Research CompoundSubQ · Healing

TB4-FRAG

Thymosin Beta-4 Fragment (17-23) — Ac-SDKPDM-NH2

Half-life
~4-8 hours
Route
SubQ
Typical dose
500 mcg–2 mg/day
Reconstitutable
Yes

What is TB4-FRAG?

TB4-FRAG is a synthetic fragment of Thymosin Beta-4 comprising the actin-binding sequence (amino acids 17-23). It is the minimal active fragment that retains TB-500's wound healing and anti-inflammatory properties. It is sometimes used as a more cost-effective alternative to full TB-500 in healing protocols.

The 17-23 fragment contains the LKKTET actin-binding sequence responsible for TB-500's core biological activity. By binding actin monomers, TB4-FRAG promotes cell migration, wound closure, and anti-inflammatory signaling through the same pathway as full TB-500, at a fraction of the molecular weight. Some research suggests the fragment may be more bioavailable than the full 43-amino acid protein.

Research Evidence

SilverWound Healing

Animal studies confirm the 17-23 fragment retains wound healing activity of full thymosin beta-4, including reduced inflammation and accelerated tissue repair.

BronzeRelative to TB-500

Community protocols use TB4-FRAG as a cost-effective alternative or adjunct to TB-500. Limited direct comparison data between the fragment and full protein in healing outcomes.

Evidence grades: Gold = RCT human data · Silver = consistent animal/human data · Bronze = limited or preliminary

Dosing Protocols

Standard dose
500 mcg–2 mg/day
Community protocols vary widely. Lower doses (500mcg) used for maintenance, higher doses (2mg) for acute injury.
Cycle length
4–8 weeks
Same cycle structure as TB-500. No HPTA suppression, no PCT required.

Reconstitution Guide

Vial SizeBAC WaterConcentrationTarget draw
5 mg5 ml1 mg/ml1mg = 100 units
10 mg5 ml2 mg/ml1mg = 50 units
Calculate your exact protocol →

Frequently Asked Questions

Is TB4-FRAG the same as TB-500?

No. TB-500 is a synthetic version of the full Thymosin Beta-4 protein (43 amino acids). TB4-FRAG is just the active fragment (amino acids 17-23, the actin-binding LKKTET sequence). The fragment retains the core wound healing mechanism at lower molecular weight and potentially higher bioavailability, but is not identical in its complete biological activity profile.

Can TB4-FRAG and BPC-157 be stacked?

Yes — this is a common budget alternative to the full Wolverine Protocol (TB-500 + BPC-157). TB4-FRAG provides the systemic actin-based healing mechanism and BPC-157 provides local VEGF-driven tissue repair. The combination covers similar complementary mechanisms at a lower cost than full TB-500.

References

  1. [1]Goldstein AL, Hannappel E, Kleinman HK. Thymosin beta-4: actin-sequestering protein moonlights to repair injured tissues. Trends Mol Med. 2005;11(9):421-429.
  2. [2]Sosne G, Qiu P, Goldstein AL, Wheater M. Biological activities of thymosin beta4 defined by active sites in short peptide sequences. FASEB J. 2010;24(7):2144-2151.
Disclaimer: This profile is for informational and research purposes only. Not medical advice. Always consult a licensed healthcare provider before using any compound.

This profile was prepared using AI-assisted research synthesis. Citations are provided where applicable — verify with primary sources before clinical application.

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