Also known as:TB500· spacing variantThymosin beta-4 fragment· expanded description
Woundtissue-repair research…
TB-500
Evidence levelHuman evidence
Human evidenceNone established
Regulatory statusNot FDA-approved
What you need to know in 20 seconds
What is it?
Synthetic fragment of thymosin beta-4
Research focus
Wound/tissue-repair research claims
Human evidence
No verified human drug-product exposure or therapeutic outcome dataset for the TB-500 fragment was identified. A 2026 rat Achilles-tendon study provides direct preclinical evidence for the fragment. A ClinicalTrials.gov-style TB-500 record encountered during research explicitly states that it is fictional/example content and is not counted.
Regulatory status
Not FDA-approved; FDA has reviewed TB-500-related substances in the compounding context and highlights safety/data gaps.
Main limitations
Human injury-recovery efficacy, human dosing, pharmacokinetics, long-term safety or comparative benefit.
Safety
Potential immunogenicity and peptide-related impurities; safety of human administration is not established.
i
No verified human drug-product exposure or therapeutic outcome dataset for the TB-500 fragment was identified. A 2026 rat Achilles-tendon study provides direct preclinical evidence for the fragment. A ClinicalTrials.gov-style TB-500 record encountered during research explicitly states that it is fictional/example cont…
What the evidence actually supports
✓Publish prominently as an evidence-gap page; do not use parent-molecule trial results as TB-500 proof.
✓Preserve FDA's human-data gap and add registry-integrity warning.
✓Direct preclinical evidence, clearly separated from human claims.
What is not established / key limitations
×Absence of direct human exposure data is itself the central finding.
×A ClinicalTrials.gov record NCT07487363 must NOT be counted: the record itself explicitly states it is a fictional/example study.
×Animal results do not establish human tendon healing.
Selected study & evidence records
FDA evidence audit: TB-500 (thymosin beta-4 fragment LKKTETQ) human exposure
2026 · Regulatory evidence review / no human exposure identified
FDA states it has not identified human exposure data for drug products containing the TB-500 fragment.
Potential immunogenicity and peptide-related impurities; safety of human administration is not established.
Human adverse effects, pharmacokinetics and long-term safety are not established; FDA highlights potential immunogenicity, aggregation and peptide-impurity concerns.
Technical details
Mechanism / biologyMarketed TB-500 is understood by FDA as a seven-amino-acid thymosin beta-4 fragment; biological claims are often extrapolated from full-length thymosin beta-4.
Route / formulation boundaryTB-500 fragment evidence must remain separate from full-length thymosin beta-4 and from fictional/example registry content.
Identity / data-quality noteDo not count NCT07487363 as human evidence; the registry record identifies itself as fictional/example content.
Dosing evidence statusDosing research conclusion recorded. No direct human drug-exposure regimen identified. FDA states it has not identified human drug-product exposure data for the TB-500 fragment.
Evidence rule: WhichPeps keeps human, animal, laboratory, regulatory and product/formulation evidence distinct. Common names help people find the page; they do not change the underlying scientific identity.
