Thymosin Beta-4

TB-4 · Tβ4 · Full-length Thymosin Beta-4

Rank#999
Tissue RepairCategory 2Phase IIIResearchSubQIM

Popular for:Full-length healing peptide, wound repair, cardiac repair, more complete than TB-500

592

Total Studies

324

Human Studies

Phase III

Evidence Level

Category 2

FDA Status

Overview

Thymosin Beta-4 (TB-4) is the full-length 43-amino acid peptide naturally found in high concentrations in wound fluid, blood platelets, and many tissues throughout the body. It plays a crucial role in tissue repair, wound healing, cell migration, angiogenesis, and anti-inflammation.

TB-4 is the parent molecule from which TB-500 is derived — TB-500 is a synthetic fragment containing the active region (amino acids 17-23) responsible for actin binding and cell migration. The full-length TB-4 includes additional sequences that activate cardiac progenitor cells and hair follicle stem cells, making it more biologically complete for regenerative applications.

Mechanism of Action

Thymosin Beta-4's primary mechanism involves sequestering G-actin monomers, which regulates actin polymerization and cell motility. This promotes cell migration into wound sites. TB-4 also upregulates anti-inflammatory factors, promotes angiogenesis, and activates cardiac progenitor cells (unique to the full-length version). The LKKTET sequence (contained in TB-500) handles actin binding, while other regions of TB-4 handle cardiac and follicular stem cell activation.

Key Research Benefits

More biologically complete than TB-500 fragment
Studied for cardiac repair and regeneration after myocardial infarction
Researched for corneal wound healing (Phase II trials by RegeneRx)
Promotes hair follicle stem cell activation (not in TB-500)
Anti-inflammatory and pro-angiogenic properties
Extensively studied in wound healing models

Clinical Evidence Summary

Research Pipeline

Preclinical
Animal
Phase I
Phase II
Phase III
Approved

592

Total Studies

324

Human Studies

FDA Category 2. Was in Phase II clinical trials by RegeneRx Biopharmaceuticals for corneal and cardiac repair. Research compound. Potential Category 1 reinstatement under RFK announcement.

Key Studies / PubMed References

592 studies found on PubMed · showing top 25 by relevance

View all on PubMed

Thymosin Beta-4 Modulates Cardiac Remodeling by Regulating ROCK1 Expression in Adult Mammals.

In Vitro

Maar K, Thatcher JE, Karpov E, et al. · International journal of molecular sciences · 2025

PMID: 40362372

Thymosin beta 4 as an Alzheimer disease intervention target identified using human brain organoids.

Human Study

Zeng PM, Sun XY, Li Y, et al. · Stem cell reports · 2025

PMID: 40816274

Recombinant human thymosin beta 4 improves ischemic cardiac dysfunction in mice and patients with acute ST-segment elevation myocardial infarction after reperfusion.

Human Study

Zhang Y, Dong Q, Bian X, et al. · Cardiovascular research · 2025

PMID: 41229390

Identification of glutamine as a potential therapeutic target in dry eye disease.

In Vitro

Chen X, Zhang C, Peng F, et al. · Signal transduction and targeted therapy · 2025

PMID: 39837870

Thymosin βand βExpression in Human Organs during Development: A Review.

Review

Faa G, Messana I, Coni P, et al. · Cells · 2024

PMID: 38994967

Side Effects & Safety

Generally well-tolerated in clinical trials
Injection site reactions
Headache
Potential concern with promoting growth in existing tumors (theoretical)
More expensive than TB-500 fragment

Known Interactions

No curated interaction entry is live for Thymosin Beta-4 yet.

Until the interaction table is fully populated, use the interaction checker and related peptides below to explore adjacent compounds and likely research pairings.

Frequently Asked Questions

Research Disclaimer

This page is for research and educational purposes only. The information presented is based on published scientific literature and does not constitute medical advice, diagnosis, or treatment recommendations. Thymosin Beta-4 is not approved by the FDA for human therapeutic use. Always consult a qualified healthcare professional before making any health-related decisions. The studies referenced are linked to their original PubMed sources for verification.