Peptide Graded

TB-500

Is TB-500 legal in the US?

No. It is not approved and is sold as a research chemical.

CAnimal and cell studiesNot approvedas of 2026-10-26

TB-500 is not approved by the FDA for any use and is sold as a research chemical. In July 2026 an FDA advisory committee voted to recommend it for the list of substances pharmacies may compound, but that recommendation has not become a rule and is not an approval. 710

It is not approved for any use. Selling it as a research chemical is how vendors avoid drug rules. But marketing it for human injection is unlawful. In July 2026 an FDA advisory committee recommended adding it to the list pharmacies may compound from. That still requires FDA rulemaking. 710

Read the full TB-500 page

More on TB-500

Citations

  1. Goldstein 2012, Expert Opin Biol Ther: Thymosin beta4, a multifunctional regenerative peptide doi.org
  2. McDermott Will & Emery 2026: PCAC backs majority of peptides in two-day public meeting mcdermottlaw.com
  3. Guarnera 2007, Ann N Y Acad Sci: Thymosin beta-4 and venous ulcers, a European randomized study pubmed.ncbi.nlm.nih.gov
  4. Sosne 2022, Int J Mol Sci: RGN-259 ophthalmic solution in neurotrophic keratopathy, phase 3 pubmed.ncbi.nlm.nih.gov
  5. Goldstein 2007, Ann N Y Acad Sci: Thymosin beta4 overview doi.org
  6. Esposito 2012, Drug Test Anal: Synthesis and characterization of the 17-23 fragment identified in TB-500 pubmed.ncbi.nlm.nih.gov
  7. FDA: Certain bulk drug substances for use in compounding may present significant safety risks fda.gov
  8. Ho 2012, J Chromatogr A: Doping control analysis of TB-500 in equine urine and plasma pubmed.ncbi.nlm.nih.gov
  9. 2025, Drug Test Anal: Equine doping controls of thymosin beta 4, a population study pubmed.ncbi.nlm.nih.gov
  10. STAT 2026: FDA peptide compounding panel backs epitalon, rejects emideltide statnews.com

Reference information only, not medical advice. Drawn from the TB-500 article, fact-checked against the cited sources. No dosing anywhere on this site.