboratory work on killing microbes, shaping immune responses, and supporting wound repair, but controlled human trials establishing a therapeutic benefit are minimal, and the same peptide has been implicated in inflammatory skin disease, so the honest read is interesting-but-unsettled rather than a green light.
Quick answer
LL-37 is the only known human cathelicidin, a 37-amino-acid host-defense peptide cleaved from the hCAP-18 protein and released by neutrophils, skin cells, and other tissues. It is commonly researched for antimicrobial activity against bacteria and biofilms, for immune-signaling roles, and for wound healing. The evidence is largely preclinical, and LL-37 is notably context-dependent: the same peptide is studied both for healing and as a driver of inflammatory skin conditions. It is not FDA-approved and is sold for research use only.
- Class
- Cationic antimicrobial host-defense peptide; sole human cathelicidin (cleaved from hCAP-18, CAMP gene)
- Half-life
- short; rapidly bound and degraded in tissue, not well characterized in humans (reported)
- FDA status
- Not FDA-approved. Studied in preclinical and early research; sold for laboratory research use only, not for human use.
- WADA banned?
- No
Which form actually works?
Topical / wound context
Unproven
The direction with the most host-defense and wound-repair literature behind it, since LL-37 is naturally active in skin and mucosal surfaces. Interest is real, but controlled human data for a topical wound-healing benefit is thin, and because LL-37 is also implicated in inflammatory skin disease the same route carries a genuine two-sided-effect caveat.
Injectable / systemic
Unproven
The systemic-research direction people ask about, based mostly on cell and animal work on antimicrobial and immune-modulating activity. Human data for a systemic benefit is essentially absent, and LL-37's context-dependent, sometimes pro-inflammatory behavior makes this the least-characterized and most uncertain route, so it stays firmly unproven.