What it is
TB-500 is a synthetic peptide related to thymosin beta-4, a 43-amino-acid actin-sequestering protein released by platelets at sites of injury. Thymosin beta-4 appears in research on dermal wound repair, corneal surface disease, and cardiac injury. TB-500 itself is supplied as research material and is not an approved medicine.
How it works
Thymosin beta-4 binds monomeric G-actin and is thought to promote cell migration, angiogenesis, and survival signalling, in part by forming a complex with PINCH and integrin-linked kinase that activates Akt.
Regulatory status
- Cosmetic ingredient
- Research compound
- In clinical trials
- Approved medicine
Not approved as a medicine by the FDA or the EMA. Some are registered in individual countries. Supplied for laboratory research only.
What published research is studying
- Dermal wound healing in rodent full-thickness wound models
- Severe dry eye disease and corneal epithelial repair (Phase 2 and Phase 3 trials)
- Pressure ulcers and venous stasis ulcers (Phase 2 trials)
- Cardiomyocyte survival and cardiac repair after coronary artery ligation (preclinical)
Key findings
In a 56-day Phase 2 randomised, double-masked trial in 9 patients with severe dry eye, the thymosin beta-4 group showed a 35.1% greater reduction in ocular discomfort and a 59.1% greater reduction in total corneal fluorescein staining than vehicle at day 56.
Sosne G et al., Cornea 2015In a rat full-thickness wound model, thymosin beta-4 increased re-epithelialisation by 42% at 4 days and by as much as 61% at 7 days compared with saline controls, with greater wound contraction and collagen deposition.
Malinda KM et al., J Invest Dermatol 1999After coronary artery ligation in mice, thymosin beta-4 upregulated integrin-linked kinase and Akt activity in the heart, enhanced early myocyte survival, and improved cardiac function.
Bock-Marquette I et al., Nature 2004A review of two Phase 2 trials in stasis and pressure ulcers reported that, among patients whose ulcers healed, healing was accelerated by almost a month relative to control.
Treadwell T et al., Ann N Y Acad Sci 2012
What the studies measured
Study durations
- Phase 2 severe dry eye trial: 28 days of dosing with follow-up through day 56 (NCT01393132).
- Phase 2 pressure ulcer study: safety and tolerability assessed over up to 84 days (NCT00382174).
- Rat full-thickness wound model: re-epithelialisation measured at 4 and 7 days after wounding (Malinda et al., 1999).
Endpoints
- Ocular discomfort score (OSDI questionnaire)
- Corneal fluorescein staining (NEI grading)
- Tear film breakup time and tear volume
- Rate of re-epithelialisation and wound contraction
- Cardiac function after coronary ligation
How strong is the evidence?
Human trials exist for full-length thymosin beta-4 in dry eye and chronic wounds, several of them small, while the shorter TB-500 fragment sold as research material has no published human trials of its own.
Common questions
Is TB-500 an approved medicine?
Research compound. Not approved as a medicine by the FDA or the EMA. Some are registered in individual countries. Supplied for laboratory research only.
How much human research is there on TB-500?
Human trials exist for full-length thymosin beta-4 in dry eye and chronic wounds, several of them small, while the shorter TB-500 fragment sold as research material has no published human trials of its own.
Does UU supply TB-500?
Yes, as premium-grade research material for laboratory use. Every batch is tested by an independent lab and the certificate of analysis is published.