Cat 1 — 2026Recovery

TB-500

Thymosin Beta-4 fragment

Synthetic fragment of Thymosin Beta-4. Promotes systemic tissue repair through actin regulation and stem cell activation. Often stacked with BPC-157.

Evidence

Human data exists

Routes

injectable

Available since

Derived from Thymosin Beta-4 research (1960s); synthetic fragment research use widely studied from 2000s onward

Mechanism of action

Promotes actin polymerization critical for cell migration and tissue repair. Activates stem cell recruitment to injury sites, reduces inflammatory cytokines TNF-α and IL-6, enhances angiogenesis and neurogenesis systemically.

Effects in the body

TB-500 is systemic in scope — it works throughout the entire body. The actin regulation mechanism means it affects virtually every cell that needs to migrate during healing. Works synergistically with BPC-157 for comprehensive repair protocols.

Pros & cons (from the literature)

Pros

Systemic reach — whole-body repair signaling
Reduces inflammation AND scar tissue formation
Supports muscle, tendon, ligament, and cardiac tissue repair
Strong preclinical data across multiple tissue types
Synergistic with BPC-157

Cautions

Accelerated dormant tumor growth found in some animal models — significant concern
No completed human clinical trials
Immunogenicity risks not fully characterized
May disrupt immune response in certain scenarios
Optimal human dosing not established

Protocol summary (from published research)

2–2.5 mg twice weekly subcutaneous for 4–6 weeks, then 2 mg/month maintenance dosing in research protocols. Frequently studied in combination with BPC-157 at a 1:1 ratio.

Dosing ranges reproduced from published research literature. Not a prescription, not medical advice.

FDA & regulatory status

Returned to Category 1 in February 2026. Compoundable with a physician prescription from licensed 503A pharmacy. The full Thymosin Beta-4 molecule has been studied in cardiac repair clinical trials (PledOx).

Evidence base

Strong preclinical data. Full TB4 molecule in human cardiac and dry eye clinical trials. No completed human trials specifically for TB-500 fragment.

Primary research sources

Peer-reviewed literature referenced throughout this profile is drawn from PubMed, Cell Metabolism, and clinical trial registries cited in the evidence base above.

Expert perspective — Dr. Alex Tatem, Urologist

Dr. Alex Tatem is a board-certified Urologist and Men's Health Specialist who has studied peptides for 12 years. Videos featured for educational purposes. ThePeptide.expert is an independent platform.

Dr. Tatem covers TB-500 as part of his comprehensive breakdown of the recovery peptide stack and the FDA regulatory landscape in 2026.

Important. ThePeptide.expert summarizes published research. We are not a pharmacy, do not prescribe, and make no therapeutic claims. Regulatory status varies by jurisdiction.