About Legal TB-500.

What this site is

Legal TB-500 is a deadpan survey of the peer-reviewed research on TB-500 and its parent protein, thymosin beta-4, alongside the public regulatory record — a reading of what the studies measured, not a service built on it. No clinic, no clinicians, no medical advice; nothing here is made, sold, or shipped. The job is to report the findings plainly and cite each one to source.

The organizing idea is a single, stubborn distinction: TB-500 is a seven-residue synthetic fragment, while almost all of its efficacy literature is on the full-length 43-residue protein ^[5]. We treat that gap as the central fact, not a disclaimer buried at the bottom. Every quantitative claim on this site is tied to a numbered source on the references page, and where a study used the full protein rather than the fragment, we say so.

What 'Legal' in the name means

The word 'legal' in this site's name is editorial framing — it signals that the site reads the legal and regulatory record carefully, with the FDA 503A status and the WADA standing placed up front. It is not a claim that TB-500 is approved, and it is not legal advice. TB-500 is not an FDA-approved drug, and FDA placed it in 503A Category 2 in its September 29, 2023 update ^[18].

We describe the lawful compounding pathway in general terms and we cite the FDA pages that establish the current status. We do not name pharmacies, clinics, telehealth providers, or vendors; we do not provide dosing; and we do not describe ways to obtain any substance outside the lawful framework. The honest reading of the record — including its safety signal and its human-data gaps — is the entire point of the project.

How we handle the science

We lead with what was measured and attribute it afterward. We prefer a precise blank — 'there is no validated human pharmacokinetic half-life for the fragment' — to a vague reassurance ^[6]. We surface the misses as plainly as the hits: the non-monotonic stroke dose-response ^[4], the null muscle-strength result in mdx mice ^[5], and the porcine ischemia-reperfusion study where systemic Tβ4 did not help ^[5]. The tumor and angiogenesis safety signal is stated as a recognized concern wherever it is relevant ^[5]. The aim is a calm, checkable record — not a verdict, and not a sales pitch.