Healing & recovery

TB-500 (thymosin beta-4): benefits, research & what people use it for

Research purposes only Checked against official sources Oct 16, 2026

Quick facts

What it is: TB-500 is a synthetic product based on part of thymosin beta-4, a natural repair-related protein.
Status: research purposes only. Not FDA-approved.
Research: promising early research on thymosin beta-4, the natural repair protein TB-500 is based on.
Dosage: there is no established human dose.
Why it's popular: built on the body's own repair protein, a staple in recovery stacks.

What is TB-500?

Thymosin beta-4 (Tβ4) is a natural protein your body uses for cell movement and tissue repair. "TB-500" is the name for a synthetic product based on part of Tβ4, a favorite in recovery circles. Clinical trials so far have used Tβ4 itself.

Is TB-500 FDA-approved?

Neither TB-500 nor thymosin beta-4 is an FDA-approved drug. The 2026 WADA Prohibited List bans "thymosin-β4 and its derivatives e.g. TB-500" at all times (section S2). FDA's compounding safety page says it identified no human exposure data for the TB-500 fragment (FDA page). Its compounding status is also under review in 2026.

TB-500 dosage: what we actually know

There is no established human dose for TB-500, and FDA says it found no human exposure data for the TB-500 fragment.

Thymosin beta-4 (the parent protein) has been tested in people. One example is a 96-patient heart-attack trial of a recombinant version given after a stent procedure (PMID 41229390). The abstract doesn't state the dose, and the overall result wasn't significant.
Eye-drop versions have been developed for eye-surface conditions (PMID 30063853).

Why the numbers online don't agree

Many online "protocols" are converted from animal studies, where doses are set by body weight in rats or mice. Those don't translate directly to people.
The few human reports use different routes and settings, with no agreed standard.
Unregulated products can vary in what they actually contain.
Sellers and influencers often share numbers without sources.

See Why is peptide info so confusing?

Good questions to bring to a clinician

What is actually in the product, and has it been third-party tested?
Is there any human evidence for my specific goal, or only animal studies?
Could it interact with my other medicines or conditions?
Is there an FDA-approved option for what I'm trying to treat?
How would we know if it's working, or causing harm?

What the research shows

Heart attack trial (Cardiovasc Res, 2025, PMID 41229390): recombinant human Tβ4 was tested in 96 heart-attack patients. The overall difference in infarct size vs. placebo was not significant. A benefit was seen only in a subgroup dosed early.
Eye research review (Expert Opin Biol Ther, 2018, PMID 30063853): describes Tβ4 eye drops being developed for corneal and dry-eye conditions. This is a researcher's narrative review, not trial results.
We found no controlled human trials of products sold as "TB-500."

New to these terms? See the glossary.

TB-500 FAQ

What is the TB-500 dosage?

There's no established human dose because it's research-only.

Is TB-500 the same as thymosin beta-4?

No. TB-500 is a synthetic product based on part of thymosin beta-4. Clinical studies used thymosin beta-4 itself.

Is TB-500 legal for athletes?

No. The 2026 WADA Prohibited List bans thymosin beta-4 and its derivatives, including TB-500, at all times.

Does TB-500 work?

Research on thymosin beta-4, the parent protein, shows repair activity, including a benefit in early-dosed heart-attack patients. Controlled trials of TB-500 itself haven't been published yet.

Research purposes only. Not FDA-approved for human use, and products vary in quality. Findings above are from the studies cited.

Not medical advice. Education only. We don't sell anything or tell you what to take. Label doses are there so you can follow along with your prescriber. Talk to a licensed clinician about your health.

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