Healing & repair

TB-500

A synthetic fragment of thymosin beta-4, studied in animals for wound healing and cell migration. No approved status and no robust human trials.

Limited evidenceNot approvedAdd to compare

What it is

TB-500 is a synthetic version of the active region of thymosin beta-4, a protein found in most human cells that regulates actin, the structural filament cells use to move. The fragment is not an approved medicine and is sold as a research chemical. It is prohibited in sport.

How it works

1
The parent molecule, thymosin beta-4, binds actin and helps cells change shape and migrate.
2
In animal wound models this is associated with faster movement of repair cells into injured tissue.
3
It has been reported to support blood-vessel formation and to reduce inflammatory signalling in tissue models.
4
Because the fragment is much shorter than the parent protein, how much of that activity it retains is uncertain.

What it's studied for

Skin wound closure (animal and ex-vivo models)

Tendon and muscle repair models

Corneal and cardiac repair models

Hair growth (small cosmetic studies of the parent protein, not the fragment)

Reported and studied effects

Accelerated wound closure in animal models
Increased cell migration in laboratory studies
Reduced scar formation in some models
Human outcome data are essentially absent

Research protocol notes

Research context only

Research context only — no approved human protocol exists. Animal studies used injected doses in the microgram-per-kilogram range over days to weeks. Online cycle recommendations are not derived from controlled human research.

These figures are described so you can understand what researchers did. They are not a dose, a schedule, or a suggestion — and they are not a substitute for a doctor.

Possible side effects and contraindications

Safety profile

Possible side effects

Human safety profile not established
Injection-site reactions reported anecdotally
Headache and lethargy reported anecdotally
Unverified purity is a real risk with unregulated products

Contraindications and cautions

Not established
Pregnancy and breastfeeding should be treated as unknown
Caution with any history of cancer, given proposed effects on cell migration and vessel growth
Prohibited in competitive sport

A side-effect list is never complete, and these are not the only situations that warrant caution. Anything unexpected, or anything you are unsure about, should be discussed with a doctor before use.

Evidence assessment

Limited evidenceSmall human studies or animal data only

Small human studies or animal data only

Animal and laboratory findings exist for the parent protein and the fragment, but controlled human studies are lacking, so claims about human benefit remain unproven.

References

References link to published literature, regulator pages or literature indexes. Where a link points to a search, it collects the peer-reviewed work on that molecule rather than a single study.

Compare TB-500 with another peptide →

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Healing & repair

BPC-157

A synthetic fragment of a gastric protein, widely promoted online for injury recovery. Human trial evidence is very thin; almost all data comes from animal studies.

Limited evidenceNot approved

Healing & repair

KLOW blend (TB-500, BPC-157, KPV, GHK-Cu)

A four-peptide repair and skin stack: animal data on each part, nothing at all on the combination.

Anecdotal evidenceNot approved

Healing & repair

KPV

A three-amino-acid fragment of alpha-MSH promoted for gut and skin inflammation. Anti-inflammatory in cells and animals; there are no human trials at all.

Anecdotal evidenceNot approved