Is TB-500 approved or legal?

TB-500 is not approved by the FDA (or other major regulators) for human use; it is sold only as a research chemical. Full-length Thymosin Beta-4 has been studied in clinical trials for eye and cardiac indications but is not an approved consumer product. TB-500 is also banned in competitive sport under WADA. Legality of possession varies by jurisdiction.

What is the half-life of TB-500, and how often is it dosed?

Full-length recombinant Tβ4 showed a short plasma terminal half-life of roughly 0.5-2 hours after IV dosing in a Phase I study, though tissue effects may persist longer. The half-life of the subcutaneous 'TB-500' fragment is not well characterized in humans. Anecdotal community protocols dose a few times per week during a loading phase, then taper — but this is not clinically validated.

Does TB-500 actually heal injuries in humans?

Strong preclinical (animal/in-vitro) data show Tβ4 promotes wound healing, angiogenesis, and tissue repair, and some human eye trials are positive. However, there are no completed, published human randomized trials proving TB-500 heals tendon, ligament, muscle, or joint injuries. Recovery claims remain largely anecdotal.

How is TB-500 typically administered?

Research and investigational use has involved intravenous infusion, topical/ophthalmic drops, and other routes. Community use is most commonly reported as subcutaneous injection, sometimes intramuscular near a target injury. This is research-reference information, not a usage recommendation.

Is TB-500 the same as Thymosin Beta-4?

Not exactly. Thymosin Beta-4 is the full 43-amino-acid natural peptide. 'TB-500' usually refers to a synthetic shorter fragment containing the active actin-binding region. They share mechanism but may differ in potency and pharmacokinetics, and product identity in the research-chemical market is inconsistent.

Recovery

TB-500

Also known as: Thymosin Beta-4, TB4, Tβ4

Synthetic actin-binding peptide studied for tissue repair; strong preclinical data but limited human evidence for musculoskeletal use.

Last updated July 11, 2026

Reconstitute this peptide Buy TB-500

Overview

TB-500 is a synthetic peptide widely marketed as a fragment/analog of Thymosin Beta-4 (Tβ4), a naturally occurring 43-amino-acid protein found in platelets, white blood cells, and other tissues that plays a central role in cell migration, actin regulation, and tissue repair. The injectable products sold as "TB-500" typically contain a short active fragment of Tβ4 (often the actin-binding region) rather than the full-length protein, though labeling and purity vary widely in the research-chemical market. Most of the rigorous evidence comes from full-length Tβ4 in animal models and a handful of company-sponsored human trials in specific indications such as corneal/eye injury, dry eye, and cardiac repair. Evidence specifically for the "TB-500" fragment in athletic recovery, tendon, ligament, or muscle injury is largely preclinical or anecdotal. It is sold strictly as a research chemical and is not approved for human therapeutic use in recovery or performance contexts. It is also banned in competitive sport. This profile is provided for research reference only and is not medical advice.

How it works

Thymosin Beta-4 is a primary intracellular G-actin sequestering peptide: it binds monomeric actin and regulates actin polymerization, which governs cell motility. Through this and related pathways, Tβ4 promotes the migration of fibroblasts, endothelial cells, keratinocytes, and stem/progenitor cells to sites of injury. Preclinical work attributes its repair activity to several effects: stimulating angiogenesis (new blood vessel formation), reducing inflammatory cytokine signaling, decreasing apoptosis in injured tissue, and increasing collagen deposition during wound healing. The "TB-500" fragment is thought to retain the actin-binding and cell-migration-promoting properties, but the relative potency of fragment versus full-length peptide in humans is not well characterized.

Researched effects

Clinical Promotes corneal epithelial wound healing and improves dry eye signs/symptoms
Clinical Well tolerated with no dose-limiting toxicities in early-phase intravenous human safety studies
Preclinical Accelerates dermal and full-thickness wound healing, including in diabetic and steroid-treated models
Preclinical Promotes angiogenesis and increases collagen deposition at injury sites
Preclinical Supports cardiac cell survival and repair after myocardial infarction
Anecdotal Reduces inflammation and supports tendon, ligament, and muscle recovery
Anecdotal Improves flexibility and reduces injury-related pain in athletes

Evidence levels: Clinical (human trials) · Preclinical (animal/lab) · Anecdotal (community-reported).

Dosing reference

For research reference only — not a recommendation.

Clinical / studied dosing

No established clinical dosing for recovery/musculoskeletal use in humans. Investigational use of full-length recombinant Tβ4 in a first-in-human Phase I study used single intravenous doses escalated from 0.05-25 ug/kg and a multiple-dose arm of 0.5-5.0 ug/kg IV daily for 10 days. Eye indications have used a topical 0.1% ophthalmic solution (RGN-259). These are research settings only and do not translate to the subcutaneous protocols used by the community.

Community-reported dosing (anecdotal)

ANECDOTAL — research reference only, not medical advice or instruction. Community write-ups and forum/Reddit-style guides commonly describe a loading phase of roughly 4-8 mg per week (split into 2-3 subcutaneous injections) for the first 4 weeks, followed by a maintenance phase of about 2-4 mg every 1-2 weeks, over a 6-8 week cycle (sometimes extended to ~12 weeks for chronic issues). Subcutaneous injection into abdominal fat or flank is most often reported; some report intramuscular injection near a target injury. TB-500 is frequently stacked with BPC-157 in anecdotal recovery protocols. These figures are unverified, vary widely, and are not supported by controlled human dosing trials.

Half-life: Full-length recombinant Tβ4 showed a short plasma terminal half-life of ~0.5-2 hours after IV dosing in a Phase I study; tissue/biological effects may outlast plasma levels. Half-life of the subcutaneous 'TB-500' fragment in humans is not well characterized.
Routes: subcutaneous, intramuscular, topical, nasal

Safety & side effects

Human safety data is limited and largely from investigational full-length Tβ4. Early-phase IV studies in healthy volunteers reported only mild-to-moderate adverse events, no serious adverse events or dose-limiting toxicities, and minimal immunogenicity. Community-reported side effects (anecdotal) include transient fatigue/lethargy, mild headache, injection-site irritation, and water retention when stacked with growth-hormone secretagogues. Because TB-500 is sold as an unregulated research chemical, product identity, purity, and sterility are not guaranteed, which is a meaningful real-world risk. Theoretical concerns about pro-angiogenic peptides and tumor growth have not been resolved in long-term human data. TB-500 is prohibited in competitive sport under WADA. Not approved for human use; consult a qualified clinician before any use.

Research summary

The strongest evidence for Thymosin Beta-4 lies in its well-described biology as a G-actin-binding peptide that drives cell migration, angiogenesis, anti-inflammatory effects, and tissue repair, supported by a large body of animal and in-vitro work across dermal wounds, cornea, heart, and nervous tissue. Human clinical data exists chiefly for company-sponsored programs: ophthalmic Tβ4 (RGN-259) showed benefit for corneal epithelial healing in some Phase II/III trials but failed a key European Phase III endpoint, and a first-in-human IV Phase I study established a favorable short-term safety profile with a short plasma half-life. Crucially, the marketed "TB-500" fragment used for athletic recovery has not been validated in completed, published human randomized trials for tendon, ligament, muscle, or joint repair. Benefits in that context rest on mechanistic plausibility, animal data, and anecdote rather than controlled human efficacy outcomes. Overall, TB-500 is a biologically interesting peptide with genuine preclinical promise and reassuring early human safety signals in specific indications, but the recovery and performance claims that drive its popularity remain unproven in humans. Combined with research-chemical quality risks and its prohibited status in sport, it warrants cautious, evidence-graded interpretation and a research-use-only framing.

FAQ

Is TB-500 approved or legal?: TB-500 is not approved by the FDA (or other major regulators) for human use; it is sold only as a research chemical. Full-length Thymosin Beta-4 has been studied in clinical trials for eye and cardiac indications but is not an approved consumer product. TB-500 is also banned in competitive sport under WADA. Legality of possession varies by jurisdiction.
What is the half-life of TB-500, and how often is it dosed?: Full-length recombinant Tβ4 showed a short plasma terminal half-life of roughly 0.5-2 hours after IV dosing in a Phase I study, though tissue effects may persist longer. The half-life of the subcutaneous 'TB-500' fragment is not well characterized in humans. Anecdotal community protocols dose a few times per week during a loading phase, then taper — but this is not clinically validated.
Does TB-500 actually heal injuries in humans?: Strong preclinical (animal/in-vitro) data show Tβ4 promotes wound healing, angiogenesis, and tissue repair, and some human eye trials are positive. However, there are no completed, published human randomized trials proving TB-500 heals tendon, ligament, muscle, or joint injuries. Recovery claims remain largely anecdotal.
How is TB-500 typically administered?: Research and investigational use has involved intravenous infusion, topical/ophthalmic drops, and other routes. Community use is most commonly reported as subcutaneous injection, sometimes intramuscular near a target injury. This is research-reference information, not a usage recommendation.
Is TB-500 the same as Thymosin Beta-4?: Not exactly. Thymosin Beta-4 is the full 43-amino-acid natural peptide. 'TB-500' usually refers to a synthetic shorter fragment containing the active actin-binding region. They share mechanism but may differ in potency and pharmacokinetics, and product identity in the research-chemical market is inconsistent.

References

All content is for research and educational use only and is not medical advice. Products are sold for laboratory research only and are not for human consumption.