TB-500 20mg Pen

This listing is a sealed ProPeptide pen that carries TB-500 already dissolved. The manufacturer's label states 20mg of peptide in 3mL and names the contents as Ac-LKKTETQ: seven amino acids, acetylated at the start, matching positions 17 to 23 of thymosin beta-4 (Tβ4).

That is the definition FDA and the anti-doping literature use, and it is worth holding onto. Native Tβ4 is a far larger molecule, 43 amino acids and about 4,963 g/mol, while the fragment weighs roughly 889 g/mol. The fragment keeps the stretch of Tβ4 that binds actin, but it lacks the N-terminal AcSDKP sequence (positions 1 to 4), so findings tied to AcSDKP do not carry over to it.

Material sold as TB-500 is not uniform across the market. Anti-doping laboratories have found products that contain, or claim, the full-length protein instead. The practical check is mass: a certificate reporting about 889 g/mol points to the fragment, and one near 4,963 g/mol points to full-length Tβ4.

For the mechanism and evidence in depth, see our TB-500 research review.

Remy Research lists TB-500 in two formats.

Solution instead of powder

The peptide comes already dissolved, so there is no lyophilised cake to handle and no preparation step before the material reaches an assay. The trade-off is stability: peptides in solution are generally less tolerant of warmth and time than freeze-dried powder, which makes unbroken refrigeration more important for this format. Labs that prefer powder can order the TB-500 10mg vial instead.

A larger single unit

At a 20mg label claim, one pen holds twice the stated peptide content of the 10mg vial in a single sealed device, with one lot number and one expiry date to record.

Batch evidence: pending

The line is specified at ≥99% purity. No independent batch report exists for this pen so far; once one is released it will be listed in our lab results library. Until then, the mass and purity figures are manufacturer claims rather than third-party measurements. For what a full certificate ought to include, see our COA and HPLC guide.

Refrigerated from shelf to door

Each parcel is packed to stay between 2 and 8°C in transit. Within Dubai, orders placed before 4 PM arrive that day, usually inside 4 hours, while the other emirates get next-day delivery on orders in by noon. See the delivery page for charges and terms.

Much of what is written about TB-500 actually describes experiments on full-length Tβ4, which changes how strongly any finding applies to this pen.

What belongs to full-length Tβ4

Tβ4 is the main protein that holds monomeric G-actin in mammalian cells, binding it one-to-one. Cell and rodent studies link the full protein to cell migration, new vessel growth and repair in cardiac, corneal and skin injury models; a 2004 mouse study after experimental myocardial infarction is among the most cited. Those results come from the 43-residue protein, not from the fragment.

What is known about the fragment

Far less. Activity has been reported for the unacetylated peptide LKKTETQ, but a 2024 analysis concluded that the biological effects of TB-500 itself have not been documented. In that study's fibroblast assay, a breakdown product, Ac-LKKTE, showed significant wound-healing activity while the parent fragment did not.

Where the human data stops

Every human study so far involved full-length Tβ4, chiefly the RGN-259 eye-drop programme for dry eye, whose Phase 3 results were mixed and which remained unapproved by FDA as of April 2026. No registered human trial has tested the TB-500 fragment, and no human pharmacokinetic profile for it has been published.

Set against BPC-157

TB-500 sits in the actin and cell-migration lane, BPC-157 in vascular and nitric-oxide signalling. Our BPC-157 vs TB-500 comparison lays the two side by side, and the BPC-157 + TB-500 blend vial holds both in a fixed ratio.