SoftMaxx AI sells no peptides and takes no vendor money.
No supporting study We found no peer-reviewed human acne trial of any peptide. KPV rests on cell and mouse studies, LL-37's human studies concern leg ulcers and psoriasis rather than acne, and the one afamelanotide acne trial recruited 3 people; its results are on a trial registry, and we found no journal paper.[1][2][3][4][5]
The tier describes the evidence for any peptide's effect on acne; stronger evidence on this page concerns LL-37 on venous leg ulcers.
The verdict
| Peptide | Best evidence | Acne trial in people? |
|---|---|---|
| KPV | Skin cells [1] and mice (gut inflammation) [2] | None found |
| LL-37 | A leg-ulcer trial; linked to rosacea and psoriasis | None found [3] [6] [7] |
| Afamelanotide | FDA-approved for erythropoietic protoporphyria, a disorder of phototoxic reactions to light [8]; one acne trial, 3 patients, no placebo [5] | Results on a trial registry; we found no journal paper |
None of these has shown an effect on acne in a controlled trial in people that we could find.
- Claim as marketed
KPV clears acne
No supporting study We found no human skin trial of KPV, and FDA has not identified any human exposure data for it.[9][1] - Claim as marketed
LL-37 clears acne
No supporting study We found no acne trial of LL-37.[6][7] - Common belief
Afamelanotide works for acne
Human, small or uncontrolled A phase 2 trial of afamelanotide implants in acne, completed in 2011, recruited only 3 people and had no placebo group. Its results are posted on ClinicalTrials.gov; we found no journal paper.[5]
KPV: cell studies and mice
KPV is a 3-amino-acid fragment (positions 11–13) of alpha-melanocyte-stimulating hormone, alpha-MSH [10].
Its skin evidence comes from cells in a dish [1] [11]. It showed activity against S. aureus and C. albicans in culture, and the abstract does not report testing the main acne bacterium [10].
- In vitro (cells) KPV calmed inflammatory signals in human skin cells grown in a dish.[1][11]
- In vitro (cells) In culture, KPV acted against S. aureus and C. albicans; the abstract does not report testing the acne bacterium C. acnes.[10]
- In vitro (cells) In excised human skin, KPV passing through on its own stayed below the study's detection limit. Microneedles raised delivery, and an electric current on top raised it further.[12]
- Animal The psoriasis study we found tested KdPT, a structurally related but different tripeptide, not KPV.[13]
LL-37: the skin already makes too much
LL-37 is the body's own antimicrobial peptide [7].
Skin biology points the other way. In rosacea, facial skin already holds abnormally high levels of cathelicidin, the protein family LL-37 belongs to, and a mouse study links its rosacea forms to skin inflammation [6].
- Animal People with rosacea have abnormally high levels of cathelicidin in their facial skin, in processed forms that differ from normal skin. In mice, injecting the cathelicidin peptides found in rosacea increased skin inflammation.[6]
- Human observational Studies identify LL-37 as a trigger of immune activation in psoriasis, and found T cells that target it in two-thirds of patients with moderate-to-severe psoriasis.[7][4]
- Human RCT In a 148-patient placebo-controlled trial of topical LL-37 on venous leg ulcers, ulcers closed no better than with placebo overall.[3]
Regulatory status
KPV and LL-37 left FDA's compounding Category 2 because their nominators withdrew them; FDA's page listing them as withdrawn is dated April 22, 2026 [9]. Neither appears in FDA's 503A category lists updated May 14, 2026, and that is not an approval [14]. Health Canada has warned against injecting peptides bought online [15].
What the scan measures for acne
Since we found no controlled acne trial of any peptide, measurement matters more than any product claim. For acne itself, a dermatologist is the right person to ask.
The SoftMaxx AI skin score looks at acne and scarring, texture and pores from a photo. Scan before a change and every 4 weeks after, in the same light. It is a record of your skin, not a diagnosis.
Side effects and risks
- Animal LL-37: possible flare of rosacea-type redness and bumps, inferred from its role in rosacea (mouse study)[6]
- Human observational LL-37: studies of psoriasis patients link it to immune activation in psoriasis; we found no study of whether applying it can trigger psoriasis[7][4]
- Regulator document KPV: FDA has not identified any human exposure data, so its safety in people is unknown[9]
- Regulator document Injected unauthorized peptides: infections, wrong dose and contaminants (Health Canada)[15]
Regulatory status (checked 2026-09-30)
- United States (FDA)We found no FDA-approved product containing KPV in Drugs@FDA (searched 2026-10-01). (FDA:
Drugs@FDA search: kpv — no approved product found
) FDA removed KPV from 503A Category 2 on 2026-04-22 after the nominations were withdrawn; FDA’s safety page still lists it under “Bulk drug substances nominated but withdrawn”. (FDA:Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act
; FDA:Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks
) We found no FDA-approved product containing LL-37 in Drugs@FDA (searched 2026-10-01). (FDA:Drugs@FDA search: ll-37 — no approved product found
) FDA removed Cathelicidin LL-37 from 503A Category 2 on 2026-04-22 after the nominations were withdrawn; FDA’s safety page still lists it under “Bulk drug substances nominated but withdrawn”. (FDA:Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act
; FDA:Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks
) Afamelanotide is FDA-approved as Scenesse (prescription drug). (FDA:SCENESSE (afamelanotide) implant, for subcutaneous use — Prescribing Information
) - CanadaWe found no product containing KPV in Health Canada’s Drug Product Database (searched 2026-10-01). (Health Canada:
Health Canada Drug Product Database search: kpv — no product found
) We found no product containing LL-37 in Health Canada’s Drug Product Database (searched 2026-10-01). (Health Canada:Health Canada Drug Product Database search: ll-37 — no product found
) - Sport (WADA)KPV is not named on the 2026 WADA Prohibited List; by our reading it falls under S0, non-approved substances. (WADA:
World Anti-Doping Code International Standard Prohibited List 2026
) LL-37 is not named on the 2026 WADA Prohibited List; by our reading it falls under S0, non-approved substances. (WADA:World Anti-Doping Code International Standard Prohibited List 2026
) Afamelanotide is not on the 2026 WADA Prohibited List. (WADA:World Anti-Doping Code International Standard Prohibited List 2026
)
Official sources: FDA: Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks
· FDA: Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act
· FDA document · WADA: World Anti-Doping Code International Standard Prohibited List 2026
Report a side effect
If something went wrong after using any product, tell a clinician and report it. Reports are how regulators find contaminated or mislabeled products.
- FDA MedWatch (United States)
- Canada Vigilance Program (Canada)
Common questions
Does KPV work for acne or rosacea?
We found no human skin trial. The evidence is skin cells in a dish and excised-skin penetration tests, and FDA has not identified any human exposure data for KPV.[1][12][9]
Does LL-37 help with acne?
We found no acne trial. People with rosacea have abnormally high levels of cathelicidin, the protein family LL-37 belongs to, and a mouse study links it to skin inflammation, which is a reason for caution on the face.[6][7]
Is KPV safe?
Unknown. FDA has not identified any human exposure data, and Health Canada lists it among unauthorized injected peptides.[9][15]
Is LL-37 FDA approved?
We found no FDA-approved LL-37 product in Drugs@FDA. It left FDA's compounding Category 2 when its nomination was withdrawn; FDA's page listing it as withdrawn is dated April 22, 2026, and FDA's safety concerns remain posted.[9][14] Source: FDA: Drugs@FDA search: ll-37 — no approved product found
References
Every reference below was matched to its PubMed or DOI record (title checked) before publication. "Verified" means the paper exists and is the one named; what it supports is stated next to each claim.
alpha-Melanocyte-stimulating hormone, MSH 11-13 KPV and adrenocorticotropic hormone signalling in human keratinocyte cells.
PubMed 15102092 DOIPepT1-mediated tripeptide KPV uptake reduces intestinal inflammation.
PubMed 18061177 DOIEvaluation of LL-37 in healing of hard-to-heal venous leg ulcers: A multicentric prospective randomized placebo-controlled clinical trial.
PubMed 34687253 DOIThe antimicrobial peptide LL37 is a T-cell autoantigen in psoriasis.
PubMed 25470744 DOINCT04943159 — Afamelanotide in Patients Suffering With Acne Vulgaris (Phase 2, completed)
SourceIncreased serine protease activity and cathelicidin promotes skin inflammation in rosacea.
PubMed 17676051 DOIPlasmacytoid dendritic cells sense self-DNA coupled with antimicrobial peptide.
PubMed 17873860 DOISCENESSE (afamelanotide) implant, for subcutaneous use — Prescribing Information (Initial U.S. Approval 2019; revised 10/2019)
SourceCertain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks
SourceAntimicrobial effects of alpha-MSH peptides.
PubMed 10670585 DOILysine-Proline-Valine peptide mitigates fine dust-induced keratinocyte apoptosis and inflammation by regulating oxidative stress and modulating the MAPK/NF-κB pathway.
PubMed 40073467 DOITransdermal Iontophoretic Delivery of Lysine-Proline-Valine (KPV) Peptide Across Microporated Human Skin.
PubMed 28343991 DOIThe tripeptide KdPT ameliorates ongoing psoriasis-like skin inflammation in murine and human skin.
PubMed 27376341 DOIBulk Drug Substances Nominated for Use in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act
SourceThink twice before injecting peptides bought online: unauthorized products can seriously harm you (Health Canada advisory; lists KPV)
Source