Thymosin Alpha-1 vs LL-37
Key differences, research and prices — side by side.
The key difference
Both are immune-related. Thymosin alpha-1 modulates immune-cell activity and is approved abroad as thymalfasin. LL-37 is the body’s own antimicrobial peptide, studied for directly attacking bacteria and biofilms and for wound healing.
| Thymosin Alpha-1 | LL-37 | |
|---|---|---|
| What it is | Thymosin alpha-1 is a 28-amino-acid peptide originally isolated from the thymus, the organ where immune T-cells mature. | LL-37 is the only cathelicidin antimicrobial peptide made by the human body, named for its 37 amino acids beginning with two leucines. |
| How it works | It acts on immune cells through toll-like receptors and has been shown to influence T-cell maturation and the body’s response to infection. | It can disrupt bacterial membranes and also signals to immune cells, playing a role in the skin’s and gut’s first-line defenses. |
| Research areas |
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| Evidence | Human clinical studies | Mostly animal & lab studies |
| Regulatory status | Approved as a drug (thymalfasin, Zadaxin) in several countries outside the U.S. Not approved by the FDA. | Not approved by the FDA as a drug. |
| Research area | Immune | Immune |
| Sequence | — | — |
| Lowest price | $5.22/mg → | $6.80/mg → |
| Tested vendors | 2 | 2 |
| Third-party lab results | 3 COAs | 1 COAs |
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Educational comparison of published research — not medical advice, and not a recommendation of either compound. Prices are for reference only. Compounds referenced are sold by third parties for laboratory research use only and are not for human consumption.