Collection episode 02 · 2:03 · English
Peptides in 2TM · Thymosin beta-4 & TB-500
Identify the molecule
Follow molecular identity into a defined corneal-healing study, then examine how preparation, population, and measured outcomes shape an evidence claim.
English narration with optional English captions. Caption timing is recognition-assisted. Translated subtitles are not yet available for this episode.
Published . Evidence checked: October 15, 2026.
Behind the film: references & context
Molecular identity comes first
Full-length thymosin beta-4 contains 43 amino acids and participates in actin regulation. Esposito and colleagues identified an acetylated seven-residue fragment in material sold as TB-500. FDA’s evaluation describes inconsistent common-name use. Evidence must stay attached to the identified substance and preparation. [1][2]
The defined eye-formulation study
A randomized study of RGN-259 for neurotrophic keratopathy enrolled 18 participants. Complete healing at four weeks occurred in 6 of 10 treated participants and 1 of 8 receiving placebo. The primary comparison had p=0.0656 against a planned 0.05 threshold. Later follow-up favored treatment. Missing the primary threshold does not prove there was no benefit. [3]
Study limitations and interpretation
The study stopped early because of slow recruitment and included developer-affiliated authors. Its small sample and primary-endpoint uncertainty limit the strength of inference. Later outcomes must remain distinguishable from the primary comparison. [3]
Applying the findings to a different claim
An eye formulation tested in a particular corneal disease does not establish the benefits or safety of a different fragment for muscle or tendon recovery. Match the molecule, formulation, population, and endpoint before transferring a claim. [2][3]
Original sources and source access
- Esposito et al. (2012) — Analytical identification of TB-500
Primary analytical study. PMID 22962027; DOI 10.1002/dta.1402. Characterization is distinct from clinical-benefit evidence.
- FDA (2026) — Evaluation of TB-500-related bulk drug substances
Official evaluation describing molecular identity, common naming, and evidence limitations. A compounding evaluation is distinct from approval of a finished medicine.
- Sosne et al. (2023) — RGN-259 randomized neurotrophic-keratopathy study
Primary publication. DOI 10.3390/ijms24010554; PMID 36613994. Small randomized eye-formulation study; primary and later outcomes are distinguished.
Production notes
Ten original AI-generated images each appear once, with the established series artwork at the opening and closing. One synthetic narrator speaks at normal synthesis speed. The chart uses the study’s published counts. Prompts, timing, captions, narration, and rendering files are included in the source package.
Read the English transcript
Thymosin beta-4 and TB-500 are often mentioned together. Before following a healing claim, identify the molecule.
Full-length thymosin beta-4 contains 43 amino acids. It helps regulate actin, a protein involved in cell shape and movement. That biology explains research interest; it does not make every related preparation equivalent.
A 2012 analytical study identified an acetylated seven-amino-acid fragment in material sold as TB-500. The FDA also warns that this common name has been used for different substances. A label alone cannot settle identity.
Human research has tested a defined thymosin beta-4 eye formulation for neurotrophic keratopathy, a disease in which the corneal surface struggles to heal.
In one randomized study, six of ten treated participants had complete healing at four weeks, compared with one of eight receiving placebo. The primary comparison had a P value of 0.0656, above the study's 0.05 threshold.
Later follow-up favored treatment, but the small study still calls for careful interpretation. Missing that threshold does not prove there was no benefit.
An eye formulation studied in a particular disease does not establish the benefits or safety of a different fragment used for muscle or tendon recovery.
The practical research habit is simple: match the molecule, formulation, population, and endpoint. Keep promising biology connected to the preparation actually tested.
World Peptide Foundation. Peptides in 2. Every experience matters.
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