Muscle & Recovery · Coming soon

TB-500, prescribed — not just shipped.

A synthetic fragment of thymosin beta-4, studied for cell-migration signaling and the tissue-repair processes involved in recovery.

Coming soon

You are on the list. We will email you when TB-500 becomes available — and nothing else. Joining is not a medical request, and no prescription has been issued.

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TB-500 is coming soon to Promise. Add your email and we'll let you know when visits open.

We store your address and which treatment you asked about, and use it only to tell you if TB-500 becomes available. Joining is not a medical request and no prescription is issued from this form.

A licensed provider reviews every request; not everyone qualifies.

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Call (602) 737-2202

Closed · opens today 10 a.m. AZ

A licensed clinician in a consultation room
TB-500 vial and spec card
TB-500 · Coming soon

How it works once TB-500 is available

  1. 1

    Share your health history

    Every treatment gets its own online clinical questionnaire — your history, medications, and goals.

  2. 2

    A licensed provider reads it

    A real person goes through your history and takes the time to get it right before anything is decided.

  3. 3

    They prescribe — or they don't

    If a treatment isn't right for your history, you'll hear that plainly. That review is the whole point.

  4. 4

    Your pharmacy compounds it

    Made for your prescription by a licensed U.S. pharmacy and shipped in temperature-safe packaging.

  5. 5

    You choose whether to continue

    Your care team checks in after it arrives. Adjust with your provider, or cancel at any time.

How TB-500 will be offered

TB-500 will be offered as an injectable. Your provider decides whether it's appropriate — including whether a different treatment would serve you better.

  • Injectable

    10 mg / 3 mL vial

The safe way to take TB-500 seriously

TB-500 is easy to find online and hard to trust there. Promise works the way medicine is supposed to work — a clinician decides, a licensed pharmacy fills, and someone stays accountable to you.

A real prescription

Prescribed for you specifically, after a real look at your health history — never pulled off a shelf.

A real pharmacy

Your prescription is compounded for you by a licensed U.S. pharmacy — not a mystery vial from an unregulated website.

Real oversight

Temperature-safe shipping, follow-up check-ins, and a care team that answers — before and after your medication arrives.

Product details
Available as
Injectable
Supply
10 mg / 3 mL vial
Pharmacy
Compounded by a licensed U.S. pharmacy
Availability
Coming soon — add me to the list to be notified

Studied for cell migration

Thymosin beta-4 binds actin, the protein cells use to move. That regulation is the mechanism most of the TB-500 research examines.

A fragment, not the whole protein

TB-500 is built from the active region of a protein present in nearly every human cell, which is why it is studied in tissue-repair models.

Prescribed, never simply supplied

A licensed provider reads your history, decides whether TB-500 fits it, and sets the protocol.

In brief.

TB-500 is a synthetic fragment of thymosin beta-4, a protein your cells already make, and it is studied for one of the least glamorous and most necessary parts of healing: getting repair cells to the place that needs them. Interest in it has grown faster than the clinical evidence, which is why Promise will offer it one way only: a licensed provider reviews your health history and prescribes it only when treatment is appropriate for you. TB-500 is coming soon to Promise — add me to the list.

What TB-500 is

Thymosin beta-4 is present in nearly every human cell and is involved in how cells move and how tissue reorganizes itself after damage. TB-500 is a short synthetic peptide based on the active region of that protein — the working end, without the rest of the molecule. It sits in our muscle and recovery category and appears in both of our recovery blends, Wolverine and KLOW.

It is also the peptide most often studied next to BPC-157, and the two get discussed almost interchangeably in places they should not be. They are not the same tool. Research on both is largely preclinical; human studies of the parent thymosin beta-4 do not establish evidence for the TB-500 fragment, for which FDA identified no clinical studies in humans.

How it is studied to work

The mechanism research keeps returning to actin. Actin is the structural protein cells use to change shape and crawl, and thymosin beta-4 binds it — regulating the pool of actin a cell can draw on when it needs to move. Studies read TB-500 as acting on that same regulation, which is why cell migration toward a site of injury is the central question in the literature.

Downstream of that, researchers have looked at the formation of new blood vessels and at how tissue organizes itself as it rebuilds, both of which depend on cells arriving where they are needed. Range of motion and post-exertion recovery come up frequently in discussion of the compound. Those are studied questions about a mechanism, not statements about what any individual will experience.

How TB-500 is prescribed

TB-500 will have its own intake questionnaire — a different clinical form from every other product we offer, because it is a different clinical decision. Once visits open, you complete it, and a licensed provider reviews your health history, current medications, and what you are trying to address.

They prescribe only when TB-500 is appropriate for you. Not everyone qualifies; requests are declined on medical grounds. If a different approach fits your history better — BPC-157 on its own, a combined protocol, or nothing at all — that is the provider's call to make with you.

What treatment looks like

If you are prescribed, your medication is compounded and dispensed by a licensed U.S. pharmacy, and shipped in discreet, temperature-safe packaging. Your provider sets the protocol from your evaluation; there is no dose to look up, because the right one is a clinical decision about you.

After that, your care team checks in. Adjustments happen with a clinician in the loop, not on your own read of how the week went. TB-500 is designed to sit alongside the fundamentals — sleep, nutrition, and training you can actually recover from — rather than substitute for any of them.

Common questions

What is TB-500?

TB-500 is a synthetic peptide based on the active region of thymosin beta-4, a protein present in nearly every human cell and involved in cell movement and tissue organization. It is studied for cell-migration signaling — specifically its interaction with actin, the structural protein cells use to travel toward damaged tissue — and for the repair processes that depend on it. Human studies of the parent thymosin beta-4 should not be treated as studies of the TB-500 fragment; FDA identified no clinical studies of the fragment administered to humans.

Is this real TB-500, or a research chemical?

A real prescription. TB-500 is coming soon to Promise, and when visits open, a licensed provider will review your history before deciding whether to prescribe it; if it is prescribed, a licensed U.S. pharmacy will compound the medication for you. It will not be a product labeled for laboratory use.

Does starting a visit guarantee a prescription?

No. A licensed provider reviews every TB-500 request and prescribes only when it is appropriate for you. If it isn't, you'll be told plainly — that review is the point.

Do I need a prescription for TB-500?

Yes. TB-500 is prescription-only, and it is coming soon to Promise. Once visits open, you complete the intake questionnaire for it, a licensed provider reviews your health history, and they prescribe only when treatment is appropriate for you.

Is TB-500 FDA-approved?

No. TB-500 is not FDA-approved. It is coming soon to Promise as a compounded medication, and compounded medications are not reviewed by the FDA for safety, effectiveness, or quality. When visits open, it will be prepared by a licensed U.S. compounding pharmacy against a prescription written for you specifically, after a licensed provider has reviewed your health history.

How does the online visit work?

TB-500 is coming soon to Promise — you can add your email on this page to hear when visits open. Once visits open, you start with the intake form for TB-500, which is its own clinical questionnaire — every product has a different one. A licensed provider reviews your answers and prescribes only if TB-500 is appropriate for you. If it is, your medication is compounded and dispensed by a licensed U.S. pharmacy and shipped in temperature-safe packaging, with follow-up check-ins from your care team.

How is TB-500 different from BPC-157?

The two are studied at different points in the repair process. TB-500 is a fragment of thymosin beta-4, and its research centers on actin regulation and cell migration — how repair cells reach the tissue that needs them. BPC-157 is a 15-amino-acid sequence modeled on a protein found in gastric juice, and it is studied for blood-vessel formation signaling and for the gut lining. They are often studied as a pair, which is what our Wolverine protocol combines. Promise offers Wolverine and BPC-157 by prescription, and TB-500 on its own is coming soon; a licensed provider decides which option fits your history, if any does.

How is this different from TB-500 sold online?

TB-500 sold online without a prescription is usually labeled for laboratory use, with no provider, no pharmacy, and no one accountable if something goes wrong. Promise works the way medicine is supposed to: a licensed provider decides, a licensed U.S. pharmacy compounds your prescription, and a care team follows up.

Related treatments

Other Muscle & Recovery options a provider may consider.

Recovery KLOW vial and spec card

KLOW

Muscle & Recovery

Four-peptide blend — BPC-157, GHK-Cu, KPV, TB-500 — studied for tissue repair, skin, and recovery support.

About KLOW →

From $249Start visit

Requires an online medical evaluation. Prescribed only when a licensed provider determines it's appropriate.

Recovery Wolverine blend vial and spec card

Wolverine

Muscle & Recovery

BPC-157 + TB-500 — the classic two-peptide recovery pairing, prescribed as one blend.

About Wolverine →

From $199Start visit

Requires an online medical evaluation. Prescribed only when a licensed provider determines it's appropriate.

Recovery BPC-157 vial and spec card

BPC-157

Gut Health & Digestion

A 15-amino-acid synthetic peptide studied for tissue-repair signaling, gut-lining support, and recovery.

About BPC-157 →

From $229Start visit

Requires an online medical evaluation. Prescribed only when a licensed provider determines it's appropriate.

Explore Muscle & Recovery →

Read more about TB-500

The latest from the Promise team on TB-500.

  1. The bottom steps of a wooden staircase with a pear

    TB-500 Myths: Ten Claims Checked Against Studies

    TB-500's benefits in humans have not been established. Ten common claims get graded against the actual molecule, study and outcome behind them.

    October 10, 2026 · Julian Reyes, Health Writer
  2. One plain ceramic mug on bare wood, a close view

    TB-500 News Update: October 2026

    A new rat study adds tendon data, while the human evidence gap remains. July's FDA review and September's sports list answer different questions.

    October 2, 2026 · Priya Raman, Health Writer
  3. A woman sits on the edge of a raised garden bed holding a lemon

    Peptide Myths: 10 Common Claims Checked

    Ten things people say about peptides online, from "they're steroids" to "drug tests can't find them," graded against the studies and the rules that can actually answer them.

    September 30, 2026 · Elena Marsh, Health Writer
All 33 articles on TB-500 →