TB-500 and Tendinopathy: What Has Been Studied

What the research covers

No human study of TB-500 for tendinopathy was found. Its key ingredient is a lab-made copy of a short piece of thymosin beta-4, a larger natural protein. The piece is 7 amino acids long.

One rodent (rat) study tested it on tendons. The team cut and repaired the Achilles tendon in 32 animals. For 4 weeks, groups got TB-500, BPC-157, both, or no peptide. The TB-500 dose was 60 micrograms per kg a day, into the belly cavity. Tendons in that group were stronger than control tendons, and their tissue scores were better. Both differences were significant. Adding BPC-157 gave no extra benefit. The authors called the results early and asked for longer studies.

A 2024 lab paper said the effects of TB-500 itself have not been documented. In its cell tests, only one of its breakdown pieces helped close a wound.

The rodent (rat) tendons were fresh cuts made on purpose. None had long-standing tendinopathy. A PubMed search on 27 September 2026 found no study that gave TB-500 to people. It found no trial of thymosin beta-4 for tendon problems either.

Sources

1. Bicer O, Adanir O, Guleryuz Y, et al. Effects of BPC-157 and TB-500 on Achilles tendon healing in rats: A histopathological and biomechanical study. Jt Dis Relat Surg (2026). PMID 42542926 doi:10.52312/jdrs.2026.2951 Rodent (rat), 32 animals, repaired Achilles tendon; TB-500 60 micrograms per kg a day intraperitoneally for 4 weeks; stronger tendons, better tissue scores; no added benefit with BPC-157.
2. Rahaman KA, Muresan AR, Min H, et al. Simultaneous quantification of TB-500 and its metabolites in in-vitro experiments and rats by UHPLC-Q-Exactive orbitrap MS/MS and their screening by wound healing activities in-vitro. J Chromatogr B Analyt Technol Biomed Life Sci (2024). PMID 38382158 doi:10.1016/j.jchromb.2024.124033 Rodent (rat) and cell study; states TB-500 effects are undocumented; only the breakdown piece Ac-LKKTE showed wound-healing activity in cells.
3. Ho EN, Kwok WH, Lau MY, et al. Doping control analysis of TB-500, a synthetic version of an active region of thymosin beta(4), in equine urine and plasma by liquid chromatography-mass spectrometry. J Chromatogr A (2012). PMID 23084823 doi:10.1016/j.chroma.2012.09.043 Identifies the key ingredient of TB-500 as acetylated LKKTETQ, the 17-23 segment of thymosin beta-4.
4. Esposito S, Deventer K, Goeman J, et al. Synthesis and characterization of the N-terminal acetylated 17-23 fragment of thymosin beta 4 identified in TB-500, a product suspected to possess doping potential. Drug Test Anal (2012). PMID 22962027 doi:10.1002/dta.1402 Chemical analysis identifying Ac-LKKTETQ, the acetylated 17-23 fragment of human thymosin beta-4, in TB-500.