Compare prices and buy LL-37 from 20 research peptide vendors - also called suppliers or sources. Updated daily.
A 37-amino-acid cationic alpha-helical antimicrobial peptide (CAS 154947-66-7, C205H340N60O53), the C-terminal fragment of hCAP18, the 18 kDa precursor of the only cathelicidin the human genome encodes. Proteinase 3 releases it from hCAP18 in neutrophils, while skin kallikreins and seminal gastricsin cut the same precursor into different peptides. In vitro it permeabilizes bacterial membranes, binds lipopolysaccharide and is chemotactic for neutrophils, monocytes and T cells through the receptor FPR2. Its international nonproprietary name is ropocamptide. Topical formulations have been tested in human chronic-wound trials, and no FDA-approved product contains it.
For research purposes only. Not medical advice.
LL-37 is the 37-residue C-terminal peptide of hCAP18, the 18 kDa human cathelicidin precursor, and the human genome encodes no other cathelicidin (Gudmundsson, European Journal of Biochemistry, 1996). Its sequence, LLGDFFRKSKEKIGKEFKRIVQRIKDFLRNLVPRTES, is residues 134 to 170 of the CAMP gene product (UniProt P49913). FDA's substance registry files it under the international nonproprietary name ropocamptide, with CAS 154947-66-7 as its primary registry number, formula C205H340N60O53 and molecular weight 4493. PubChem also carries a trifluoroacetate salt record, and a milligram of a salt holds less peptide than a milligram of the free peptide.
Processing is tissue-specific. Proteinase 3 cleaves hCAP18 to LL-37 in material exocytosed from neutrophils (Sorensen, Blood, 2001), while skin kallikreins 5 and 7 cut the same precursor into shorter peptides (Yamasaki, FASEB Journal, 2006).
Tumor findings split by tissue, and all of them are preclinical. Neutralizing LL-37 slowed ovarian xenograft growth (Coffelt, PNAS, 2009) and the peptide behaved as a growth factor in lung cancer xenografts (von Haussen, Lung Cancer, 2008), while colon models showed suppression (Ren, Cancer Research, 2012). A 2012 paper calling LL-37 an agonist of the type I insulin-like growth factor receptor was retracted by Oncogene in 2023, so that mechanism has lost its primary support.
Four trials gave the peptide to people, three in wounds. Most registered studies that mention LL-37 gave something else, often vitamin D, and measured cathelicidin.
No FDA-approved product contains LL-37, and drugsfda returns no application under ropocamptide or cathelicidin as of October 2026. FDA placed cathelicidin LL-37 in Category 2 of its Section 503A compounding nominations, the group it says may present significant safety risks, on September 29, 2023. The entry left that table after FDA's April 15, 2026 announcement covering twelve peptides, effective seven days later, because the nominations were withdrawn. Its safety text survived the move to that page's withdrawn-nomination table, where FDA still writes that the peptide may pose an immunogenicity risk by certain routes, that the agency lacks the information to know whether it would cause harm in humans, and that nonclinical findings suggest detrimental effects on male reproduction and protumorigenic effects in some tissues.
LL-37 is one of five substances FDA has named for a Pharmacy Compounding Advisory Committee meeting to be held before the end of February 2027, with GHK-Cu, dihexa, melanotan II and PEG-MGF. As of October 2026 FDA has not set a date, published the Federal Register notice and docket it says it intends to, or named the clinical use it will evaluate for each substance, a column the July 2026 meeting carried. Our February 2027 slate post tracks that record.
They are names for one molecule and its precursor. Cathelicidin is a protein family, and the human genome encodes a single member, from the CAMP gene, whose 18 kDa precursor protein is called hCAP18. LL-37 is the 37-residue C-terminal fragment released from that precursor, and it is the peptide research vendors sell. CAP18 was the name given to a cationic antimicrobial protein purified from rabbit leukocytes, so a listing titled LL-37 (CAP-18) is pointing at the precursor family. Ropocamptide is the international nonproprietary name assigned for drug development. FDA's substance registry files LL-37, cathelicidin LL-37 and ropocamptide under one record, with CAS 154947-66-7 as the primary registry number.
Two trials, with different answers. A first-in-man study published in Wound Repair and Regeneration in 2014 randomized 34 patients with hard-to-heal venous leg ulcers to three concentrations of a topical LL-37 formulation or placebo. Healing was significantly faster than placebo at the lowest concentration only, and no safety concerns were reported. The Phase IIb HEAL LL-37 trial, run by Promore Pharma at 15 sites in Poland and Sweden, then treated 148 patients. In its full analysis set of 144, confirmed complete wound closure was 26.5 percent and 24.7 percent in the two LL-37 arms against 25.3 percent on placebo, and no efficacy endpoint reached statistical significance. A post hoc subgroup of patients with larger wounds improved, which the authors said warrants a trial powered for that group.
Not as of October 2026. FDA's meeting page names cathelicidin LL-37 as one of five bulk drug substances its Pharmacy Compounding Advisory Committee will consider for the Section 503A bulks list, at a meeting the agency says will be held before the end of February 2027. The page states that the time and location will be scheduled in the coming months and that FDA intends to publish a Federal Register notice and establish a public docket for comment. No such notice has appeared in the Federal Register as of October 20, 2026. The page also does not name the clinical use FDA will evaluate for each substance, which the July 2026 meeting materials did. A committee recommendation is advisory, because the bulks list changes through rulemaking.
Because that research treats it as part of the disease mechanism. In psoriasis, LL-37 was identified as the factor that lets plasmacytoid dendritic cells respond to the body's own DNA, by binding that DNA into aggregated complexes that trigger Toll-like receptor 9, reported in Nature in 2007. In rosacea, facial skin was found to carry abnormally high cathelicidin levels and differently processed cathelicidin peptides, and injecting those peptides into mouse skin increased inflammation, reported in Nature Medicine in 2007. Clinical studies in these conditions measure cathelicidin as a marker or test other drugs against it. ClinicalTrials.gov lists no interventional study that administered LL-37 itself for an inflammatory skin disease as of October 2026.
LL-37 is sold by 20 research peptide vendors indexed on PeptideScouter, with 27 tracked listings compared per vendor in the table above. Pricing is normalized and refreshed daily.
18 of the 20 indexed vendors currently have LL-37 in stock. The comparison table marks out-of-stock listings, and stock state is refreshed daily.
Glacier Aminos currently lists LL-37 at $4.69/mg, the lowest listed price across 20 tracked research peptide vendors. With current vendor discount codes applied, the lowest effective price is $3.90/mg.
Discount codes are issued per vendor rather than per peptide, so any code applies across that vendor's whole catalog. All 20 vendors listing LL-37 publish a PeptideScouter code, worth 5% to 50% off. Applied, the lowest effective price falls from $4.69/mg listed to $3.90/mg at Ascension Peptides. Each vendor's code is shown beside its price in the table above.
LL-37 ranges from $4.69/mg to $20.00/mg across 27 listings from 20 research peptide vendors, normalized to USD per milligram and refreshed daily.
20 research peptide vendors currently list LL-37 on PeptideScouter, with 18 in stock right now. We track 27 listings across size and kit variants.
LL-37's CAS Registry Number is 154947-66-7. It is also sold as LL-37 (CAP-18).
