PANEL 04 / DOSE CONTEXT
TB-500 dosage, as it appears in the studies
The animal mg/kg ranges, the human intravenous Phase 1 cohorts, and the routes researchers used — described as study parameters, never as a human protocol.
TB-500 dosage in the research literature
TB-500 dosage in the research literature is almost entirely thymosin beta-4 dosage, and it spans a wide range. Animal studies dosed full-length Tβ4 from roughly 6-12 mg/kg in cardiac and neuro rodent models up to the 2-18 mg/kg intraperitoneal range used in the embolic-stroke dose-response study, where ~3.75 mg/kg was the modeled optimum [4]. A muscular-dystrophy study in mdx mice used 150 µg intraperitoneally twice weekly for six months [11]. At the other extreme, picogram-to-nanogram amounts are bioactive in vitro — about 10 pg stimulated keratinocyte migration in a wound assay [3].
In humans, a randomized placebo-controlled Phase 1 study dosed synthetic thymosin beta-4 intravenously at 42, 140, 420, or 1260 mg — a single dose, then daily for 14 days [6]. That is the full-length protein, not the 7-mer, and it was a safety and pharmacokinetic study, not an efficacy or dosing recommendation.
The TB-500 dosage in research is reported here as what was administered to which species at which dose by which route. None of it is a human-use protocol. Community "loading then maintenance" schedules circulated in athletic and peptide-research circles are not derived from controlled human trials and have no published clinical validation — and the non-monotonic stroke result, where 18 mg/kg lost the benefit seen at 12 mg/kg, is direct evidence that "more" is not a safe assumption [4].
Routes researchers used
Four routes appear in the record. Intraperitoneal injection predominates in rodent efficacy studies [4][3]. Intravenous administration was used in the human Phase 1 of full-length Tβ4 and in some cardiac models [6]. Topical and ophthalmic routes appear in corneal and dermal wound work and in dry-eye RCTs using the clinical-grade RGN-259 formulation [5]. Subcutaneous and intramuscular routes circulate as community research-use routes but do not come from controlled human efficacy trials.
TB-500 is supplied as a lyophilized powder, reconstituted in bacteriostatic or sterile water and kept refrigerated. As a short acetylated peptide it resists degradation better than the full protein, but is still subject to proteolysis and freeze-thaw loss [11].