In short
The human cathelicidin antimicrobial peptide. As a topical treatment for leg ulcers, a small first trial looked promising but a larger Phase IIb trial missed its main goal.
Also known ashuman cathelicidin
CategoryImmune
Canada statusNot authorized in Canada
Human evidence Limited: small or low-quality human studies (topical wound trials)
Last reviewedNovember 10, 2026
How strong is the human evidence?
- Cell & animal
- Small human studies
- Some randomized trials
- Large randomized trials
What is LL-37?
LL-37 is part of the body's innate defence against microbes.
Is LL-37 legal in Canada?
Not authorized: no product found in Health Canada's Drug Product Database.
What the research shows
- Grönberg et al. (2014): first-in-human trial, 34 patients with venous leg ulcers; topical LL-37 was safe and some doses improved healing measures.
- Mahlapuu et al. (2021): Phase IIb, 148 patients; no significant improvement in healing vs placebo overall (a post-hoc subgroup with large ulcers did better).
What it doesn't show
- No evidence for injected LL-37 for infections, immunity or cancer.
Common questions
Is LL-37 legal in Canada?
It is not authorized by Health Canada.
Does LL-37 heal wounds?
The larger Phase IIb trial did not show a significant overall benefit.
Sources
- Health Canada Drug Product Database (searched Nov 10, 2026)
- Grönberg A et al. LL-37 for hard-to-heal venous leg ulcers: RCT. Wound Repair Regen 2014
- Mahlapuu M et al. Evaluation of LL-37 in hard-to-heal venous leg ulcers: phase IIb RCT. Wound Repair Regen 2021
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