Thymosin alpha-1 with KPV and LL-37 dosage and evidence
Written by Aaron CuhaReviewed Sep 2026
The short answer
A three-peptide immune blend from the clinic end of the market.
Evidence grade for Thymosin alpha-1 with KPV and LL-37: Strong. The rule: at least two finished studies in people, and at least 1,000 people who took it. The sum on this page: 3 completed trials, 1,140 people given it. A grade counts how much has been done to people, not whether it works.
- People given it
- 1,140
- Human studies
- 3
- Found nothing
- 1
Dose
No human dose established
Amounts that were given in studies sit in Human evidence on this page. None of them is a personal dose.
3 completed trials, 1,140 people given it
6 effects reported, 4 unwanted, 2 wanted, by people using it, not a trial
Goal pages: Fat loss and metabolism, Ageing and longevity, Injury, healing and recovery, Skin, hair and appearance
In plain English
In plain English, from Aaron
This is how I would explain it to a friend. The evidence, with the numbers, is further down the page.
A three peptide immune blend from the clinic side of this market. One organises the immune system, one calms inflammation, one kills bugs. The one with the biggest trial behind it was tested in 1,106 people and it did not work.
What people take it for
- Getting fewer colds and infections.
- Long term infections that will not clear.
- Gut inflammation.
- Immune support after being ill.
What studies in people showed
Nobody has tested the three together. Thymosin alpha-1 got a proper test. A trial put 1,106 adults with sepsis into two groups across 22 hospitals, and nobody knew who got what. Deaths at 28 days were 23.4 percent on the drug and 24.1 percent on the dummy. No real difference. Nothing else differed either. Several of the doctors running it got grants from the maker, which the paper says. LL-37 has the best file of the three, and it is for wounds you put it on. Thirty four people with stubborn leg ulcers got it as a topical treatment. The two lower strengths healed about six times and three times faster than the dummy, and ulcer size dropped 68 percent and 50 percent. The strongest one did nothing at all. Read that again, because it matters: more was not better. A later trial tested an LL-37 cream on diabetic foot ulcers. KPV has no human data of any kind. Sellers do not agree on vial sizes, so no per unit number here.
What people report
Reports, not study results
The good
- Fewer or shorter colds over a winter.
- Gut symptoms settling, credited to the KPV.
The bad
- Flu like symptoms and tiredness in the first days.
- Shot site reactions and hot itchy flushing, reported more for the LL-37 part.
- Nothing at all.
- One part calms inflammation, one part stirs the immune system up, and one part can do either. Nobody has checked whether they add up or cancel out.
Where these come from: Clinic write-ups and forums for long term infection. People talking, about something that changes with the seasons and that almost nobody counted before they started.
My bottom line
The wound trial here teaches the thing blends get wrong. The strongest dose worked no better than nothing. More of a good ingredient is not automatically better, and nobody picked these amounts from data.
An opinion, not a finding. I am a coach, not a doctor.
What it has been measured to do
Measured in people
Goals Thymosin alpha-1 with KPV and LL-37 has been tested for in people, biggest studies first. We count only what the studies on this page say, so the real numbers may be higher.
- Living longer1,106 people · 1 study
- Wound and skin healing34 people · 2 studies · 1 found nothing
What people using it report
Real people telling you what happened to them. Nobody checked it, and the people who post are not a fair sample, so it cannot prove anything works. It is still the best guide on this page to what people actually do with Thymosin alpha-1 with KPV and LL-37, what they expect, and what goes wrong. The full account, including the negative reports, is below.
Animal and lab work, not yet tested in people
Real results, but from animals or cells, not people. What works in a mouse often does not work the same way in a person. Nobody can patent this, so nobody would ever earn back the cost of a study in people. That is usually why there is none. The record on this one is set out below.
- Losing weight1 animal or lab study
31 of the 36 indexed goals have no study of any kind behind Thymosin alpha-1 with KPV and LL-37
No study in people, animals or cells on this page reports a result for these. That does not prove Thymosin alpha-1 with KPV and LL-37 does nothing for them. It does mean anything you have heard about Thymosin alpha-1 with KPV and LL-37 and one of these did not come from a study cited here.
Show full evidence
What is Thymosin alpha-1 with KPV and LL-37?
A three-peptide immune blend from the clinic end of the market. The ingredient with the biggest study, thymosin alpha-1, was tested in 1,106 adults with sepsis, a life-threatening blood infection. It did not lower deaths at 28 days: people on the dummy shot did just as well. LL-37 has two small studies as a wound cream, both with good results. KPV has no data in people. Nobody has tested the mix, and no vial size is standard.
The pitch is that one peptide organises the immune system, one calms swelling, and one kills germs while helping tissue heal. Each third has its own evidence. And one of those records has a large study that found no benefit, which rarely shows up in the sales copy.
Thymosin alpha-1 is a peptide from the thymus, 28 building blocks long. It is an approved medicine in several countries. The TESTS study put 1,106 adults with sepsis, at 22 hospitals in China, by chance on thymosin alpha-1 shots under the skin or dummy shots, every 12 hours for seven days. After 28 days, 23.4% of the treated group had died, against 24.1% of the dummy group. That is no real difference. Nothing else the study measured, including safety, came out different either. The study found no clear evidence that thymosin alpha-1 lowers deaths from sepsis. Groups picked out before the study hinted at different effects by age and by diabetes. Several researchers got grants from the drug's maker, and the paper says so.
That was a large, careful, final-stage study against a dummy, where neither patients nor staff knew who got what. It tested the ingredient in this blend with the most evidence, and it found no benefit in the people it studied. That does not mean the peptide does nothing anywhere. It is still the most useful single result about it.
LL-37 is the body's own germ-killing peptide. Its evidence is as a cream on wounds. In the first study in people, 34 people with stubborn leg ulcers from poor vein flow were put by chance on LL-37 cream or a dummy cream. At 0.5 and 1.6 mg/mL, wounds healed about six times and three times faster than on the dummy. Ulcer size fell by 68% and 50% on average in those groups. The strongest dose, 3.2 mg/mL, did no better than the dummy. A later study tested LL-37 cream on foot ulcers in people with diabetes, with patients and staff not knowing who got what. Both studies put it on wounds.
KPV has no data in people at all, by any route, and no listed study.
No seller or pharmacy split is standard for this trio. So this page does not give per-unit amounts. What we can say is this. The ingredient with a large study that found no benefit, and the ingredient with no data, are sold next to the one with small good results as a cream. And the product is injected, not put on a wound.
How does Thymosin alpha-1 with KPV and LL-37 work?
Thymosin alpha-1 tunes the immune system's T cells and the signals they use, such as interleukin-2 and interferon gamma. LL-37 is a germ-killing peptide. It kills germs directly and also tunes the immune system. In some settings it can also stir up swelling. KPV is a tiny tail cut from a skin hormone, and it turns down swelling signals. No paper says what the three do together. One can stir up swelling in some settings, and another calms it. Nobody has worked out how those effects play against each other.
What have studies in people found about Thymosin alpha-1 with KPV and LL-37?
One ingredient has a large final-stage study that found no benefit. One has two small wound cream studies with good results. One has no data in people.
- Thymosin alpha-1 in sepsis: 1,106 adults. At 28 days, 23.4% had died on the drug, against 24.1% on the dummy. No clear evidence of benefit.
- LL-37 in leg ulcers from poor vein flow: 34 people. At the two lower strengths, wounds healed about six and three times faster than on the dummy, and ulcer size fell 68% and 50%. The strongest dose did nothing.
- LL-37 in diabetic foot ulcers: a proper study of the cream, with patients and staff not knowing who got what.
- KPV: no data in people of any kind, and no listed study.
- The blend: no published study and no listed trial.
What this does not tell you: The LL-37 evidence is a cream on open wounds, at set strengths. Injecting it for whole-body immune effects is a different thing, and nobody has studied it. And depending on the setting, the peptide can stir up swelling as well as kill germs.
What do people who took Thymosin alpha-1 with KPV and LL-37 report?
This is what real people say happened to them, good and bad. Nobody measured it. A report cannot tell a real effect from the lift people get just from expecting it to work, from a diet or training change made at the same time, or from what was really in the vial. We still put it near the top. It is the next best thing to a study in people: what happens when real people use it, including what goes wrong.
- Fewer or shorter chest and throat infections over a season. This is the main claimed effect.
- Gut problems calming down, which people credit to the KPV.
- Flu-like symptoms or tiredness in the first days, which people describe as an immune response.
- Reactions where the shot goes in, and allergy-type flushing. People report this more for the LL-37 than for the others.
- Nothing at all.
Sources: Clinic write-ups, chronic infection and peptide forums. Uncontrolled self-reports in a domain where seasonal variation dominates and where infection frequency is rarely counted before starting.
The state of the research
The LL-37 dose result is the most useful thing on this page, and it is worth reading slowly. The two lower strengths worked. The strongest strength did no better than the dummy. That is the opposite of the idea behind most blend dosing, which is that more of a good ingredient is better. Where someone actually measured doses in this family, more was not better.
The second point is about the sepsis study. A failed final-stage study in very sick patients does not settle whether a peptide helps the immune system of a healthy person who keeps getting infections. But it does mean the ingredient here with the biggest and best-run study in people did not improve what it was tested for. That fact belongs next to any claim made for it.
Third, how they act together. One ingredient calms swelling. One boosts the immune system. One kills germs and, in some settings, stirs up swelling. Mixing them at a fixed ratio assumes those effects add up. Nobody has checked whether they cancel out.
The evidence, in charts
Fig. 1a · how many people
1,140people, across 2 studies in people cited here
| Study | People | Share |
|---|---|---|
| TESTS, BMJ 2025 | 1,106 | 97% |
| Wound Repair and Regeneration 2014 | 34 | 3% |
One study holds 97% of these people, so the total rests more on one study than its size suggests. Counts are the number of people each study on this page says it signed up. That includes studies that only watched people and gave nobody the compound. 1 more study in people gives no headcount and is not counted here. Studies still signing people up are left out, and only studies cited on this page are counted.
Fig. 1b · evidence mix
3 of 5 sources here are studies in people. The rest are not.
- Study in people · done in people360%
- Animal study · done in animals120%
- Review of studies · sums up other studies120%
Counted from the list of sources on this page. It counts only what we cite, so there may be more studies out there. A review counts once, however many studies it sums up.
Fig. 2 · evidence over time
The studies cover 5 different years, 2008 to 2025, counted from the list of sources on this page.
Fig. 3 · legal status at a glance
US
Not approved
UK
Not approved
AU
Not approved
CA
Not approved
Not approved in any of the four countries shown. This is what the law says, not a verdict on the science. See Legal status below for the full text and any notes.
Fig. 4 · how much does what
Nobody has tested different amounts in people
This chart would show how the effect changes as the amount goes up. For this compound, nobody has measured that in people. So we leave it empty. We will not borrow an animal chart and pretend it works the same in people.
Fig. 5 · what the molecule is
- Kind of compound
- Blend
- Molecule weight
- Not on file
- Half-life
- Stated in words, not a numbersee the exact wording below
- Chain length
- None on file
Half-life as stated on file: Not defined for the blend. No pharmacokinetic study of the mixture exists and the components differ in clearance.
No amino acid sequence is on file for Thymosin alpha-1 with KPV and LL-37, which is expected: a blend is not built from amino acids.
Fig. 6 · what is in the vial
We cannot show how much of each is in this blend
Sellers do not agree on a vial size for Thymosin alpha-1 with KPV and LL-37, so nobody outside can know how much of each ingredient is in it. Splitting the bar evenly would make up the very number this page is here to question.
- Thymosin alpha-1Strong. At least two finished studies in people, and at least 1,000 people who took it. 2 completed trials, 1,204 people given it.amount not stated
- KPVAnimal or lab only. Only animal or lab studies on this page. No study in people yet. 2 animal studies, no human study.amount not stated
- LL-37Moderate. At least one finished study in people, and at least 100 people who took it. 2 completed trials, 182 people given it.amount not stated
Ingredient list from the product labels we have. Amounts are what the label says is in the vial, never a dose.
The studies we cite
- Study in people2025The efficacy and safety of thymosin α1 for sepsis (TESTS): multicentre, double blinded, randomised, placebo controlled, phase 3 trial
This was the biggest test thymosin alpha-1 has been through, and it failed. Just over a thousand people seriously ill with sepsis got either the peptide or a dummy shot for a week. Nobody involved knew which. A month later, the same share had died in each group. Nothing else measured came out different. A study this size would have found a benefit if there was one. Some authors were paid by the maker, and they said so.
1,106 adults with sepsis across 22 centres in China, randomised 1 to 1 to subcutaneous thymosin alpha-1 or placebo every 12 hours for seven days. 28 day all cause mortality was 23.4% on thymosin alpha-1 and 24.1% on placebo, hazard ratio 0.99, 95% CI 0.77 to 1.27, p = 0.93. No secondary or safety outcome differed significantly. The trial found no clear evidence that thymosin alpha-1 decreases 28 day mortality in sepsis. Several authors received grants from the manufacturer, disclosed in the paper.
- Study in people2014Treatment with LL-37 is safe and effective in enhancing healing of hard-to-heal venous leg ulcers: a randomized, placebo-controlled clinical trial
A cream made from LL-37 healed stubborn leg ulcers faster, in a small first test in people. 34 people first used a dummy cream for three weeks. Then they got LL-37 at one of three strengths, or a dummy, for four more weeks, and nobody knew which. The two lower strengths healed wounds about six and three times faster than the dummy. Ulcer size fell 68% and 50%. The strongest dose did no better than the dummy. This was a cream on a wound, not a shot.
34 participants with venous leg ulcers, three week open-label placebo run-in then four weeks of randomised double-blind twice weekly topical LL-37 at 0.5, 1.6 or 3.2 mg/mL or placebo. Healing rate constants at 0.5 and 1.6 mg/mL were about six-fold and three-fold higher than placebo, p = 0.003 and p = 0.088. Mean ulcer area fell 68% and 50% in those groups. The highest dose showed no difference from placebo. Topical, on wounds, first in man.
- Study in people2023Efficacy of LL-37 cream in enhancing healing of diabetic foot ulcer: a randomized double-blind controlled trial
LL-37 was tested again, this time as a cream on foot ulcers in people with diabetes. People got it or a comparison by chance, and nobody knew who got what. This is only the second proper study of the peptide in people. Note the form both times. A cream, on a wound. Neither study injected LL-37. Neither tested it for the whole-body immune effects it is sold for.
A randomised double-blind controlled trial of LL-37 cream in diabetic foot ulcer healing. The second controlled human study of this peptide and again topical, on a wound, rather than injected for systemic immune effect.
- Review of studies2019Are melanocortin peptides future therapeutics for cutaneous wound healing?
This is a skin doctors' review, not a test. It says KPV is a small piece of a skin hormone that keeps the calming effect but does not tan the skin. It suggests peptides like this could one day help wounds heal. The work it covers is computer models, cells in a dish, skin samples and animals. None of it is in people.
A dermatology review describing KPV as a truncated alpha-MSH peptide that keeps the anti-inflammatory activity without the pigment-inducing activity, and proposing peptides of this class as future candidates for cutaneous wounds. The experimental approaches it surveys are in silico, in vitro, ex vivo and animal.
- Animal study2008Melanocortin-derived tripeptide KPV has anti-inflammatory potential in murine models of inflammatory bowel disease
In mice with an inflamed colon, KPV helped. The mice got better sooner and gained back more weight. Their colon tissue showed less swelling. This was two kinds of mouse gut disease, with KPV given on its own. It says nothing about people or about a blend.
In two mouse colitis models KPV produced earlier recovery, greater body-weight regain, fewer inflammatory infiltrates and lower myeloperoxidase activity in colon tissue. Mice, KPV given alone, nothing here about a blend or about people.
Where to buy Thymosin alpha-1 with KPV and LL-37
No seller we track lists Thymosin alpha-1 with KPV and LL-37 yet. We read sellers’ public product lists every week, and this section fills in as soon as one does. Every seller, graded
Common questions
Has Thymosin alpha-1 with KPV and LL-37 been tested in people?
Yes. 1,140 people given it across 3 completed trials cited here, 1 of which found nothing. A three-peptide immune blend from the clinic end of the market.
What is the Thymosin alpha-1 with KPV and LL-37 dosage?
No human dose established. Amounts that were given in studies sit in Human evidence on this page. None of them is a personal dose. 3 completed trials, 1,140 people given it
Is Thymosin alpha-1 with KPV and LL-37 FDA-approved?
Thymosin alpha-1 is approved in several countries outside the United States, but not by the FDA. LL-37 and KPV are not approved anywhere. The combination has never been reviewed.
Did the thymosin alpha-1 trial work?
No. In 1,106 adults with sepsis, 23.4% had died at 28 days on thymosin alpha-1, against 24.1% on the dummy shot. The study found no clear evidence of benefit.
What is the LL-37 evidence?
Two proper studies, both using a cream on wounds. In leg ulcers from poor vein flow, the two lower strengths made wounds heal about six and three times faster than the dummy. The strongest strength did nothing. A later study tested the cream on foot ulcers in people with diabetes.
Does KPV have human data?
None, by any route, and no listed study. The record is mice with gut disease, cells in a dish, and review articles.
Is more of each better?
The one dose test in this family says no. In the leg ulcer study, the strongest LL-37 cream did no better than the dummy, while the two weaker ones worked.
What vial size should I expect?
There is no standard split for this trio, which is why this page does not give per-unit amounts. Work them out from the milligrams on your own label.