Comparison
LL-37 vs. Semax
Two peptides side-by-side — identity, evidence base, legal status and known adverse events.
Identity
Category
Research other
Research other
CAS no.
597562-32-8
80714-61-0
Molecular weight
4493.33 g/mol
813.92 g/mol
Half-life
no data
0.3 h
Sequence
LLGDFFRKSKEKIGKEFKRIVQRIKDFLRNLVPRTESMet-Glu-His-Phe-Pro-Gly-ProMechanism of action
LL-37
LL-37 is a cationic, amphipathic helical peptide and the only member of the cathelicidin family in humans. It is generated by proteolytic cleavage from the C-terminal portion of the precursor protein hCAP18 (CAP-18). Mechanistically it associates with and can permeabilize microbial membranes; in addition it modulates immune cells, influences cytokine release, exerts chemotactic activity, and can bind extracellular self-DNA. Preclinical models have described both anti-inflammatory and pro-inflammatory effects, depending on concentration and tissue context.
Semax
Semax is a tetracosactide fragment analog without hormonal activity at MC2R. Proposed mechanisms include elevation of BDNF and NGF in hippocampus and striatum (in animal models), modulation of dopamine metabolism, and neuroprotective effects via anti-apoptotic pathways. A clear primary receptor is not established.
Evidence base
Highest evidence
Human trial
Human trial
Studies
4
4
of which in humans
1
2
Effects recorded
4
3
Open conflicts
1
1
Documented adverse events
0
1
Legal status
Full entries
Frequently asked questions
- What is the difference between LL-37 and Semax?
- LL-37 is classified as "Research other", while Semax is classified as "Research other". LL-37: LL-37 is the only known human cathelicidin, a 37-amino-acid antimicrobial peptide generated by cleavage of the precursor protein hCAP18. In research it plays a central role in innate immune defence and wound healing, yet acts in a context-dependent manner as both anti- and pro-inflammatory and has been linked to autoimmune processes. LL-37 is not an approved drug; the evidence base is predominantly basic and preclinical. Semax: Synthetic heptapeptide derived from the N-terminal fragment of adrenocorticotropic hormone (ACTH 4-10). Approved in Russia for ischaemic stroke, cognitive function and ADHD in children. Western phase-3 trials absent. This page contrasts both neutrally and source-based — with no usage or dosing recommendation.
- Which peptide is better supported by science, LL-37 or Semax?
- The highest available evidence level is "Human trial" for LL-37 and "Human trial" for Semax. A higher evidence level means more robust data, but says nothing about suitability for an individual. The full body of evidence is on each peptide's own page.
- What is the legal status of LL-37 and Semax in Germany and the United States?
- Germany: LL-37 — Research only, Semax — Unapproved. United States: LL-37 — Research only, Semax — Unapproved. These are factual summaries with source and review date on the individual pages.