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Thymosin Beta-4 Fragments
Also known as Ac-SDKP, TB4 fragments, N-terminal fragment.
Best known for Sub-fragments used as alternatives to TB-500
Evidence★☆☆☆☆
Safety dataLargely unknown
Route Injectable
United StatesNot approved
AustraliaThymosin Beta 4 named in Appendix D cl.5
as at 16 September 2026
What it is and what it does
This entry covers shorter fragments of Thymosin Beta-4, most notably Ac-SDKP, a four-amino-acid N-terminal fragment. They are at a preclinical stage of research, not approved, and commonly discussed as alternatives to TB-500.
What the full entry covers
The book carries the rest of this entry:
- Where the research stands, with every claim cited
- What people commonly ask, and what the research shows so far
- Dosing in four labelled bands, described and not recommended
- Side effects, serious risks, cautions and interactions
- Questions to discuss with your doctor
- How it compares with TB-500, Thymosin Beta-4, BPC-157
Related entries
A certificate of analysis tells you what is in a vial. The evidence rating above tells you whether the compound has been shown to work in humans. Neither answers the other's question. How to read a certificate of analysis.
This page describes what is known and not known about Thymosin Beta-4 Fragments. It is not medical advice and not a recommendation to use it.