Evidence Grade B — Strong clinical evidence. 594 published studies, 325 human. 18 registered clinical trials.
Medically reviewed by a licensed medical professional
Thymosin beta-4 is a naturally occurring protein found in nearly all human cells, involved in cell movement and tissue repair. Pharmaceutical versions have been tested in clinical trials for dry eye disease, corneal wounds, and heart repair after heart attacks, with mixed results. It has no marketing authorisation. It should be distinguished from TB-500, which is a different, smaller fragment.
Thymosin Beta-4 is also known by these brand and alternate names:
594 published studies: 325 human, 210 animal, 106 in-vitro, 61 reviews
Thymosin beta-4 has no current marketing authorisation. RegeneRx Biopharmaceuticals has conducted Phase II and Phase III trials of RGN-259 for dry eye disease and neurotrophic keratopathy, with mixed results. A Phase I cardiac study (RGN-352) demonstrated acceptable safety but did not advance to Phase II.
Animal studies have consistently shown effects on wound healing and tissue repair. The clinical development programme has focused on ophthalmic applications. Thymosin beta-4 should be distinguished from the 7-amino-acid fragment TB-500 (#82), which is a different molecule with no independent clinical trial data.
Research suggests thymosin beta-4's primary biological role is sequestering G-actin, a building block of the cellular skeleton, regulating cell movement and shape. Additional proposed mechanisms from preclinical research include promotion of cell survival, blood vessel formation, and anti-inflammatory effects. These mechanisms have been observed in laboratory and animal studies. Clinical translation remains under investigation.
Research suggests animal studies have consistently shown thymosin beta-4 promotes wound healing and tissue repair across multiple organ systems. Clinical development by RegeneRx Biopharmaceuticals has focused on eye conditions (RGN-259 for dry eye and corneal injuries), with Phase II and Phase III trials producing mixed results. A Phase I cardiac study showed acceptable safety but did not advance. Despite robust animal data, clinical translation has been slow and uncertain. A theoretical concern exists around potential tumour promotion, as the gene encoding thymosin beta-4 is overexpressed in some cancers. The development company appears to have limited resources for large-scale trials.
PeptideTrace tracks 18 registered clinical trials for Thymosin Beta-4 sourced from ClinicalTrials.gov.
Recombinant Human Thymosin Beta 4 for Injection(NL005) for Acute Myocardial Infarction
TB-500 (Thymosin Beta 4 17-23 Fragment) for Cardiovascular Biomarkers in Stable ASCVD
Assessment of the Safety and Efficacy of 0.1% RGN-259 Ophthalmic Solution for the Treatment of NK: SEER-2
Efficacy and Safety Study of Thymosin Beta 4 in Patients With Acute Myocardial Infarction
Safety and Efficacy Study of Thymosin Beta 4 in Patients With Acute Myocardial Infarction.Infarction
Thymosin beta-4 (Tb4) is a naturally occurring 43-amino-acid peptide (MW 4,963 Da), N-terminal acetylated, found in nearly all nucleated cells. Encoded by TMSB4X. Intrinsically disordered in solution. Key domains: actin-binding LKKTETQ (17-23), central alpha-helix (5-16). Developed by RegeneRx as RGN-259 (ophthalmic) and RGN-352 (systemic). No FDA approval.
Research suggests primary role as G-actin sequestering peptide (Kd 0.5-2 microM). Beyond actin: promotes cell survival via AKT/ILK, angiogenesis via VEGF/angiopoietin-1, stem cell migration, anti-inflammatory effects via NF-kappaB suppression. Sulfoxide form (Tb4-SO) activates anti-inflammatory macrophages.
No current marketing authorization. RGN-259 Phase II/III dry eye (N=305): significant corneal staining improvement at Day 28 (P=0.0286). SEER-1 Phase III for neurotrophic keratopathy (N=~80): encouraging but mixed. RGN-352 Phase I for MI: acceptable safety, no Phase II initiated. Animal studies consistently show wound healing, cardiac repair, neuroprotection.
The information on this page is provided for educational and research reference purposes only. This is not medical advice. Always consult a qualified healthcare professional before making any health-related decisions.
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This entry reflects historical nomenclature for the compound more commonly known as BPC-157. The evidence base, regulatory status, and limitations described for BPC-157 (#81) apply identically to this compound. See compound #81 for the full assessment. No marketing authorisation. No human Phase III trials. No established human dosing or safety profile.
Cartalax has no marketing authorisation from any major regulatory agency. No human clinical trials have been conducted. The evidence base consists of cell culture studies published by the originating research group. As with other Khavinson bioregulator peptides, the proposed tissue-targeting mechanisms have not been independently validated. Products available through unregulated channels lack pharmaceutical quality assurance.
TB-500 has no marketing authorisation from any regulatory agency. No human clinical trials of TB-500 specifically have been conducted. The evidence base relies on animal studies of both TB-500 and its parent molecule thymosin beta-4, which are not pharmacologically equivalent. TB-500 is prohibited by WADA and is known from equine and greyhound racing contexts. Products available through unregulated channels lack pharmaceutical quality assurance. The absence of any human safety or efficacy data means that the compound's effects, risks, interactions, and appropriate dosing in humans are unknown.
This content is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before making decisions about your health.
