LL-37 for Skin: What the Evidence Shows
What human and animal studies show about LL-37 for skin, how strong that evidence is, and what is still unproven.
- Strongest evidence
- Human RCT
- Human studies
- 3
- with an outcome for skin, in our evidence file (PubMed search, 11 Oct 2026)
- Animal studies
- 2
- with an outcome for skin, in our evidence file (PubMed search, 11 Oct 2026)
- Studies we summarised
- 5
- with an outcome for skin
Evidence for skin
Each row is an outcome related to skin from a published study, strongest design first. Animal and cell results are labelled and are not human results. User reports are not counted as evidence here.
| Outcome | Result | Study type | Source |
|---|---|---|---|
| Granulation index | Granulation index rose more in the LL-37 cream group than placebo on days 7, 14, 21 and 28 (p = 0.031, 0.009, 0.006, 0.037). | Human RCT | Archives of dermatological research 2023, PMID 37480520 |
| Healing, whole study population | No significant improvement in healing with LL-37 versus placebo in the full population (primary analysis). | Human RCTn = 148 | Wound repair and regeneration 2021, PMID 34687253 |
| Healing, large-wound subgroup (post hoc) | A post hoc subgroup analysis (wounds of at least 10 cm2) showed improvement in several healing parameters; hypothesis-generating only. | Human RCTn = 148 | Wound repair and regeneration 2021, PMID 34687253 |
| Ulcer healing rate (lower doses) | Healing rate constants were approximately six-fold (0.5 mg/mL, p = 0.003) and three-fold (1.6 mg/mL, p = 0.088) higher than placebo. | Human RCTn = 34 | Wound repair and regeneration 2014, PMID 25041740 |
| Ulcer area reduction | Mean ulcer area decreased 68% (0.5 mg/mL) and 50% (1.6 mg/mL). | Human RCTn = 34 | Wound repair and regeneration 2014, PMID 25041740 |
| Pressure ulcer area | LL-37 in chitosan hydrogel promoted healing of pressure ulcers in mice (formulation study, not free peptide alone). | Animal · mouse (not a human result)n = 6 | Military Medical Research 2020, PMID 32321591 |
| Wound healing | Nanoparticle-delivered LL37 accelerated wound healing compared with PLGA or LL37 alone (formulation study). | Animal · (species not stated in abstract) (not a human result) | Journal of controlled release 2014, PMID 25173841 |
LL-37 and skin are not in our PubMed count ledger yet; the rows above come from our evidence file (PubMed search, 11 Oct 2026). Grades follow our .
How strong is it?
A human randomized trial outweighs any number of animal studies. Animal and cell results show a mechanism worth testing, not that it works in people.
Skin ageing in plain terms
MedlinePlus says skin thins and loses fat with age and may take longer to heal.[6]
Human trials: skin ulcers, not cosmetic skin
The first-in-man trial gave twice-weekly topical LL-37 (0.5, 1.6 or 3.2 mg/mL) or placebo to 34 people with venous leg ulcers for 4 weeks of randomised treatment; the two lower doses markedly decreased the mean ulcer area (68% and 50%) but 3.2 mg/mL did not differ from placebo.[3]
In the larger phase IIb trial, LL-37 did not significantly improve healing versus placebo across the whole study group.[2]
A post hoc subgroup analysis found improvement in patients whose wounds were at least 10 cm2 at randomisation, which the authors say needs a properly powered study.[2]
In a double-blind trial of LL-37 cream on diabetic foot ulcers with mild infection, the increase in granulation index was greater with LL-37 on days 7, 14, 21 and 28.[1]
Animal wound models
In mouse full-thickness excisional wounds, LL37 loaded into PLGA nanoparticles accelerated healing compared with LL37 alone, an animal result.[5]
Other peptides people research for skin
All peptides for skin, comparedCommon questions
Does LL-37 help with skin?
The strongest study we summarise for skin is human rct evidence, across 5 studies with an outcome for skin. A trial result is not an approval; see the legal status.
Is LL-37 approved for skin?
No. LL-37 is not FDA approved for any use, including skin.
What is the best peptide for skin?
There is no single answer. Our skin overview compares each candidate by evidence grade and legal status rather than by popularity.
Does LL-37 help skin?
The human trials were in chronic leg and foot ulcers; the larger phase IIb trial found no significant overall improvement versus placebo.[2]
Is LL-37 cream proven?
A diabetic foot ulcer trial reported that LL-37 cream enhanced the healing rate, while not decreasing IL-1 alpha, TNF-alpha or bacterial colonisation.[1]
More on LL-37
Sources
- 1Efficacy of LL-37 cream in enhancing healing of diabetic foot ulcer: a randomized double-blind controlled trial.Archives of dermatological research · 2023PMID 37480520Accessed 2 Oct 2026
- 2Evaluation of LL-37 in healing of hard-to-heal venous leg ulcers: A multicentric prospective randomized placebo-controlled clinical trial.Wound repair and regeneration : official publication of the Wound Healing Society [and] the European Tissue Repair Society · 2021PMID 34687253Accessed 2 Oct 2026
- 3Treatment with LL-37 is safe and effective in enhancing healing of hard-to-heal venous leg ulcers: a randomized, placebo-controlled clinical trial.Wound repair and regeneration : official publication of the Wound Healing Society [and] the European Tissue Repair Society · 2014PMID 25041740Accessed 2 Oct 2026
- 4Chitosan hydrogel encapsulated with LL-37 peptide promotes deep tissue injury healing in a mouse model.Military Medical Research · 2020PMID 32321591Accessed 2 Oct 2026
- 5PLGA nanoparticles loaded with host defense peptide LL37 promote wound healing.Journal of controlled release : official journal of the Controlled Release Society · 2014PMID 25173841Accessed 2 Oct 2026
- 6Official web pageOfficial web page · web page
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