What is TB-500?
TB-500 is a synthetic peptide corresponding to an active region of thymosin beta-4 (TB-4), a protein your body produces that plays a role in actin regulation, cell migration, and tissue repair.
It’s commonly studied in the context of injury recovery and is one of the most popular peptides in the recovery space, frequently mentioned alongside BPC-157.1
Benefits & what it’s studied for
Preclinical research suggests roles in cell migration and tissue healing.
Studied for connective-tissue repair and recovery, often in animal models.
Early research points to anti-inflammatory effects. Human clinical data is limited — most evidence is animal or lab-based, so we grade it Emerging.
How does TB-500 work?
TB-500 is thought to work largely through actin regulation — promoting cell migration, blood-vessel formation, and the movement of repair cells to injured tissue. This is the proposed basis for its tissue-repair effects.5
Dosing & administration
Research and clinical use describe subcutaneous injection.6
This is educational, not medical advice. We don’t publish dosing. Specific dosing should be determined by a licensed provider after evaluation.
Risks, side effects & safety
Reported effects include injection-site reactions, fatigue, and head-rush/flushing sensations; long-term safety data in humans is limited. As with all repair peptides, theoretical concerns about effects on abnormal cell growth mean people with a cancer history should avoid it without specialist guidance.7
Legality & status
TB-500 was removed from Category 2 in April 2026 and is scheduled for PCAC review on July 23, 2026. Off Category 2 ≠ 503A-compoundable ≠ FDA-approved — three separate things, and this is actively moving. Confirm current status with a licensed provider.3 See the full picture in our legality explainer.
Regulatory status as of June 2026 — reconfirm against the live FDA 503A list before go-live.
Thinking about TB-500?
Talk to a licensed provider who can tell you if it fits your goals — and build a safe protocol.
Research & references
- 1Thymosin beta-4 / TB-500 biology — actin regulation & repair. Link to be finalized. link pending
- 2Preclinical tissue/wound-repair studies. Link to be finalized. link pending
- 3FDA — April 2026 Category 2 removal; PCAC July 23, 2026 docket; FDA-2025-N-6895. Confirm at publish. link pending
- 4Anti-inflammatory effects (early research). Link to be finalized. link pending
- 5Mechanism literature (actin / cell migration / angiogenesis). Link to be finalized. link pending
- 6Clinical dosing literature (loading/maintenance). Link to be finalized. link pending
- 7TB-500 safety / tolerability literature. Link to be finalized. link pending
Reference links are illustrative placeholders — replace with verified PubMed/journal URLs before publishing.
Frequently asked questions
What is TB-500 used for?+
It’s studied mainly in preclinical models for tissue repair, recovery, and reducing inflammation.
Is TB-500 the same as thymosin beta-4?+
TB-500 is a synthetic peptide based on an active region of the natural protein thymosin beta-4, not the full protein.
Is TB-500 legal?+
It came off Category 2 in April 2026 and is under PCAC review in July 2026 — but that’s not FDA approval. Status is evolving; confirm with a provider.
Does TB-500 have human studies?+
Most evidence is from animal and laboratory research; human clinical data is limited, which is why we grade it Emerging.