Dosage · research context only
TB-500 Dosage as It Appears in the Research Record
Doses studied in animals and in the human IV thymosin beta-4 trial — described as administered to a species, never as a human protocol.
How TB-500 dosage appears in the literature
TB-500 dosage in this binder is research context, not guidance. No dose here is a recommendation, and nothing on this page tells anyone what to take. The figures below are what specific studies administered to specific species by specific routes, and almost all of them used full-length thymosin beta-4 rather than the TB-500 heptapeptide [6].
Animal studies dose the parent protein across a wide range: roughly 6–12 mg/kg in cardiac and neurological rodent models; 2–18 mg/kg intraperitoneally in the embolic-stroke dose-response study (optimal modeled near 3.75 mg/kg) [4]; and 150 µg twice weekly intraperitoneally for six months in the mdx muscular-dystrophy study [5]. The human Phase 1 study dosed synthetic thymosin beta-4 intravenously at 42, 140, 420 and 1260 mg — single dose then daily for 14 days [6]. Picogram-to-nanogram amounts are bioactive in vitro: about 10 pg was active in keratinocyte-migration assays, and nanomolar thymosin beta-4 stimulated hair-follicle stem cells [3][5]. The TB-500 dosage in the literature is reported, never prescribed.
TB-500 Half-Life: What the Pharmacokinetic Record Shows
No validated human pharmacokinetic half-life exists for the TB-500 heptapeptide [6]. The relevant human pharmacokinetic data come from the intravenous full-length thymosin beta-4 Phase 1 study, where pharmacokinetics were dose-proportional and the half-life increased with dose across the 42–1260 mg cohorts [6]. Anti-doping LC-MS work characterizes TB-500 and its metabolites in equine plasma and urine for detection purposes, not for human pharmacokinetics [6][17]. In short, the TB-500 half-life most often quoted online is not a measured human value for the 7-mer.
Can TB-500 Be Taken Orally?
The studied routes do not include validated oral dosing of the fragment. The predominant route in rodent efficacy studies is intraperitoneal; intravenous was used in the human Phase 1 of full-length thymosin beta-4 and in some cardiac models; topical and ophthalmic routes appear in the corneal and dermal wound and dry-eye work (RGN-259, full-length thymosin beta-4); and subcutaneous or intramuscular routes appear in community research use but not in controlled human efficacy trials [6]. As a peptide, oral bioavailability faces gastrointestinal proteolysis, and no controlled human oral data for TB-500 exist [6]. The question of whether TB-500 is taken orally cannot be answered with a validated human route from the published record.
Form, stability, and why product quality is a caveat
Research-grade TB-500 is supplied as a lyophilized (freeze-dried) powder, typically reconstituted in bacteriostatic or sterile water and kept refrigerated [6]. As a short acetylated peptide it is more chemically robust than the full-length protein, but it is still subject to proteolysis and freeze-thaw degradation [6]. Identity and purity of unregulated material is a recurring concern — correct sequence (full-length versus fragment) is not guaranteed — which complicates interpreting any anecdotal result [6]. Community "loading then maintenance" protocols are not derived from controlled human trials and have no published clinical validation; the non-monotonic stroke dose-response (no benefit at the highest 18 mg/kg dose) directly argues against "more is better" loading logic [4].