Research Reference
TB-500
Systemic tissue repair and recovery — the actin-binding fragment
Research & educational purposes only. BioMaxFit does not sell, promote, or represent peptides in any way. We are strictly educational and recommend working with your doctor on anything health-related. The information below comes from published research and documents what has been studied, not what should be done. Many of these compounds are investigational and not approved by the FDA; possession or use outside an authorized clinical trial may be illegal in your jurisdiction. This is not medical advice.
TB-500 is a synthetic 17-amino-acid fragment of Thymosin Beta-4, containing the active actin-binding domain responsible for cell migration and tissue repair. It is a cornerstone of healing peptide protocols, especially when stacked with BPC-157.
No human trials exist for TB-500 specifically. All protocols are extrapolated from Thymosin Beta-4 research and animal studies.
Community-reported protocol: 500 mcg daily in the morning for 8 weeks, then 8 weeks off. TB-500 works systemically, so injection site location does not affect efficacy.
Dosing Reference
Reconstitution
Add 2 mL bacteriostatic water to the 5 mg vial. Resulting concentration: 2.5 mg/mL.
| Dose | Syringe Units | mL Volume | Schedule |
|---|---|---|---|
| 500 mcg | 20 units | 0.2 mL | Daily SubQStandard |
| 750 mcg | 30 units | 0.3 mL | Daily SubQ |
| 1 mg | 40 units | 0.4 mL | Daily SubQ |
| 2 mg | 80 units | 0.8 mL | 2x/week SubQLoading dose (weeks 1-4) |
Math assumes U-100 insulin syringes (1 mL = 100 units). Verify your syringe matches before use. Round half-units to the nearest visible mark.
Reconstitution
Add 2 mL of bacteriostatic water to a 10 mg vial for a concentration of 5,000 mcg/mL. A 500 mcg dose draws to 10 units (0.1 mL) on a U-100 insulin syringe; one vial covers 20 days at the standard protocol.
Gently swirl — do not shake. Refrigerate at 2–8°C and use within 28 days.
Cycling Protocol
The standard cycle is 8 weeks on, 8 weeks off. Tissue remodeling and healing effects build over 4–6 weeks and continue through the full 8-week window. Community protocols describe the off period as allowing receptor sensitivity to reset.
Unlike some peptides, TB-500 protocols use consistent daily dosing throughout the cycle — no loading or tapering needed. The daily protocol is preferred because TB-500's half-life supports once-daily dosing, and consistent levels optimize the cellular repair processes it targets (Kim & Bhatt, 2013).
An enhanced community protocol uses 2–2.5 mg twice weekly (4–5 mg/week total) for those who prefer less frequent injections.
Routes of Administration
Subcutaneous (standard): Inject anywhere convenient — abdomen, thigh, upper arm. TB-500 distributes systemically regardless of site. A 29–31 gauge insulin syringe is commonly used.
Not recommended: Oral (peptide degradation), nasal (no data), topical (molecular weight too large).
Stacking Protocols
| Stack | Components | Purpose | | --- | --- | --- | | Gold Standard Healing | TB-500 500 mcg + BPC-157 500 mcg/day | Cell migration/actin remodeling + angiogenesis | | Healing + GH | TB-500 500 mcg + CJC-1295/Ipamorelin 250/250 mcg | Cell repair + growth hormone stimulation |
Community protocols describe injecting at separate sites when using multiple peptides.
Side Effects & Safety
- Injection site reactions — redness, mild pain, or swelling
- No serious adverse events reported in community use at standard doses
- No human clinical safety data — all safety information from animal studies and community reports
- Fatigue or transient malaise — occasionally reported in the first week
No direct TB-500 human trial data exists to confirm long-term safety or receptor effects.
Research Basis
Community TB-500 dosing is extrapolated from Thymosin Beta-4 research, adjusted for molecular weight differences.
Phase I Human Safety (Ruff et al., 2010): IV doses up to 1,260 mg were well-tolerated in healthy subjects with no dose-limiting toxicities — linear pharmacokinetics across the dose range.
Animal Efficacy Studies: Standard research dose of 6–30 mg/kg in rodents. Cardiac protection documented at 6 mg/kg IV twice weekly (Bock-Marquette et al., 2004).
Scaling logic: TB-500 is the 17–23 amino acid fragment (~845 Da) of full TB-4 (~4,921 Da). Pro-rata scaling from TB-4 protocols of 2–10 mg/week gives 0.34–1.7 mg/week. The community settled on 3.5 mg/week (500 mcg daily) — the midpoint of this range.