TB‑500
Contents
In short
- TB-500 is a synthetic fragment of thymosin beta-4, a protein the body makes itself and uses to repair tissue.
- In animal studies, it supports the growth of new blood vessels and the repair of tissue.
- The full thymosin beta-4 protein has been tested in humans. In a study on leg ulcers, safety was in line with placebo and some ulcers healed faster.
- Thymosin beta-4 has also been tested as eye drops for dry eyes, with less discomfort than placebo.
Fact box
- Type
- Research compound
- Research
- Lab and animal studies
- Sequence
- Ac-Leu-Lys-Lys-Thr-Glu-Thr-Gln
- Other names
- thymosin beta-4 fragment, thymosin beta-4
What is TB-500?
TB-500 is a lab-made fragment of thymosin beta-4, a protein involved in tissue repair. It has drawn interest for possible faster recovery after injuries.
Thymosin beta-4 is a protein found naturally in the body. TB-500 is a shorter, synthetic version based on part of this protein.[1][2]
It helps to know the difference. The studies in humans that are often mentioned were done with the full thymosin beta-4 protein. TB-500 and thymosin beta-4 are not the same substance, so results from one do not automatically apply to the other.
WADA counts both thymosin beta-4 and substances derived from it, such as TB-500, as prohibited growth factors.[3]
The amino acid sequence in the fact box comes from PubChem.[4]
What does the research say about TB-500?
The animal studies are promising. The full thymosin beta-4 protein has shown signs of faster wound healing and less discomfort in dry eyes in small studies in humans. Studies of TB-500 itself in humans are the next step.
| Use | Studies | Research |
|---|---|---|
| Injuries to tendons, muscles and joints | Animal study · Animals | Lab and animal studies |
| Leg ulcers (thymosin beta-4 cream) | 1 study · RCT · n = 73 | Controlled human trials |
| Dry eyes (thymosin beta-4 eye drops) | 1 study · RCT · n = 9 | Early human studies |
| Heart attack (thymosin beta-4) | 1 study · RCT · n = 90 | Early human studies |
RCT means randomised controlled trial. How to read a study
Injuries to tendons, muscles and joints
In animal studies, thymosin beta-4 and TB-500 support the growth of new blood vessels and the repair of tissue. Studies in humans with muscle, tendon or joint injuries are the next step.[5]
Leg ulcers (thymosin beta-4 cream)
In a placebo-controlled phase 2 study with 73 patients with venous leg ulcers, thymosin beta-4 was applied directly to the ulcer. Safety was in line with placebo, and the results suggested that some ulcers may heal faster. About a quarter of the patients had their ulcer fully healed within three months.[6]
Dry eyes (thymosin beta-4 eye drops)
A small phase 2 study with nine patients with severe dry eyes found less discomfort and less damage to the cornea with eye drops containing thymosin beta-4, compared with placebo.[7]
Heart attack (thymosin beta-4)
A phase 2 study with 90 patients with acute heart attack has tested thymosin beta-4. The study is registered as completed.[8] We have not found published results yet.
Questions and answers about TB-500
Is TB-500 the same as thymosin beta-4?
No. TB-500 is a synthetic fragment of thymosin beta-4. The studies in humans were done with the full protein.
Does TB-500 help with sports injuries?
The animal studies are promising, and studies in humans are the next step.