# Thymosin Alpha-1 Dosage: The Doses Studied in Trials, by Population and Route > Thymosin Alpha-1 dosage as it appeared in research: the 0.8-6.4 mg single-dose range, the 1.6 mg twice-weekly regimen, sepsis and COVID-19 protocols, half-life and route — reported, not prescribed. The doses that appeared in the published record, attributed to the population and route they were studied in — reference data, not instructions. ## Read this first Everything below is **research data, not a prescription**. The numbers describe what investigators gave to specific groups of patients, in specific settings, by injection under the skin — they are not a recommendation for anyone, and this site gives no human dosing instructions. **Thymosin Alpha-1** has been studied as a subcutaneous injection in essentially every clinical trial. The figure cited most often is 1.6 mg twice a week, the regimen used abroad for chronic hepatitis. Across the wider literature, single doses studied span a range, and sepsis trials used a more frequent schedule for about a week. It clears the bloodstream quickly — its half-life is short — which shapes how trials spaced the injections. If you take one thing from this page, let it be the gap between 'a dose used in a monitored trial' and 'a dose anyone should self-administer.' The studies do not support the second. ## Thymosin alpha 1 dosage: the studied ranges A comprehensive review reports the standard single subcutaneous dose of Tα1 ranges from 0.8 to 6.4 mg, with multiple-dose regimens of 1.6-16 mg over five to seven days [4]. The most widely cited chronic regimen is **1.6 mg subcutaneously twice weekly**, the thymalfasin-equivalent schedule used internationally for chronic hepatitis B and C [4]. In chronic hepatitis B specifically, one study administered 1.2 mg for 24 weeks [8]. These are the figures as they appear in the literature — by population and route — and nothing here should be read as a target for personal use. ## Thymosin alpha 1 injection: routes and schedules in trials Tα1 is given by subcutaneous injection in clinical research; mechanistic work also uses in-vitro, ex-vivo and murine intraperitoneal routes, but the human route of record is subcutaneous [5][9]. Trial schedules tracked the indication. The sepsis protocols (ETASS, TESTS) used 1.6 mg every 12 hours for five to seven days [2][3]. COVID-19 cohort work used 1.6 mg daily [6]. Cancer-adjuvant protocols used 1.6 mg twice weekly within combination regimens [7]. The peptide is supplied lyophilized (freeze-dried) and reconstituted before injection; it is highly acidic, does not bind plasma proteins extensively, and is broken down by tissue and circulating aminopeptidases [4]. ## How the studied schedules differ by setting Reading the doses side by side makes the pattern clear, and underlines that no single figure is 'the' dose. The chronic, slow-burn indications used infrequent injections over a long horizon: chronic hepatitis B and C are the classic 1.6 mg twice-weekly setting, and one hepatitis B study ran 1.2 mg for 24 weeks [4][8]. The acute, high-stakes settings used frequent injections over a short window: the sepsis trials gave 1.6 mg every 12 hours for five to seven days [2][3], and a severe acute pancreatitis pilot used 3.2 mg twice daily for seven days. COVID-19 cohorts sat in between, at 1.6 mg once daily [6]; a lung-cancer chemoradiotherapy-adjunct study extended weekly injection for up to twelve months. The schedule, in other words, was tuned to whether the goal was sustained immune support or rapid immune rescue — and every one of these was a supervised trial, not a template for self-use [4]. ## Half-life and pharmacology After subcutaneous injection in healthy volunteers, Tα1 shows an elimination half-life of roughly 2 hours, with peak plasma levels within about 1-2 hours and a return toward baseline within roughly 24 hours; its volume of distribution is consistent with distribution into extracellular fluid [4]. N-terminal acetylation of the peptide is required for its biological activity. Because the molecule clears quickly, the durable effects studied in trials are attributed to the immune signaling it sets off — dendritic-cell and T-cell changes that outlast the peptide's brief presence in the blood — rather than to sustained circulating levels [5]. This is part of why trials dosed it repeatedly rather than once: the lasting outcome they tracked came from the immune cascade, not from keeping a steady drug level in the blood. ## Handling, stability and why figures vary The peptide is highly acidic, with an isoelectric point around 4.2; it does not bind plasma proteins to any great extent and is broken down by tissue and circulating aminopeptidases [4]. It is supplied lyophilized — freeze-dried to a stable powder — and reconstituted before use, which is one reason research-use communities report uncertainty about correct mixing and sterile handling. The wide span in reported figures (0.8 to 6.4 mg for a single dose) reflects the breadth of indications and protocols studied over four decades rather than a single settled regimen [4]. The dose that recurs most across the chronic-disease literature is the 1.6 mg twice-weekly schedule, but even that is the *studied* regimen abroad, not guidance for anyone. ## Why this is research context, not a protocol Thymosin Alpha-1 has no FDA-approved labeling in the United States, so there is no US-sanctioned dose, titration schedule, or course of treatment to report [4]. Every figure on this page comes from a clinical trial or a review of trials, where the peptide was given to a defined patient population under medical supervision and monitored for a measured endpoint. Material obtained as research-grade peptide sits outside that regulated chain entirely, with no guarantee of purity, content or identity [4]. The gap between a dose used in a supervised trial and a dose anyone administers to themselves is the whole point of reading dosing data this way — the studies describe the former and say nothing in support of the latter. --- A register of record on the thymic immune peptide thymosin alpha-1 — every claim logged to its study, the largest sepsis trial's null result kept in plain view, and not one thing here a clinic, a prescription, or for sale.