BPC-157 + TB-500 FRAG Blend

The BPC-157 + TB-500 FRAG Blend is the fragment version of the well-known BPC + TB Blend. Instead of full-length TB-500, the vial holds TB-500 FRAG, the short piece of thymosin beta-4 that carries the actin-binding site (amino acids 17 to 23, sequence LKKTETQ). Alongside it sits BPC-157, the pentadecapeptide from gastric juice and one of the most studied peptides in regeneration research. Both single compounds have their own lexicon entries.

The 20 mg vial contains 10 mg of BPC-157 and 10 mg of TB-500 FRAG as freeze-dried powder that you dissolve with bacteriostatic water. The ratio is fixed, you dose the total amount. Compared with the blend built on full TB-500, the fragment is far smaller (seven instead of 43 amino acids). The perceived advantage is a more compact action focused on cell migration and new vessel formation.

For context: there are no human studies on the mix itself. Both components are essentially supported by preclinical work. Neither is approved as a medicine anywhere.

This information is for research and educational purposes only. No medical advice.

In mammalian cells thymosin beta-4 is the main peptide that binds and holds free actin. Through that it influences how mobile cells are. Studies suggest that the actin-binding site in particular is essential for its angiogenic effect: in assays with endothelial cells and vessel sprouts, the seven-residue motif LKKTETQ acted almost as strongly as the whole protein at around 50 nM, while peptides lacking the motif were inactive (Philp 2003). In aged mice the synthetic fragment promoted wound repair comparably to full thymosin beta-4 (Philp 2003, Wound Repair and Regeneration).

Just as important is what the fragment lacks. Thymosin beta-4 has several active sites: the N-terminal Ac-SDKP dampens inflammation and fibrosis, a longer N-terminal stretch supports cell survival and the stretch around LKKTETQ accounts for cell migration, wound healing and angiogenesis (Sosne 2010). TB-500 FRAG therefore covers the migration and vessel part, not the complete anti-inflammatory profile of the full molecule. If that is what you are after, the BPC + TB Blend with full TB-500 is the closer match.

BPC-157 works at a different point. In animal models it promotes the formation of new blood vessels and acts through the nitric oxide system on blood flow and tissue protection. In rat tendon fibroblasts it accelerated outgrowth from tendon tissue, improved survival under oxidative stress and increased migration, likely via the FAK-paxillin pathway (Chang 2011). The idea behind the blend is that BPC-157 acts more on the structural repair of connective tissue and gut lining, the fragment more on cell movement and vascular supply.

• The 20 mg blend vial (lyophilized powder, both compounds together).
• Bacteriostatic water, 2 ml is enough for one vial.
• U-100 insulin syringes with a fine needle (29 to 31 G) and alcohol swabs.
• A spot in the fridge for the reconstituted vial.

Use the calculator above, all values refer to the total amount in the vial. With 2 ml of bacteriostatic water the 20 mg vial gives 10 mg per ml. A shot of 0.5 mg total (0.25 mg BPC-157 + 0.25 mg FRAG) is then 5 units on the U-100 syringe, 1 mg total is 10 units.

With 3 ml you get 6.67 mg per ml and 7.5 units for 0.5 mg, which falls halfway between two marks. With 1 ml it would be 2.5 units, again a half mark and a very small volume on top. With 2 ml both steps land on whole units (5 and 10), which makes 2 ml the practical choice.

Simply add the water to the vial, it can go in briskly and straight onto the powder. Then swirl or shake until everything has dissolved, both are fine. The solution is clear to slightly hazy. Both are usable. If it turns gel-like or forms clumps, the vial is no longer okay.

Subcutaneous into the fat under the skin. Many inject close to the affected region because that is how BPC-157 is described. Whether the site matters for the fragment has not been studied. This is experience, not study evidence.

Disinfect the site with an alcohol swab, pinch a skin fold, place the needle briskly and inject slowly. With daily shots rotate the sites so the skin does not get irritated. Small redness or a bump that is gone after a day is normal.

Use a fresh syringe for every shot, never return anything from the syringe into the vial and put the vial back in the fridge between shots.

For the fragment the data is clearer than you would expect for a research peptide, but only preclinically: the actin-binding site of thymosin beta-4 is required for its angiogenic activity in cell assays and, as a seven-residue peptide, reached nearly the same activity as the whole protein (Philp 2003). In aged mice LKKTETQ promoted wound repair comparably to the parent molecule (Philp 2003, Wound Repair and Regeneration). The review by Sosne (2010) maps the active sites of the protein to their functions and at the same time shows the limit: anti-inflammatory and pro-survival effects depend on other stretches that the fragment does not contain.

BPC-157 has a very large body of animal studies, mostly from one research group. There is hardly any solid human data. The tendon work by Chang (2011) shows the mechanism in fibroblasts, more on that in the single entry.

On the combination there is one comparative study in rats after Achilles tendon repair (Biçer 2026): BPC-157, TB-500 and both together over four weeks. TB-500 had the clearest effect on load to failure and tissue architecture, while BPC-157 alone improved the scores only as a trend. The combination was no better than either agent alone. The authors suspect both feed into the same signalling pathways. Honestly, that means the added value of the mix is mechanism- and experience-based, not study-proven. For the fragment version we know of no combination data at all.

• Generally well tolerated. Most common are local reactions at the injection site: redness, pressure, small bumps.
• Occasionally short-lived fatigue, a feeling of warmth or mild dizziness after the shot is reported.
• Both components promote new vessel formation in animal models. From that a theoretical risk is derived that existing growths could be supplied as well. Evidence is lacking, the point remains part of the discussion in the literature.
• Solid long-term human data does not exist for either component. The fragment mix is even less characterized than the single compounds.
• Do not expect the anti-inflammatory part of full thymosin beta-4 from the fragment, that depends on a stretch TB-500 FRAG does not contain.
• Thymosin beta-4 derivatives are named on the WADA prohibited list. BPC-157 falls under it as a non-approved substance. In competitive sport the blend is off limits.

Before mixing the powder is robust, normal room temperature (around 20 to 25 degrees) is fine, ideally kept in the dark. Unopened it keeps for several months that way, no fridge needed.

After mixing the vial belongs in the fridge (2 to 8 degrees), do not freeze. It stays good there for several months with barely any loss of potency. Over a 4 to 6 week course a 20 mg vial is used up before shelf life becomes an issue anyway.

Swirling or shaking to mix are both fine. Protect from light and do not keep the vial out of the fridge longer than necessary.