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This entry or formulation may be investigational and may not correspond to an FDA-approved product; safety and efficacy may not have been established. Kairo lists it for identification and record-keeping only.
Overview
Product & regulatory status
Research entry: inclusion is for identification, not approval or a recommendation to use it. Verify the exact product and current US status with a pharmacist.
What the evidence shows
Severe dry eye · small randomized study
A nine-patient phase 2 study reported improvement in selected eye symptoms and staining measures after an ophthalmic preparation. The very small sample and eye-specific endpoints limit conclusions about other formulations or tissues. [1]
Larger dry-eye trial · primary endpoints not met
A separate randomized trial enrolled 72 participants. Neither primary endpoint—ocular discomfort or inferior corneal staining at the prespecified visit—significantly differed from placebo. Some secondary measures improved. Positive secondary findings should be read alongside the negative primary results. [2]
What remains unknown
Eye-drop trials do not establish systemic injury recovery, benefit for a different diagnosis, or safety of injectable products. Full-length thymosin beta-4 and the TB-500 fragment must be distinguished.
Safety
Formulation matters
The FDA fragment safety summary concerns TB-500; it is not a safety assessment of every full-length formulation. [3]
Ophthalmic research is formulation-specific
The cited trials studied an eye-drop preparation, not home-reconstituted injections. Their manufacturing and administration context cannot be used as a general handling recipe. [2]
Understanding product quality
Compounded drugs are not FDA-approved finished products. Poor preparation can cause contamination or incorrect strength. A catalog entry or a research paper is not a quality assessment of your product. [4]
When to seek urgent help
Severe allergic symptoms such as trouble breathing, throat or tongue swelling, or fainting need immediate help. Call 911 or your local emergency number. This is general emergency information, not a complete list of risks for this compound. [5]
A starting point for discussion
This is not a complete list of adverse effects or interactions. Your health history, other medicines, and the exact formulation matter. Missing safety data is not evidence of safety.
Common questions
Why can a paper sound positive when primary endpoints were negative?
Researchers may report promising secondary measurements. Those can generate hypotheses, but should not replace the main question the trial was designed to answer.
Questions for your clinician
Does the evidence match my condition and this exact product? What risks or interactions matter for me? How would we assess whether it is helping?
Sources
- Thymosin β4 significantly improves signs and symptoms of severe dry eye in a phase 2 randomized trial2015 · small randomized eye-drop trial · 9 participants
- Thymosin beta 4 ophthalmic solution for dry eye: a randomized, placebo-controlled, Phase II clinical trial conducted using the controlled adverse environment (CAE) model2015 · randomized eye-drop trial · 72 participants
- Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety RisksFDA · safety information · accessed September 2026
- Compounding and the FDA: Questions and AnswersFDA · product quality and regulation
- AnaphylaxisMedlinePlus · recognizing an emergency
Educational information, not a recommendation to use a compound. Kairo does not give dosing advice. Review decisions with a licensed healthcare professional.